PULSE CRANKCASE DRIVEN FUEL PUMP FUEL SYSTEM Section 3A Pulse Crnkcse Driven Fuel Pump Tle of Contents Specifictions........................... 3A-1 Specil Tools........................... 3A-1 Fuel Pump............................. 3A-2 Fuel Pump Description/Opertion......... 3A-3 Checking for Restricted Fuel Flow Cused y Anti-Siphon Vlves.................... 3A-3 Specifictions Checking Fuel Pump Lift (Vcuum)........ 3A-4 Vcuum Test Trouleshooting.......... 3A-4 Testing Fuel Pump.................... 3A-5 Fuel Pump Removl/Disssemly......... 3A-6 Clening/Inspection................... 3A-7 Ressemly/lnstlltion............... 3A-7 3 A FUEL SYSTEM Fuel Pressure Crnkcse Pump @ Idle @ WOT Model 75/90/115 Norml 13.7-20.5 kp (2-3 psi) Minimum 6.8 kp (1 psi) Norml 41.0-54.8 kp (8-10 psi) Mximum 68.5 kp (10 psi) Minimum 4 psi (27.4 kp) Specil Tools NOTE: Electric fuel pump pressure, if used in conjunction with engine mechnicl fuel pump, must e limited to no more thn 27.4 kp (4 psi). Fuel Pressure/Vcuum Guge 0 103.4 kp (0-15 psi) Otin Loclly o57721 90-889785 APRIL 2003 Pge 3A-1
PULSE CRANKCASE DRIVEN FUEL PUMP Fuel Pump TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 1 FUEL PUMP ASSEMBLY 1 1 FUEL PUMP 2 1 DIAPHRAGM KIT 3 2 GASKET BOOST 4 2 DIAPHRAGM 5 1 GASKET PULSE 6 1 SPRING 7 1 CAP 8 1 RETAINER 9 1 SPRING 10 1 CAP 11 1 BASE 12 1 PLATE 13 1 ELBOW (45 DEGREE) 14 1 ELBOW (90 DEGREE) 15 2 SCREW FUEL PUMP (M5 x 40) 60 6.8 16 2 SCREW PUMP TO CRANKCASE (M6 x 50) 60 6.8 17 1 ELBOW 18 3 O RING (WB#326 028) 19 1 GASKET Pge 3A-2 90-889785 APRIL 2003
Fuel Pump Description/Opertion PULSE CRANKCASE DRIVEN FUEL PUMP The fuel pump is crnkcse-pressure-operted, diphrgm type pump. Crnkcse pulsting pressure (creted y the up nd down movement of piston) is trnsferred to fuel pump y wy of pssge (hole) etween crnkcse nd fuel pump. When piston is in n upwrd motion, vcuum is creted in the crnkcse, thus pulling in on the fuel pump diphrgm. The inlet check vlve (in fuel pump) is opened nd fuel (from fuel tnk) is drwn into fuel pump. Downwrd motion of the piston forces the mixture out of the crnkcse into the cylinder. This motion lso forces out on the fuel pump diphrgm, which, in turn, closes the inlet check vlve (to keep fuel from returning to fuel tnk) nd opens the outlet check vlve, thus forcing fuel to the VST. Checking for Restricted Fuel Flow Cused y Anti-Siphon Vlves While nti-siphon vlves my e helpful from sfety stnd-point, they clog with deris, they my e too smll, or they my hve too hevy spring. Summrizing, the pressure drop cross these vlves cn, nd often does, crete opertionl prolems nd/or power hed dmge y restricting fuel to the fuel pump nd VST. Some symptoms of restricted (len) fuel flow, which could e cused y use of n nti-siphon vlve, re: 1 - Loss of fuel pump pressure 2 - Loss of power 3 - High speed surging 4 - Preignition/detontion (piston dome erosion) 5 - Outord cuts out or hesittes upon ccelertion 6 - Outord runs rough 7 - Outord quits nd cnnot e restrted 8 - Outord will not strt 9 - Vpor lock Since ny type of nti-siphon device must e locted etween the outord fuel inlet nd fuel tnk outlet, simple method of checking [if such device (or d fuel) is prolem source] is to operte the outord with seprte fuel supply which is known to e good, such s remote fuel tnk. If, fter using seprte fuel supply, it is found tht the nti-siphon vlve is the cuse of the prolem, there re 2 solutions to the prolem; either 1) replce the nti-siphon vlve with one tht hs lighter spring tension or 2) replce it with solenoid-operted fuel shut off vlve. 90-889785 APRIL 2003 Pge 3A-3
PULSE CRANKCASE DRIVEN FUEL PUMP Checking Fuel Pump Lift (Vcuum) The squre fuel pump is designed to lift fuel (verticlly) out 1524 mm (60 in.) if there re no other restrictions in the system using fuel hose tht is 7.9 mm (5/16 in.) minimum dimeter. As restrictions re dded, such s filters, fittings, vlves etc., the mount of fuel pump lift decreses. Fuel pump vcuum nd ir ules in the fuel supply cn e checked with vcuum guge, t-fitting nd cler piece of fuel hose. Connect the cler hose etween the inlet fitting on the pulse driven fuel pump nd the vcuum guge t-fitting. Keep the t-fitting nd the guge s close s possile to the pump for the most ccurte redings. Connect the fuel line from the fuel tnk to the remining connection on the t-fitting. c -Cler hose -T-fitting c -Vcuum guge o57771 Vcuum Test Trouleshooting This test is normlly performed t n idle speed. As engine rpm increses, there will e slight increse in vcuum. The increse should not exceed specifiction Norml Reding Below 2.5 in. of mercury Reding ove 2.5 in. of mercury Restriction within the fuel system Restricted nti-siphon vlve Restriction within the primer ul Kinked or collpsed fuel hose Plugged wter seprting fuel filter (in the ot) Restriction in fuel line thru-hull fitting Restriction in fuel tnk switching vlves Plugged fuel tnk pick-up screen Pge 3A-4 90-889785 APRIL 2003
Testing Fuel Pump PULSE CRANKCASE DRIVEN FUEL PUMP Instll cler fuel hose etween fuel pump nd VST. Run engine, nd inspect fuel pssing thru hose for ir ules. Prolem: Air Bules in Fuel Line Low fuel in tnk. Fill tnk with fuel. Loose fuel line connection. Check nd tighten ll connectors. Fuel pump fitting loose. Tighten fitting. A hole or cut in fuel line. Check condition of ll fuel lines nd replce. Fuel pump nchor screw loose. Tighten ll screws evenly nd securely. Fuel pump filter cover nchor screw loose. Tighten screws securely. Fuel pump filter gsket worn out. Replce gsket. Fuel pump gsket worn out. Reuild fuel pump. Fuel vporizing Fuel with high reed vpor pressure (winter grde fuel) my vporize (form ules) when used in hot/wrm wether. Use fuel with lower reed vpor pressure (summer grde fuel). Prolem: Lck of Fuel Pump Pressure An nti-siphon vlve. See Checking for Restricted Fuel Flow preceding. Air in fuel line. See Air Bules in Fuel Line, ove. A dirty or clogged fuel filter. The fuel pickup in fuel tnk is clogged or dirty. Worn out fuel pump diphrgm. Worn out check vlve in fuel pump. A leky check vlve gsket. Pulse hole plugged. Hole in pulse hose. Loose pulse hose. Fuel hose internl dimeter too smll. Primer ul check vlve not opening. Clen or replce fuel filter. Clen or replce pickup. Reuild fuel pump. Reuild fuel pump. Reuild fuel pump. Remove fuel pump nd clen out holes. Replce pulse hose. Tighten connection. Use 5/16 I.D. fuel hose. Replce primer ul. Excessive fuel lift required. Fuel lift exceeds 2.5 in. of vcuum (mercury). 90-889785 APRIL 2003 Pge 3A-5
PULSE CRANKCASE DRIVEN FUEL PUMP Fuel Pump Removl/Disssemly IMPORTANT: Fuel pump diphrgm nd gskets should not e re-used once fuel pump is disssemled. 1. Disconnect fuel hose from tnk to fuel pump. 2. Disconnect pulse hose. 3. Remove 2 mounting screws. 4. Remove fuel pump. c d -Fuel hose -Pulse hoses o00884 c -Mounting screws d-fuel pump 5. Disssemle fuel pump. Pge 3A-6 90-889785 APRIL 2003
Clening/Inspection PULSE CRANKCASE DRIVEN FUEL PUMP 1. Clen fuel pump housing, check vlves, pulse chmer nd pump se in solvent nd dry ll ut check vlves with compressed ir. 2. Inspect ech check vlve for splits, chips nd for proper seling ginst pump housing. 3. Inspect oost springs for wekness or rekge. 4. Inspect fuel pump housing, pulse chmer nd se for crcks or rough gsket surfce nd replce if ny re found. 5. Inspect fitting on fuel pump housing for loosening or ny signs of fuel or ir leks. Replce or tighten fitting if lek is found. Ressemly/lnstlltion ASSEMBLY NOTE: The new repir kits contin check vlves mde of plstic mteril, impervious to dmge from dditives. When repiring the fuel pump discrd old ruer nd smll plstic check vlve disks, nd instll one new plstic disk under ech retiner. Cution must e tken not to push the check vlve retiner to tightly ginst the check vlve, this my cuse vlve to deform. CORRECT -Check vlve retiner -Check vlve (plstic) 1. Insert retiner through plstic check vlve. INCORRECT o57861 -Retiner -Plstic check vlve o23601 90-889785 APRIL 2003 Pge 3A-7
PULSE CRANKCASE DRIVEN FUEL PUMP 2. Instll check vlves nd retiners into fuel pump ody. 3. With retiner instlled in pump ody, rek retiner rod from retiner y ending sidewys. -Rod -Retiner cp o23601 4. Reinstll rod into retiner cp nd, use smll hmmer nd punch to tp rod down into retiner until flush with top of retiner. -Rod -Retiner cp o23601 Pge 3A-8 90-889785 APRIL 2003
PULSE CRANKCASE DRIVEN FUEL PUMP 5. Plce oost spring into pump ody nd plce cp onto oost spring. c -Boost spring -Pump ody c -Cp o50161 6. Assemle reminder of components s shown nd instll retining screws through to lign. 90-889785 APRIL 2003 Pge 3A-9
PULSE CRANKCASE DRIVEN FUEL PUMP 7. Instll pump onto engine. Torque ttching screws to specifiction. 8. Instll hoses onto proper fittings nd secure with cle ties. 9. Run engine nd check for leks. c d -Fuel hose -Pulse hoses o00884 c -Mounting screws d-fuel pump TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 2 SCREWS 60 6.8 Pge 3A-10 90-889785 APRIL 2003
FUEL SYSTEM Section 3B Direct Fuel Injection Tle of Contents DIRECT FUEL INJECTION Specifictions........................... 3B-2 Specil Tools........................... 3B-3 Throttle Body........................... 3B-6 Reed Block............................. 3B-8 Fuel System............................ 3B-10 Vpor Seprtor Components............. 3B-12 Fuel Ril Components................... 3B-14 Vpor Seprtor/Fuel Ril Mounting....... 3B-16 Air Hoses.............................. 3B-18 Air Compressor Components............. 3B-20 DFI Opertion.......................... 3B-22 Air Induction Through Crnkcse....... 3B-22 Air Compressor System............... 3B-22 Fuel................................ 3B-22 Oil.................................. 3B-23 Electricl............................ 3B-23 Opertion........................... 3B-23 Testing Electric Fuel Pump Pressure Output 3B-24 Low Pressure Electric Fuel Pump....... 3B-24 High Pressure Electric Fuel Pump...... 3B-25 Fuel Mngement Assemly Removl..... 3B-26 Air Temperture Sensor Removl...... 3B-31 Air Temperture Sensor Instlltion..... 3B-31 MAP Sensor Removl................ 3B-32 MAP Sensor Instlltion............... 3B-32 Throttle Plte Assemly Removl....... 3B-33 Throttle Plte Assemly Instlltion..... 3B-33 Reed Block Assemly Removl........ 3B-34 Reed Block Assemly Instlltion....... 3B-34 Vpor Seprtor Tnk Disssemly..... 3B-37 Fuel Flow Director Components........ 3B-40 Vpor Seprtor Tnk Ressemly..... 3B-41 Air Plenum Instlltion................ 3B-46 Vpor Seprtor Instlltion........... 3B-46 Fuel Ril Removl.................... 3B-48 Fuel Pressure Regultor.............. 3B-54 Air Pressure Regultor................ 3B-59 Air Regultor Trouleshooting.......... 3B-60 Fuel Ril Clening.................... 3B-64 Direct Injector Removl............... 3B-64 Direct Injector Lek Test............... 3B-67 Fuel Ril nd Direct Injector Instlltion. 3B-68 Air Compressor...................... 3B-69 Notes:................................. 3B-73 Air Compressor Disssemly/Ressemly 3B-74 Air Compressor End Cp/Crnkshft Removl nd Ressemly............. 3B-76 Air Compressor Flow Digrm......... 3B-81 Air Compressor Pressure Test......... 3B-82 Fuel Injector Test..................... 3B-84 3 B 90-889785 APRIL 2003 Pge 3B-1
Specifictions Fuel Pressure Air Pressure Fuel/Air Differentil High nd Low Pressure Fuel Pump Amperge Drw Low Pressure Electric Fuel Pump Output Fuel System Specifictions 744.6 ± 13.8 kp (108 ± 2 psi) 648.1 ± 13.8 kp (94 ± 2 psi) 96.5 kp ± 6.9 kp (14.0 ± 1.0 psi) 10-14 Amps 137.9 kp - 206.8 kp (20-30 psi) Fuel Injector Ohm Resistnce 1.8 ± 0.1Ω Direct Injector Ohm Resistnce 1.3 ± 0.3Ω Air Compressor Specifictions Air Compressor Type Compressor Output Reciprocting Piston (1.14 to 1 rtio with engine RPM) @ Idle 655 kp (95 psi) Cylinder Block Displcement 60 cc (3.66 cu. in.) Cylinder Bore Dimeter (Stndrd) Tper/Out of Round/Wer Mximum Bore Type 52.0 mm (2.0472 in.) 0.025 mm (0.001 in.) Cst Iron Stroke Length 27.9 mm (1.100 in.) Piston Piston Type Aluminum Piston Dimeter 51.95 ± 0.010 mm (2.0453 ±.0004 in.) Dimension A t Right Angle (90 ) to Piston Pin 0.300 in. Piston Ring End Gp Top Ring Middle Ring Bottom Ring 0.15-0.30 mm (0.0059-0.0118 in.) 0.15-0.30 mm (0.0059-0.0118 in.) 0.10-0.35 mm (0.0039-0.014 in.) Reeds Reed Stnd Open 0.25 mm (0.010 in.) Pge 3B-2 90-889785 APRIL 2003
Specil Tools DIRECT FUEL INJECTION Duel Fuel/Air Pressure Guge 1103.2 kp (160 psi) 91-852087A1/A2/A3 Adptors to convert pressure guge 91-852087A1/A2 91-803804A2 to n A3 c d e NOTE: 2 Adptors 91-803804A2 re required to convert pressure guge set. -1/2 in. to 1/4 in. Adpter if required -Femle quick disconnect c -Mle quick disconnect d-screw on Schrder e -O-ring 25-803803 Sel/Teflon Ring Instlltion Tool 91-851980--3 56015 90-889785 APRIL 2003 Pge 3B-3
Sel/Teflon Ring Sizing Tool 91-851980-2 o56014 DMT 2000 Digitl Tchometer Multi-meter 91-854009T1 Direct Injector Removl Tool 91-883521 Pge 3B-4 90-889785 APRIL 2003
Clmp Tool Kit 91-803146A2 o57316 -Clmp tool 91-803146T Gercse Lekge Tester FT-8950 o57714 Regultor Instlltion Tool 91-889431 o59361 90-889785 APRIL 2003 Pge 3B-5
Throttle Body Pge 3B-6 90-889785 APRIL 2003
Throttle Body (Continued) DIRECT FUEL INJECTION TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 1 1 THROTTLE BODY ASSEMBLY 2 1 PLATE 3 4 SCREW 100 11.3 4 1 GROMMET 5 1 GROMMET 6 1 CLAMP 7 1 SCREW 8 1 WASHER 9 1 WASHER 10 1 BUSHING 11 1 THROTTLE LEVER KIT 12 1 THROTTLE ROLLER ASSEMBLY 13 1 LOCKWASHER 14 1 WASHER 15 1 WASHER 16 1 SCREW 17 1 ROLLER 18 1 BRACKET 19 3 SCREW (M6 x 16) 105 11.9 20 2 CABLE 21 1 CAM 22 1 SPACER 23 1 WASHER 24 1 SCREW (M6x 40) 95 10.7 25 1 COUPLER 26 1 TPI 27 3 SCREW 24 2.7 28 1 CLAMP Oetiker 29 2 CONDUIT [33 cm (13 in.)] 90-889785 APRIL 2003 Pge 3B-7
Reed Block 25 14 Tue Ref. # 14 Description 2 Cycle Premium Outord Oil Mercury Prt Numer Quicksilver Prt Numer 92-802813A1 92-802813Q1 25 Liquid Neoprene 92-25711-3 92-25711-3 Pge 3B-8 90-889785 APRIL 2003
Reed Block (Continued) DIRECT FUEL INJECTION TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 1 1 SHIFT RAIL 2 2 TAB WASHER 3 2 SCREW (M8 x 25) 18 24.4 4 1 SLIDE 5 1 NUT 6 1 WASHER 7 1 NUT Drive tight; ut joint must e free to pivot 8 1 GASKET 9 1 LOWER END CAP ASSEMBLY 10 1 CHECK VALVE 11 1 OIL SEAL 12 1 O-RING 13 3 SCREW (M10 x 25) 14 1 REED ADAPTOR PLATE 15 1 GASKET 16 1 FITTING 17 1 COVER 18 1 GASKET 19 9 SCREW (M8 x 45) 18 24.4 20 15 SCREW (M8 x 35) 18 24.4 21 3 REED BLOCK 22 3 GASKET 23 6 SCREW (M6 x 20) 90 10.2 24 1 MAP SENSOR 25 1 BRACKET 26 1 SCREW (M6 x 16) 90 10.2 27 1 TEMPERATURE SENSOR 13 1.4 28 1 O-RING 29 1 NEGATIVE BATTERY CABLE 30 2 SCREW (M8 x 14) 18 24.4 31 4 WASHER 32 1 CLAMP 90-889785 APRIL 2003 Pge 3B-9
Fuel System NOTE: A = To Crnkcse NOTE: B = To Vent Fitting Pge 3B-10 90-889785 APRIL 2003
Fuel System (Continued) DIRECT FUEL INJECTION TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 1 1 HOSE VENT 2 AR CABLE TIE (8 in.) 3 1 HOSE ASSEMBLY 4 1 HOSE ASSEMBLY 5 1 SCHRADER VALVE 6 1 O RING 7 1 CLIP 8 1 SCREW (M6 x 12) 90 10.2 9 1 TUBING (10-1/2 in.) 10 1 FITTING 11 1 TUBING (28 in.) 12 1 TUBING (4-1/2 in.) 13 1 CLAMP (15.3) 14 1 HOSE 15 1 SEAL 90-889785 APRIL 2003 Pge 3B-11
Vpor Seprtor Components A Pge 3B-12 90-889785 APRIL 2003
Vpor Seprtor Components (Continued) DIRECT FUEL INJECTION TORQUE REF. NO. QTY. DESCRIPTION l. in. l. ft. N m 1 1 COVER KIT 2 1 SEAT 3 1 BAFFLE PLATE 4 2 SCREW 22 2.5 5 1 GASKET 6 1 FITTING 75 8.5 7 1 O-RING 8 1 FITTING 50 5.5 9 1 PLUG 45 5 10 1 FUEL FILTER 11 1 FLOAT KIT 12 1 FLOAT PIN 13 1 FUEL PUMP HIGH PRESSURE 14 1 SLEEVE 15 1 O-RING 16 1 SEAL 17 1 RETAINER 18 11 SCREW 40 4.5 19 1 BOOST PUMP 20 1 GROMMET 21 1 O-RING 22 1 SEAL 23 1 BOWL KIT 24 1 WIRE 25 1 CHECK VALVE 26 2 FITTING 27 1 INLET VALVE KIT 28 2 DRAIN SCREW 15 1.7 29 2 O-RING 30 1 WATER SENSOR 31 1 ELBOW (90 DEGREE) Note 32 2 O-RING 33 1 INSERT NOTE: Instll elow fitting in to VST 5 turns minimum 7 turns mximum. A Torque retiner screws to 2.5 Nm (22 l. in.) 90-889785 APRIL 2003 Pge 3B-13
Fuel Ril Components Pge 3B-14 90-889785 APRIL 2003
Fuel Ril Components (Continued) DIRECT FUEL INJECTION TORQUE REF. NO. QTY. DESCRIPTION l. in. l. ft. N m 1 1 FUEL RAIL ASSEMBLY 2 1 FUEL PLUG 3 2 SEAL 4 2 CLAMP 5 9 SCREW (M5 x 10) 70 8 6 1 O-RING 7 1 FITTING 8 1 BRACKET 9 3 INJECTOR 10 1 O-RING KIT 11 1 O-RING KIT 12 3 RETAINER 13 2 VALVE KIT - SCHRADER 14 2 CAP 15 1 O-RING KIT 16 2 CLAMP 17 1 ELBOW 18 1 AIR PLUG 19 1 FITTING 20 1 O-RING 21 2 CLAMP 22 1 O-RING KIT 23 1 O-RING (16 per kit) 90-889785 APRIL 2003 Pge 3B-15
Vpor Seprtor/Fuel Ril Mounting Tue Ref. # 110 Description 4 Stroke 10W30 Outord Oil Mercury Prt Numer Quicksilver Prt Numer 92-802833A1 92-802833Q1 Pge 3B-16 90-889785 APRIL 2003
Vpor Seprtor/Fuel Ril Mounting (Continued) DIRECT FUEL INJECTION TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm 1 2 STUD (M10 x 91) Drive Tight 2 2 NUT 33 44.7 3 3 AIR INJECTOR 4 3 CUPPED WASHER 5 2 SPACER 6 3 GROMMET 7 3 WASHER 8 2 SCREW (M8 x 60) 18 24.4 9 1 SCREW (M8 x 35) 18 24.4 10 1 BUSHING 90-889785 APRIL 2003 Pge 3B-17
Air Hoses Pge 3B-18 90-889785 APRIL 2003
Air Hoses (Continued) DIRECT FUEL INJECTION TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm 1 1 TUBING [20.3 cm (8 in.)] 2 2 CLAMP (15.3) 3 1 HOSE 4 1 HOSE ASSEMBLY 5 2 CABLE TIE [20.3 cm (8 in.)] 6 1 AIR MUFFLER 7 1 HOSE [11.4 cm (4-1/2 in.)] 90-889785 APRIL 2003 Pge 3B-19
Air Compressor Components 7 7 14 14 14 14 9 9 9 Tue Ref. # Description Mercury Prt Numer Quicksilver Prt Numer 7 9 14 Loctite 271 Thredlocker Loctite 567 PST Pipe Selnt 2 Cycle Premium Outord Oil 92-809819 92-809819 92-809822 92-809822 92-802813A1 92-802813Q1 Pge 3B-20 90-889785 APRIL 2003
Air Compressor Components (Continued) DIRECT FUEL INJECTION TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 1 1 AIR COMPRESSOR 2 1 END CAP 3 1 O RING 4 1 CONNECTING ROD 5 1 PISTON ASSEMBLY (WITH RINGS) 6 2 LOCK RING 7 1 REED PLATE ASSEMBLY 8 1 GASKET 9 1 GASKET 10 1 COMPRESSOR HEAD 11 1 ELBOW (45 Degree) 12 4 SCREW (M8 x 1.25) 20 27.1 13 2 ELBOW 14 1 FITTING 25 33.9 15 1 O RING 16 1 TEMPERATURE SENSOR 13 1.4 17 1 O RING 18 3 CHECK VALVE 58 6.6 19 1 PIN 45 5.1 20 1 ELBOW 21 5 CABLE TIE 22 1 HOSE 23 1 CHECK VALVE 24 1 SCREW (M6 x 20) 100 11.3 25 1 PULLEY 26 3 SCREW (M6 x 12) 100 11.3 27 1 TENSIONER ARM 28 1 PULLEY 29 1 SCREW (M10 x 25) 18.8 25.4 30 1 BEARING 31 1 BUSHING 32 2 TUBING [45.7 cm (18 in.)] 33 1 SPRING 34 1 SCREW (M10 x 45) 16.7 22.6 35 1 WASHER 36 1 TUBING [55.8 cm (22 in.)] 37 6 CABLE TIE [20.3 cm (8 in.)] 38 3 SCREW (M8 x 90) 18 24.4 90-889785 APRIL 2003 Pge 3B-21
DFI Opertion Air Induction Through Crnkcse Air Compressor System Comustion ir enters the cowl through holes locted in the top ft end of the cowl. The cowl liner directs this ir to the ottom of the powerhed. This limits the exposure of slt ir to the components inside the engine cowl. Once inside the cowl the ir enters the plenum through the throttle shutter which is locted in the plenum ssemly. The ir then continues through the reed vlves nd into the crnkcse. The throttle shutter is ctuted y the throttle shft. Mounted on seprte shft is throttle position sensor (TPS). This sensor tells the propulsion control unit (PCM) the position of the throttle. Fuel Air from inside the engine cowl is drwn into the compressor through n ir filter in the ir ttenutor. This ttenutor cts like muffler to quiet compressor noise nd contins filter to prevent the ingestion of deris into the compressor. The compressor is driven y elt from pulley mounted on the flywheel nd is utomticlly self-djusted using single idler pulley. This ir compressor is single cylinder unit contining connecting rod, piston, rings, erings, reed vlves, nd crnkshft. The compressor is wter cooled to lower the temperture of the ir chrge nd is luricted y oil from the engine oil pump ssemly. As the compressor piston moves downwrd inside the cylinder, ir is pulled through the filter, reed vlves nd into the cylinder. After the compressor piston chnges direction, the intke reeds close nd the exhust reeds open llowing compressed ir into the hose leding to the ir/fuel rils. The ir/fuel rils contin two pssges; one for fuel, the second for ir. The ir pssge is common etween ll the cylinders included in the ril. A hose connects the ril ir pssge to the ir compressor. An ir pressure regultor will limit the mount of pressure developed inside the ir pssges to pproximtely 96.5 kp (14 psi) elow the pressure of the fuel inside the fuel pssges [i.e. 648.1 kp (94 psi) ir vs 744.6 kp (108 psi) fuel]. Air exiting the pressure regultor is dischrged through muffler into the lower cowling. Fuel for the engine is stored in typicl fuel tnk. A primer ul is instlled into the fuel line to llow priming of the fuel system. A vpor seprtor mounted diphrgm fuel pump drws fuel through the fuel line, primer ul nd fuel pump ssemly. The pump then pushes the fuel through wter seprting fuel filter. This filter removes ny contmintes nd wter efore the fuel reches the vpor seprtor. Fuel vpors re vented through the ottom cowling into the tmosphere. The electric fuel pump is cple of developing fuel pressures in excess of 744.6 kp (108 psi). Fuel inside the ril must remin pressurized t exctly 96.5 kp (14 psi) over the ir ril pressure or the PCM (mp) clirtions will e incorrect. Fuel from the vpor seprtor is supplied to the top of the fuel ril. Fuel is stored inside the ril until n injector opens. A fuel pressure regultor controls pressure in the fuel ril, nd llows excess fuel to return into the vpor seprtor. The fuel regultor not only regultes fuel pressure ut lso regultes it t 96.5 kp (14 psi) higher thn whtever the ir ril pressure is. The fuel regultor diphrgm is held closed with spring tht requires 96.5 kp (14 psi) to force the diphrgm off the diphrgm set. The ck side of the diphrgm is exposed to ir ril pressure. As the ir ril pressure increses, the fuel pressure needed to open the regultor will eqully increse. Exmple: If there is 344.7 kp (50 psi) of ir pressure on the ir ril side of the diphrgm, 441.3 kp (64 psi) of fuel pressure will e required to open the regultor. The fuel ril is wter cooled. Pge 3B-22 90-889785 APRIL 2003
Oil Electricl Opertion DIRECT FUEL INJECTION Oil in this engine is not mixed with the fuel efore entering the comustion chmer. Oil is stored inside n engine mounted reservoir. A remote oil tnk is ville s n option. Crnkcse pressure will force oil from the remote oil tnk into the oil reservoir on the front of the powerhed. Oil will flow from the oil reservoir into the oil pump. The oil pump is solenoid design. It is ctivted y the PCM nd includes 7 pistons with corresponding dischrge ports. The oil pump is mounted on the electricl plte. Ech cylinder is luricted y one of the dischrge ports. The oil is dischrged into the crnkcse. The seventh pssge connects to the hose tht leds to the ir compressor for luriction. Excess oil from the compressor returns into the cylinder ores. The PCM will chnge the dischrge rte of the oil pump, depending upon engine demnd. The PCM will lso pulse the pump on initil strt up to fill the oil pssges eliminting the need to leed the oil system. The PCM provides dditionl oil for rek-in, s determined y its internl clock. The oil rtio vries with engine RPM nd lod. The electricl system consists of the PCM, crnk position sensor (flywheel speed & crnkshft position), throttle position sensor (TPS), MAP sensor, engine temperture sensor, ignition coils nd injectors (fuel & direct). The engine requires ttery to strt (i.e. the ignition nd injection will not occur if the ttery is ded). The system will run off of the lterntor. The opertion of the system hppens in milliseconds (ms). Exct timing is criticl for engine performnce. As the crnkshft rottes, ir is drwn into the crnkcse through the throttle shutter, into the plenum nd through the reed vlves. As the piston ners ottom ded center, ir from the crnkcse is forced through the trnsfer system into the cylinder. As the crnkshft continues to rotte the exhust nd intke ports close. With these ports closed, fuel cn e injected into the cylinder. The PCM will receive signl from the throttle position sensor (TPS), engine temperture sensor (TS) nd the crnk position sensor (flywheel speed nd position sensor). With this informtion, the PCM refers to the fuel clirtion (mps) to determine when to ctivte (open nd close) the injectors nd fire the ignition coils. With the piston in the correct position, the PCM opens the fuel injector, 744.6 kp (108 psi) fuel is dischrged into mchined cvity inside the ir chmer of the ir/fuel ril. This mixes the fuel with the ir chrge. Next the direct injector will open, dischrging the ir/fuel mixture into the comustion chmer. The direct injector directs the mixture t the owl locted in top of the piston. The piston s owl directs the ir/fuel mixture into the center of the comustion chmer. This ir fuel mixture is then ignited y the sprk plug. Compressor Notes: To id in strting when the ir ril pressure is low nd efore the compressor hs time to uild pressure, some direct injectors re held open y the PCM. This llows the compression from inside the cylinders to pressurize the ir ril fster (1 or 2 strokes, or 60 of crnkshft rottion). Idle Notes: Idle qulity is controlled y fuel volume nd fuel timing. The throttle shutter will e open t idle speed. The shift switch is mounted on the exhust dptor plte nd is ctivted y cm/notch in the upper shift shft. The switch hs closed circuit when the engine is in ger (forwrd or reverse) nd n open circuit when the engine is in neutrl. The switch is monitored y the PCM. The PCM will chnge fueling, timing nd RPM limit ccording to whether the engine is in ger or in neutrl. The TPS signls the PCM to chnge the fuel nd sprk without movement of the throttle shutters. The throttle cm is mnufctured to llow the TPS sensor shft to move efore opening the throttle shutter. 90-889785 APRIL 2003 Pge 3B-23
Testing Electric Fuel Pump Pressure Output Low Pressure Electric Fuel Pump 1. Connect Dul Fuel/Air Pressure Guge [91-852087A1/A2/A3] to Schrder vlve on VST. Guge should indicte 137.9 206.8 kp (20 30 psi). o57416 -Low pressure electric fuel pump Schrder vlve o59586 Pge 3B-24 90-889785 APRIL 2003
High Pressure Electric Fuel Pump DIRECT FUEL INJECTION 1. Instll Pressure Guge Assemly 91-852087A1/A2/A3 to fuel ril pressure test vlve. NOTE: After 15 seconds of crnking engine with strter motor, fuel pressure guge should indicte 744.6 ± 13.8 kp (108 ± 2 psi). 91-852087A1/A2/A3 o59607 -Fuel pressure guge [should indicte 744.6 ± 13.8 kp (108 ± 2 psi)] -Fuel pressure test vlve (ottom of fuel ril) 90-889785 APRIL 2003 Pge 3B-25
Fuel Mngement Assemly Removl CAUTION Fuel system must e led off prior to removl of fuel system components. WARNING Drin fuel from vpor seprtor tnk (VST) into suitle continer. Even though VST hs een drined, fuel my still remin in fuel rils nd hoses. Norml precutionry procedures should e dhered to while working with the fuel system. Avoid sprks, smoking nd open flme while in the presence of liquid fuel or fuel vpors. NOTE: Use Fuel/Air Pressure Guge 91-16850--1 or 91-852087A1/A2/A3 to de-pressurize ir hose first nd then fuel hose. 1. De-pressurize fuel system. e c -Air pressure guge -Fuel pressure guge c -Air pressure port d o59594 d-fuel pressure port (Design 1) e -Fuel pressure port (Design 2) Pge 3B-26 90-889785 APRIL 2003
2. Cut cle tie securing VST vent hose. 3. Plce suitle continer underneth vpor seprtor drin fittings. Turn respective relese screw to llow fuel to drin from fitting. Use ruer hose connecting drin fittings to direct fuel into suitle continer. After fuel is drined from VST, close off ech relese screw nd rettch hose to ech drin fitting. 4. Disconnect wter seprtor sensor connector. e c d o00526 -Cle ties -Relese screws c -Wter seprtor sensor led d-ruer hose e -Drin fittings 5. Disconnect electric fuel pump hrness connector. o59610 -Electric fuel pump connector 90-889785 APRIL 2003 Pge 3B-27
6. Remove the inlet fuel hose from the pulse fuel pump. 7. Remove pulse fuel pump vcuum hoses (2 ech). 8. Remove the fuel outlet hose nd fuel return hose on vpor seprtor tnk (VST). 9. Remove 3 mounting olts nd remove seprtor. e d e c -Fuel inlet hose to pulse pump -Fuel outlet hose (disconnect t fuel ril) o00883 c -Fuel return hose d-mounting olts e -Pulse pump vcuum hoses Pge 3B-28 90-889785 APRIL 2003
10. Remove throttle rm screw nd throttle cle pltform screw. 11. Disconnect MAP sensor, ir temperture sensor nd throttle position sensor hrness connectors. o00712 c e d -Throttle rm screw -Throttle cle pltform screw c -MAP sensor connector o00694 d-air temperture sensor connector e -Throttle position sensor connector 90-889785 APRIL 2003 Pge 3B-29
12. Remove 9 screws securing ir plenum nd remove plenum/throttle ody ssemly. o00707 -Screws Pge 3B-30 90-889785 APRIL 2003
Air Temperture Sensor Removl 1. Disconnect sensor hrness. 2. Unscrew sensor from ir plenum. DIRECT FUEL INJECTION o59574 -Air temperture sensor hrness connector -Air temperture sensor Air Temperture Sensor Instlltion 1. Screw sensor into ir plenum. 2. Reconnect sensor hrness. TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 1 TEMPERATURE SENSOR 13 1.4 90-889785 APRIL 2003 Pge 3B-31
MAP Sensor Removl 1. Disconnect wiring hrness. 2. Remove screw securing MAP sensor retiner nd remove sensor. c o59575 MAP Sensor Instlltion -MAP sensor -Screw c -Hrness connector 1. Instll sensor into ir plenum. 2. Reconnect sensor hrness connector. TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 1 SCREW (M6 x 16) 90 10.2 Pge 3B-32 90-889785 APRIL 2003
Throttle Plte Assemly Removl DIRECT FUEL INJECTION NOTE: The throttle plte ssemly is clirted nd preset for proper running chrcteristics nd emissions t the fctory. Other thn complete ssemly removl from the ir plenum, no further disssemly should e mde. 1. Remove 4 olts securing throttle plte ssemly to ir plenum nd remove ssemly. -Screws (4) o00356 -Throttle plte ssemly Throttle Plte Assemly Instlltion 1. Secure throttle plte ssemly to ir plenum with 4 screws. TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 4 SCREW 100 11.3 90-889785 APRIL 2003 Pge 3B-33
Reed Block Assemly Removl 1. Remove 9 screws securing cover to reed lock dptor plte. 2. Remove 15 screws securing reed lock dptor plte to crnkcse cover. 3. Remove 2 screws securing ech reed lock to dptor plte. d c e f g -Screws (9 ech) (M8 x 45) -Cover c -Adptor Plte d-screws (6 ech) (M6 x 20) e -Crnkcse Cover f -Reed Block (3 ech) g-screws (15 ech) (M8 x 35) Reed Block Assemly Instlltion NOTE: Replce ll gskets for lsting repir. 1. Secure ech reed lock with 2 screws to dptor plte. TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. d 6 SCREW (M6 x 20) 90 10.2 Pge 3B-34 90-889785 APRIL 2003
2. Secure dptor plte to crnkcse cover with 15 screws. Torque screws in following sequence. o00792 TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 15 SCREW (M8 x 35) 18 24.4 90-889785 APRIL 2003 Pge 3B-35
3. Reinstll cover with 9 screws. Torque screws in following sequence. 9 8 7 3 1 2 4 5 6 o00820 TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 9 SCREW (M8 x 45) 18 24.4 Pge 3B-36 90-889785 APRIL 2003
Vpor Seprtor Tnk Disssemly DIRECT FUEL INJECTION 1. Remove 2 screws securing pulse fuel pump to VST nd remove pump. Refer to Section 3A for disssemly, inspection nd ressemly of pulse fuel pump. -Pulse fuel pump o59376 -Screws 2. Remove fuel/wter seprtor filter from VST. Inspect filter O-rings for cuts or risions. Replce O-rings s required. Inspect filter element for deris. Remove deris or replce element s required. c o59372 o59375 -Fuel/wter seprtor filter -O-rings c -Filter element 90-889785 APRIL 2003 Pge 3B-37
3. Remove wter sensor from VST nd inspect for deris or corrosion. Clen or replce s required. Inspect sensor O-ring for cuts or rsions. Replce s required. o59370 o59371 -Wter sensor -O-ring 4. Remove 9 screws securing VST cover nd remove cover. Inspect cover seling ring for cuts or risions. Replce s required. o59374 o59378 -Screws (9) -Seling ring Pge 3B-38 90-889785 APRIL 2003
5. Loosen screw securing flot ssemly nd remove flot. Inspect flot for deteriortion or fuel retention. Replce flot s required. Inspect flot needle nd set for wer, deris or corrosion. Replce needle nd set s required. -Flot -Screw c o59342 c -Flot needle 6. Remove 2 screws securing low pressure fuel pump. 7. Remove low nd high pressure pumps from VST. Disconnect electricl connectors from ech pump. Inspect O-rings on ech pump nd on hrness for cuts or risions. Replce s required. c e e o59378 d e d c o59377 -Screws -Low pressure pump c -High pressure pump d-electricl connectors e -O-rings 90-889785 APRIL 2003 Pge 3B-39
Fuel Flow Director Components COMPONENTS c o00815 -Fuel director insert -Sel c -Sel ASSEMBLY VIEW d c e o00816 -High pressure fuel pump -Sel c -Fuel director insert d-check vlve e -Sel (instll on fitting) Pge 3B-40 90-889785 APRIL 2003
Vpor Seprtor Tnk Ressemly DIRECT FUEL INJECTION 1. Apply light oil to fuel pump elow O-rings to id instlltion into vpor seprtor. 2. Align gsket etween fuel pump nd VST. Secure fuel pump to VST with 2 screws. 3. Retorque ssemly screws. e c d c o59376 -Elow -Fuel pump c -Assemly screws d-attching screws e -Gsket (hidden) TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. c/d 4 SCREW 60 6.8 4. Apply light oil to wter sensor O-ring nd reinstll sensor in VST. o59371 o59370 -Wter sensor -O-ring 90-889785 APRIL 2003 Pge 3B-41
NOTE: If the fuel pump hrness must e replced, the new hrness must e routed through the VST csting efore instlling the RED nd BLACK wire pins into the hrness connector. To ensure correct electricl polrity, the RED wire pin must e instlled into the (A) pin receptcle nd the BLACK wire pin must e instlled into the (B) pin receptcle. After oth pins re instlled nd locked into the connector, slide the pin retiner over the hrness nd lock in plce on the connector. c d e f o59373 -(A) pin receptcle -Pin retiner c -RED wire d-black wire e -(B) pin receptcle f -Connector Pge 3B-42 90-889785 APRIL 2003
5. Apply light oil to electric fuel pump O-rings nd pump hrness O-rings. 6. Attch electricl hrnesses to ech fuel pump. Secure high pressure pump hrness to pump with cle tie. c o59377 -O-rings -Electricl hrness c -Cle tie 7. Instll oth fuel pumps into VST. Secure low pressure pump with retiner nd 2 screws. -Screws -Retiner c -Low pressure pump d-high pressure pump c d o59378 TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 2 SCREW 22 2.5 90-889785 APRIL 2003 Pge 3B-43
8. Secure flot, needle nd pivot pin ssemly to seprtor cover with screw. d c o59382 -Flot -Needle c -Pivot pin d-screw TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. d 1 SCREW 10 1 9. Instll cover seling ring on VST. Secure cover to VST with 9 screws. o59378 -Seling ring -Screws o59374 TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 9 SCREW 37 4.2 Pge 3B-44 90-889785 APRIL 2003
10. Apply 2-4-C with Teflon to fuel/wter seprtor filter O-rings. Thred filter into VST cover until filter sets. 95 o59372 o59375 -Fuel/Wter seprtor filter -O-rings Tue Ref. # Description Mercury Prt Numer Quicksilver Prt Numer 95 2-4-C with Teflon 92-802859A1 92-802859Q1 90-889785 APRIL 2003 Pge 3B-45
Air Plenum Instlltion Secure plenum to crnkcse with 9 screws. Torque olts in sequence shown. -Air plenum o00707 -Screws Vpor Seprtor Instlltion TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 9 SCREW (M8 x 45) 18 24.4 1. Secure vpor seprtor to ir plenum with 3 olts. 2. Reconnect pulse fuel pump vcuum hose. 3. Connect fuel inlet hose to pulse pump. IMPORTANT: Only use tool 91-803146T (or Snp-On equivlent YA3080) to crimp full circle clmps. Using different tool could result in crimp tht is too loose, or too tight. Do not use screw type metl hose clmp s it my dmge hose. 4. Secure fuel outlet hose with 15.3 mm full circle clmp (54-856880) using crimping tool 91-803146T. Pge 3B-46 90-889785 APRIL 2003
5. Connect fuel return hose to vpor seprtor. Secure hose with retiner nd screw g d c f e d d -Screws -Pulse pump vcuum hoses c -Inlet fuel hose d-fuel return hose e -Retiner f -Screw g-outlet fuel hose o00882 TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 3 SCREW (M8 x 60) 18 24.4 f 1 SCREW (M6 x 12) 90 10.2 90-889785 APRIL 2003 Pge 3B-47
Fuel Ril Removl CAUTION Fuel system must e led off prior to removl of fuel system components. NOTE: Use Fuel/Air Pressure Guge 91-16850--1 or 91-852087A1/A2 to de-pressurize ir hose first nd then fuel hose. 1. De-pressurize fuel system. 2. Remove fuel injector hrness from ech injector y compressing spring clip with flt tip screw driver while pulling on connector. c e d f 57798 o54871 -Fuel pressure port (ottom of fuel ril)(design 1) -Air pressure port c -Fuel injector o59586 d-hrness connector e -Spring clip f -Fuel pressure port (Design 2) Pge 3B-48 90-889785 APRIL 2003
NOTE: Alwys remove fuel/ir hose nd fitting together y removing fitting retiner rther thn cutting clmps. IMPORTANT: If ir hose is removed from red fitting, replce hose, s interior surfce of hose will e dmged during removl. 3. Remove llen screws securing ir nd fuel hose retiners. 4. Remove fuel, wter nd ir hoses from fuel ril. c o59609 e o59592 d o59605 -Fuel hose -Wter hose c -Fuel hose retiner llen screws d-air hose retiner llen screws (ottom of ril) e -Air hose 90-889785 APRIL 2003 Pge 3B-49
NOTE: It is recommended tht direct injectors remin in the cylinder hed (if they re not to e replced) while removing the fuel ril. The direct injectors hve teflon sel which my expnd if the injector is removed from the hed. This expnsion my cuse reinstlltion difficulty or require the replcement of the sel. 5. Remove 2 nuts securing fuel ril. -Nuts o59602 6. As fuel ril is removed, use flt tip screw driver to hold direct injectors in cylinder hed. -Fuel ril o59601 -Direct injectors NOTE: The fuel ril contins 3 fuel injectors, 1 fuel fuel regultor, nd 1 ir regultor. Pge 3B-50 90-889785 APRIL 2003
NOTE: Ech fuel/ir inlet or outlet hose dptor hs 2 O-ring sels. These O-rings should e inspected for cuts or risions nd replced s required when fuel ril is disssemled for clening. f i l e j g c d k h o00774 -Fuel injector -Fuel regultor c -Air regultor d-coolnt outlet to tell-tle e -Excess fuel return to VST f -Wter inlet for cooling fuel ril g-excess ir to muffler h-751.5 kp (109 psi) fuel i -655 kp (95 psi) ir j -Air pressure Schrder vlve k -Fuel pressure Schrder vlve (Design 1) l -Fuel pressure Schrder vlve (Design 2) 90-889785 APRIL 2003 Pge 3B-51
FUEL INJECTOR REMOVAL 1. Remove 2 screws securing injector. NOTE: Use cotter pin extrctor tool in pry holes to remove injectors. 2. Gently pry up on injector to loosen O-ring dhesion nd remove injector. o57970 o57967 -Screws -Pry holes 3. Inspect fuel injector orifices for foreign deris, O-rings for cuts or risions, nd plstic components for het dmge. Replce components s required. 4. An ohm test of the fuel injector my e mde y connecting test leds to injector terminls. Ohm reding should e 1.8 ± 0.1 ohm. c o56124 o56002 -Fuel injector -Fuel nozzle c -O-rings Pge 3B-52 90-889785 APRIL 2003
FUEL INJECTOR INSTALLATION DIRECT FUEL INJECTION NOTE: Apply nti-seize grese (otin loclly) or 2-4-C with Teflon to fuel injector ttching screw threds. 1. Insert fuel injector into fuel ril with connector pins fcing (inwrds) towrds center of engine. NOTE: Turn injector ck nd forth slightly to set injector O-rings in fuel ril while securing injector with retiner nd 2 screws. 95 95 -Injector -Retiner o57970 c -Screws Tue Ref. # Description Mercury Prt Numer Quicksilver Prt Numer 95 2-4-C with Teflon 92-802859A1 92-802859Q1 TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. c 2 SCREW 70 8 90-889785 APRIL 2003 Pge 3B-53
Fuel Pressure Regultor The fuel regultor is locted on the port fuel ril. o59587 -Fuel pressure regultor The fuel pump is cple of delivering more fuel thn the engine cn consume. Excess fuel flows through the fuel pressure regultor, interconnecting pssges/hoses, fuel cooler, nd ck to the vpor seprtor tnk. This constnt flow of fuel mens tht the fuel system is lwys supplied with cool fuel, therey preventing the formtion of fuel vpor ules nd minimizing the chnces of vpor lock. The fuel pressure regultor is clirted to rise the fuel pressure to 96.5 kp (14 psi) ove the ir pressure. The fuel regultor is mounted on the fuel ril, ner the top. This regultor relies on oth ir nd spring pressure to control the fuel pressure. Inside the regultor ssemly is 14 l. spring, this spring holds the diphrgm ginst the diphrgm set. The contct etween the diphrgm nd diphrgm set closes the pssge etween the incoming fuel [from the electric fuel pump] nd the fuel return pssge. When the engine is not running (no ir pressure on the spring side of the diphrgm) the fuel pressure required to move the diphrgm is 96.5 kp (14 psi). When the engine is running, ir pressure from the ir compressor 648.1 kp (94 psi) is routed through the ir pssges, to the spring side of the fuel pressure regultor diphrgm. The ir pressure 648.1 kp (94 psi) nd spring pressure 96.5 kp (14 psi) comine to regulte system fuel pressure to 744.6 kp (108 psi) - or 96.5 kp (14 psi) higher thn the ir pressure in the DFI system fuel/ir rils. Pge 3B-54 90-889785 APRIL 2003
FUEL PRESSURE REGULATOR CUTAWAY Regultor Closed 1 2 3 4 13 5 1 DIRECT FUEL INJECTION Regultor Open 2 3 4 5 12 7 6 7 6 11 8 11 8 10 10 9 9 1 -Top cover 2 -Expnsion plug 3 -O-ring 4 -Spring retiner 5 -Spring 6 -O-ring 7 -Diphrgm set 8 -Air ril 9 -Air pssge (from ir compressor) 10 - Fuel return pssge (to vpor seprtor) 11 - Fuel inlet pssge (from electric fuel pump) 12 - Diphrgm ssemly 13 - Clirtion screw (do not turn) 90-889785 APRIL 2003 Pge 3B-55
FUEL REGULATOR REMOVAL 1. Remove 4 screws securing regultor nd remove regultor. 2. Inspect regultor diphrgm for cuts or ters. 3. Inspect regultor housing O-ring for cuts nd risions. Replce components s required. c e d f o57968 o57969 -Screws -Fuel regultor c -Diphrgm d-spring e -Cup f -O-Ring Pge 3B-56 90-889785 APRIL 2003
FUEL REGULATOR INSTALLATION DIRECT FUEL INJECTION NOTE: Apply light cot of 2-4-C with Teflon to diphrgm surfce nd O-ring to id in the retention of diphrgm nd O-ring on fuel ril during ressemly. c e e d o57968 95 95 -Diphrgm -O-ring c -Spring o57975 d-cup e -Screws Tue Ref. No. Description Mercury Prt Numer Quicksilver Prt Numer 95 2-4-C with Teflon 92-802859A1 92-802859Q1 1. Position diphrgm on fuel ril. 2. Position O-ring on fuel ril. 3. Position spring nd cup onto diphrgm. NOTE: Apply nti-seize grese (otin loclly) or 2-4-C with Teflon to regultor ttching screw threds. 4. Plce cover over spring/cup/diphrgm ssemly. Plce the lignment pins from the specil tool (91-889431) through two of the regultor cover mounting holes nd thred them into the corresponding threded holes in the fuel ril. o00205 -Alignment Pins 90-889785 APRIL 2003 Pge 3B-57
5. Push the regultor cover ginst the fuel ril. While holding the cover down instll two cover retining screws through the open holes in the cover. Thred the two screws down until the hed of the screw mkes contct with the cover. Do not torque screws t this time. o00204 -Screw 6. Remove the lignment pins nd instll the two remining screws. -Screws o56126 TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 1st torque 5.6 Nm e 4 SCREW (50 l. in.); 2nd torque 7.9 Nm (70 l. in.) Pge 3B-58 90-889785 APRIL 2003
Air Pressure Regultor The ir pressure regultor is locted on the fuel ril. DIRECT FUEL INJECTION -Air pressure regultor o59585 The ir pressure regultor is designed to limit the ir pressure inside the rils to pproximtely 648.1 kp (94 psi). The ir regultor uses spring (pressure) to control the ir pressure. This spring 648.1 kp (94 psi) holds the diphrgm ginst the diphrgm set. The contct re locks (closes) the ir inlet pssge from the excess ir, return pssge. As the ir pressure rises (elow the diphrgm), it must rech pressure equl to or greter thn the spring pressure holding the diphrgm closed. Once this pressure is chieved, the spring compresses, llowing the diphrgm to move. The diphrgm moves wy from the diphrgm set, llowing ir to exit through the diphrgm set, into the excess ir pssge leding to the ir plenum. 90-889785 APRIL 2003 Pge 3B-59
Air Regultor Trouleshooting Correct ir pressure nd volume is criticl to proper opertion. Although ir pressure guge my show correct pressure, it does not confirm good volume. Air pressure should e mesured t the ir schrder vlve locted ner the middle of the fuel ril ssemly. Is ir pressure within [641.2 668.8 kp (93 97 psi)] rnge t neutrl idle position? No Yes Momentrily pinch off ir dischrge hose. Does pressure rise very quickly to pproximtely 744.6 kp (108 psi) or higher? Momentrily pinch off ir dischrge hose. Does pressure rise very quickly to pproximtely 744.6 kp (108 psi) or higher? No Yes No Yes Ostruction t compressor inlet or outlet or filed compressor. Air regultor OK. Compressor output low. Check compressor. Air compressor output nd volume OK. Air regultor fulty. Inspect regultor diphrgm, spring nd cup. Air compressor output nd volume OK. Regultor OK. Regultor Closed 1 2 1 Regultor Open 2 12 3 4 12 3 4 11 6 5 6 5 10 9 7 10 9 7 8 8 1 -Top cover 2 -Expnsion plug 3 -Spring retiner 4 -Vent 5 -Spring 6 -Diphrgm set 7 -Air ril 8 -Air pssge (from ir compressor) 9 -Excess ir pssge (to exhust dptor) 10 - Fuel inlet pssge (from electric fuel pump) 11 - Diphrgm ssemly 12 - Clirtion screw (do not turn) Pge 3B-60 90-889785 APRIL 2003
AIR REGULATOR REMOVAL DIRECT FUEL INJECTION NOTE: Due to the stiffness of the regultor spring, it is recommended tht Regultor Instlltion Tool 91-889431 e utilized when removing the ir regultor cover. Clen re re round regultor prior to disssemly to keep deris out of fuel system. 1. Remove two opposing screws from regultor cover nd instll regultor instlltion tool. o59360 2. With instlltion tool pplying pressure to regultor cover, remove remining cover screws. 3. Loosen instlltion tool nd remove cover. o59357 o59356 90-889785 APRIL 2003 Pge 3B-61
4. Inspect regultor diphrgm for cuts or ters. Replce s required. c d e -Screws -Air regultor cover c -Diphrgm AIR REGULATOR INSTALLATION o57974 d-spring e -Cup NOTE: Apply light cot of 2-4-C with Teflon to diphrgm surfce to id in the retention of diphrgm on fuel ril during ressemly. 1. Remove fuel ril from engine nd plce ril in horizontl position when ssemling ir regultor to ril to prevent dmge to diphrgm. NOTE: Mount fuel ril in vice to keep ril stle while ressemling. 2. Position diphrgm, spring nd cup onto fuel ril with fuel ril in horizontl position. NOTE: Apply nti-seize grese (otin loclly) or 2-4-C with Teflon to regultor ttching screw threds. NOTE: Due to the stiffness of the regultor spring, it is recommended tht Regultor Instlltion Tool 91-889431 e utilized when instlling the ir regultor cover. c -Cup -Spring c -Diphrgm Pge 3B-62 90-889785 APRIL 2003
3. Position cover over diphrgm spring nd instll Regultor Instlltion Tool 91-889431. -Regultor Instlltion Tool (91-889431) o59356 4. Gently pply pressure to cover with instlltion tool until cover is just seted ginst fuel ril. Do not over tighten center screw during instlltion or dmge to regultor cover my occur. o59357 5. Instll two retining screws. Remove instlltion tool. Instll remining two screws. 95 95 o59360 -Screws NOTE: After instlltion of ril on engine, verify function of regultor with pressure guge nd check for ir leks using sopy wter. Tue Ref. No. Description Mercury Prt Numer Quicksilver Prt Numer 95 2-4-C with Teflon 92-802859A1 92-802859Q1 TORQUE REF. NO. QTY. DESCRIPTION l-in l-ft Nm. 4 SCREW 70 8 90-889785 APRIL 2003 Pge 3B-63
Fuel Ril Clening Direct Injector Removl After ll fuel injectors, ir regultor, fuel regultor, inlet hoses nd outlet hoses hve een removed, the fuel rils my e flushed out with suitle prts clening solvent. Use compressed ir to remove ny remining solvent. IMPORTANT: If mechnicl filure should occur in the ir compressor or direct injector ssemlies, the fuel ril nd ttched hoses should e removed nd flushed with suitle prts clening solvent to remove ny metl deris. 1. Remove hrness connectors from direct injectors. 2. Remove direct injector from cylinder hed using 91-883521 -Direct Injector (3 ech) -Direct Injector Removl Tool 91-883521 o00783 Pge 3B-64 90-889785 APRIL 2003
3. Inspect injector teflon seling ring (white) for signs of comustion lowy (teflon ring will e streked rownish lck). If lowy is present, replce teflon seling ring. If lowy is not present, seling ring my e reused. 4. Inspect O-rings nd teflon ring for cuts or risions. Replce components s required. 5. If teflon sel requires replcement, use Teflon Sel Instlltion Tool to slide new sel onto injector. Following instlltion of teflon ring, the Teflon Ring Sizing Tool cn e used to compress the teflon sel to id in the instlltion of the injector into the cylinder hed. c d e e o57983 -Teflon seling ring -O-ring c -Teflon sel 91-851980-1 d-sel Instlltion Tool (91-851980--3) e -O-ring f -Teflon Ring Sizing Tool (91-851980-2) f 90-889785 APRIL 2003 Pge 3B-65
NOTE: It is recommended tht digitl ohm meter e used due to it s improved ccurcy when mesuring smll ohm redings inherit with direct injectors. 6. An ohm test of the direct injector my e mde y connecting test leds to injector terminls. Ohm reding should e 1.3 ± 0.3 ohm. 7. An ohm test to determine if direct injector windings re shorted to ground cn e mde y connecting one ohm led to either injector pin while touching the other ohm led to the injector metl cse. There should e no continuity. If there is continuity, the internl windings re shorted nd the injector must e replced. o00051 o00052 -Direct injector ohm test (1.3 ± 0.3 ohm) -Direct injector short to ground ohm test (no continuity) Pge 3B-66 90-889785 APRIL 2003
Direct Injector Lek Test 1. Attch Gercse Lekge Tool to dischrge side of injector. DIRECT FUEL INJECTION -Gercse Lekge Tool (FT-8950) -Direct injector o57714 2. Pump up lekge tool to indicte 172.4-206.8 kp (25-30 psi). 3. Direct injector should not lek down more thn 3.5 kp (1/2 psi) in 1 minute. 4. If injector does not meet the ove specifictions, replce injector. NOTE: If cylinder lock is going to e replced, remove cup wshers from ech direct injector port y prying out with flt tip screwdriver. Reinstll wshers with retiners into new cylinder lock. Wshers provide tension etween direct injectors, cylinder hed nd fuel rils. -Cup wsher -Retiner o59600 90-889785 APRIL 2003 Pge 3B-67