Exhaust System. Table of Contents. Section 6A - Exhaust System

Transcription

1 Exhust System Exhust System Tle of Contents Section 6A - Exhust System Exhust System...6A-2 Importnt Informtion...6A-2 Cron Monoxide Poisoning...6A-3 Exhust Connections...6A-4 Exhust Connections with Emissions Control...6A-5 Exhust Through Hull Fittings...6A-7 Exhust Resontors...6A-7 Emissions Control Systems Overview...6A-9 Comustion...6A-9 Emissions...6A-10 Controlling Emissions With Ctlysts...6A-10 Oxygen Sensors...6A-12 6 A APRIL 2008 Pge 6A-1

2 Exhust System Specil Tools Kent Moore Oxygen Sensor Socket KN Kent Moore socket (or equivlent 7/8 in. utomotive oxygen sensor socket) Aids in the removl nd instlltion of oxygen sensors on products equipped with Emissions Control Exhust System Importnt Informtion NOTICE Improperly designing, instlling, or modifying the engine s exhust system cn introduce sewter or wter from condenstion into the comustion chmers, dmging the engine. The instlling deler or ot uilder is responsile for proper instlltion of the exhust system s explined in the instlltion instructions for the product. Engine dmge resulting from wter ingestion is not covered y the product wrrnty, unless the dmge is the result of defective prt supplied y the engine mnufcturer. The exhust system must e instlled in ccordnce with the specifictions contined in this section. Specil cre must e tken s the custom designed exhust systems used cn crete tuning effect tht cn cuse wter to e forced ck into the engine. The instructions in Checking for Wter Intrusion must e performed to ensure tht wter intrusion is not occurring. It is the ot mnufcturer's responsiility for ensuring tht wter intrusion does not exist with their unique exhust system.! WARNING Instlling the exhust system incorrectly cn led to serious injury or deth. When instlling or designing exhust systems, follow ll federl, stte, nd locl oting nd sfety stndrds for the mrket in which the ot will e sold. GLOSSARY Exhust system design nd instlltion cn ffect: Noise level. Performnce. Wter Intrusion. Cron monoxide levels. Component longevity. Wter lift muffler A muffler tht exhusts ove the inlet in order to muffle y lifting column of wter. Inline muffler A muffler tht hs n outlet tht is prllel nd level with the inlet. Collector A collection device tht joins two exhust nks into perpendiculr chmer without providing ny noise reduction. Pge 6A APRIL 2008

3 Cron Monoxide Poisoning GOOD VENTILATION Exhust System IMPORTANT: The following importnt informtion is covered in the owner's opertion, mintennce nd wrrnty mnuls. You my lso wnt to include this informtion in the ot owner's mnul. Cron monoxide is present in the exhust fumes of ll internl comustion engines including the outords, sterndrives, nd inord engines tht propel ots, s well s the genertors tht power vrious ot ccessories. Cron monoxide is dedly gs tht is odorless, colorless, nd tsteless. Erly symptoms of cron monoxide poisoning, which should not e confused with sesickness or intoxiction, include hedche, dizziness, drowsiness, nd nuse.! WARNING Cron monoxide poisoning cn led to unconsciousness, rin dmge, or deth. Keep the ot well ventilted while t rest or underwy nd void prolonged exposure to cron monoxide. Ventilte pssenger re, open side curtins, or forwrd htches to remove fumes. 1. Exmple of desired ir flow through the ot. POOR VENTILATION mc Under certin conditions, permnently enclosed or cnvs enclosed cins or cockpits with insufficient ventiltion my drw in cron monoxide. Instll 1 or more cron monoxide detectors in your ot. Although the occurrence is rre, on very clm dy, swimmers nd pssengers in n open re of sttionry ot tht contins or is ner n operting engine my e exposed to hzrdous level of cron monoxide. 1. Exmples of poor ventiltion while ot is sttionry: - Operting the engine when the ot is moored in confined spce. mc Mooring close to nother ot with its engine operting. 2. Exmples of poor ventiltion while ot is moving: - Operting the ot with the trim ngle of the ow too high. mc Operting the ot with no forwrd htches open (sttion wgon effect) APRIL 2008 Pge 6A-3

4 Exhust System Exhust Connections NOTICE Hot spots in exhust hoses cn dmge hoses nd cuse leks. Ensure tht dischrge wter from the exhust elow flows without restriction through ll hoses nd fittings. To void hot spots tht cn urn exhust hoses, instll the exhust hoses t the ngle shown elow. Instll hoses on exhust elow outlets so dischrge wter from the exhust elow flows round the entire inside dimeter of the hose. Correct Incorrect - Mximum mislignment +/ 5 degrees - Exhust outlet centerline (14 vs. crnkshft centerline) c - Exhust hose centerline e d c d - Angle vs. horizontl e - Horizontl (level surfce) Pge 6A APRIL 2008

5 Exhust System e d c exhust connection - Mximum mislignment +/ 5 degrees - Exhust outlet centerline (14 degrees vs. crnkshft centerline) c - Exhust hose centerline d - See chrt for ngle vs. horizontl e - Horizontl (level surfce) IMPORTANT: The exhust system supplied y Mercury MerCruiser is complint with the ABYC Stndrd P 1. If components re used in ny portion of the exhust system tht modify the design of the supplied system, it is the ot uilder's responsiility to ensure tht the new system complies with the ABYC Stndrds. Exhust system connections to components other thn those supplied y Mercury MerCruiser must use two stinless steel clmps with minimum width of 13 mm (1/2 in.) t ech joint. Secure ll exhust connections, including those t the exhust elow, with two hose clmps. Do not use spring tension clmps Hose clmps Exhust Connections with Emissions Control NOTICE Hot spots in exhust hoses cn dmge hoses nd cuse leks. Ensure tht dischrge wter from the exhust elow flows without restriction through ll hoses nd fittings APRIL 2008 Pge 6A-5

6 Exhust System To void hot spots tht cn urn exhust hoses, instll the exhust hoses t the ngle shown elow. Instll hoses on exhust elow outlets so dischrge wter from the exhust elow flows round the entire inside dimeter of the hose. Correct Incorrect c - Exhust outlet centerline - Prllel wit crnkshft centerline c - Exhust ngle 14 ± IMPORTANT: The exhust system supplied y Mercury MerCruiser is complint with the ABYC Stndrd P 1. If components re used in ny portion of the exhust system tht modify the design of the supplied system, it is the ot uilder's responsiility to ensure tht the new system complies with the ABYC Stndrds. Exhust system connections to components other thn those supplied y Mercury MerCruiser must use two stinless steel clmps with minimum width of 13 mm (1/2 in.)t ech joint. Secure ll exhust connections, including those t the exhust elow, with two hose clmps. Do not use spring tension clmps. Hose clmps Pge 6A APRIL 2008

7 Exhust Through Hull Fittings Exhust System Exhust fittings (flnges, outlets) must e equipped with n internl shutter nd externl flpper to prevent wter intrusion prolems. This is requirement on ll pplictions except wter lift mufflers, where it is still recommended. A vriety of fittings is ville through Mercury Precision Prts nd Accessories. NOTE: For exhust ccessories, refer to Section 10 Miscellneous Accessories. Exhust Resontors The design of the exhust pipe nd muffler system cn cuse tuning effect tht cn contriute to wter intrusion prolem. This tuning effect cn e cused y comintion of fctors, including ut not limited to: Configurtion of the exhust outlets. Design nd size of the muffler (if pplicle). Length of exhust hoses. Amount of ck pressure in the system. The interctive nture of these fctors mkes it difficult to predict which exhust system designs will e susceptile to the tuning effect. To ddress this sitution, Mercury MerCruiser hs developed exhust resontors tht re instlled ft of the exhust elow outlets, which help to rek up the reverse pulstions without ffecting engine performnce. Mercury MerCruiser recommends using resontors on ll models tht hve wter present fter wter intrusion testing, nd the exhust system is confirmed to meet ll specifictions, s outlined in this mnul. Resontors re typiclly more eneficil for lrge engines, ut cn e used on other models. The kit is ville through Mercury Precision Prts nd Accessories. Resontors re instlled s shown. Becuse of the criticl nture of the plcement of the resontor, Mercury MerCruiser will free license this technology to llow the resontor to e uilt into your muffler. Contct your product ppliction engineer for detils. The exhust resontor is positioned with the inside flt surfce t the preferred distnce of 43 cm (17 in.) from the front edge of the exhust hose. You cn reduce the 43 cm (17 in.) dimension cn to minimum of 33 cm (13 in.), if necessry. This dimension must e the sme on oth exhust outlets. The ot uilders must test to find the optimum resontor plcement for ech type of exhust system. IMPORTANT: Complete the wter intrusion test to ensure tht the resontors re instlled properly APRIL 2008 Pge 6A-7

8 Exhust System FOR PRODUCTS WITHOUT EMISSIONS CONTROL f c g d e Exhust resontor - Exhust hose c - Dimension to inside flt surfce of resontor cm (13 17 in.) d - No less thn 51 mm (2 in.) etween resontor nd exhust outlet or closest fitting e - Hose clmp positioned round center of resontor for retention f - Exhust outlet g - Exhust elow f c g e d - Exhust resontor - Exhust hose c - Dimension to inside flt surfce of resontor cm (13 17 in.) d - No less thn 51 mm (2 in.) etween resontor nd exhust outlet or closest fitting e - Hose clmp positioned round center of resontor for retention f - Exhust outlet g - Exhust elow Pge 6A APRIL 2008

9 Exhust System FOR PRODUCTS WITH EMISSIONS CONTROL d c f e - Exhust elow - Dimension to inside flt surfce of resontor cm (13 17 in.) c - Exhust resontor d - Exhust outlet e - No less thn 51 mm (2 in.)etween resontor nd exhust outlet or closest fitting f - Hose clmp positioned round center of resontor for retention c d e f g - Exhust outlet - Exhust resontor c - Dimension to inside flt surfce of resontor cm (13 17 in.) d - Exhust elow e - Exhust hose f - Hose clmp positioned round center of resontor for retention g - No less thn 51 mm (2 in.)etween resontor nd exhust outlet or closest fitting Type nd configurtion of exhust outlet. Length of exhust hose. Amount of ck pressure in exhust system. Emissions Control Systems Overview Comustion Comustion is rpid chemicl rection, clled oxidtion, in which fuel chemiclly comines with oxygen to produce het energy. Among other elements, ir contins oxygen nd nitrogen, nd gsoline contins hydrogen nd cron. These four primry elements comine chemiclly during comustion to form new chemicl compounds APRIL 2008 Pge 6A-9

10 Exhust System Emissions CARBON MONOXIDE (CO) HYDROCARBONS (HC) OXIDES OF NITROGEN (NOX) If comustion were complete, the oxidtion of ir nd gsoline would result in wter, cron dioxide, nd nitrogen, which re not hrmful to the environment. For comustion to e complete, it needs to occur t specific ir to fuel rtio clled the stoichiometric rtio (14.7:1 for gsoline). Although this rtio is idel for reducing hydrocrons (HC) nd cron monoxide (CO), it is len mixture tht cn e difficult or slow to ignite, reducing engine power nd efficiency. Since comustion is usully incomplete, not ll of the exhust gses urn, cusing emissions. All mrine engines must reduce the exhust emission of certin pollutnts nd hrmful gses to conform with stndrds legislted y the Environmentl Protection Agency (EPA). All engines sold in the stte of Cliforni must lso comply with the stndrds legislted y the Cliforni Air Resources Bord (CARB). In ccordnce with these stndrds, nd in preprtion of future stndrds, Mercury Mrine is working to reduce the following: cron monoxide (CO), hydrocrons (HC), nd oxides of nitrogen (NOx). Cron monoxide (CO) is poisonous gs creted y incomplete comustion of gsoline. If comustion occurs in n oxygen deficient environment, the limited mount of oxygen llows only one oxygen (O) tom to ond with con (C) tom, creting CO from prtilly urned fuel. Richer ir to fuel rtios crete more CO thn len rtios. Hydrocron (HC) emissions re cused y incomplete comustion of gsoline nd other hydrocron sed fuels. When gsoline urns, oxidtion occurs; however, some hydrocrons do not oxidize. Lower engine tempertures mke it hrder for the hydrocrons to oxidize. Therefore, some hydrogen nd cron toms remin onded nd pss through the exhust system s HC gses from unurned fuel. Oxides of nitrogen (NOx) is generic term for group of chemicl compounds tht contin nitrogen (N) nd oxygen (O) in vrying mounts (x). NOx is creted y overheted hydrogen nd oxygen. At extremely high tempertures, N toms cn comine with O toms to crete NOx. Unlike CO nd HC, which form when comustion tempertures re too low, NOx forms when comustion tempertures re too high. NOx itself is not hrmful. However, when exposed to sunlight, NOx comines with unurned hydrocrons to crete the visile ir pollutnt clled smog. Controlling Emissions With Ctlysts CATALYST COMPONENTS A ctlyst, or ctlytic converter, is device instlled into the engine's exhust system tht reduces the toxicity of emissions. Mercury MerCruiser engines use three wy ctlysts with the following components: Sustrte The sustrte is metlic foil core tht provides lrge surfce re for the wshcot. Wshcot The wshcot is pplied to the sustrte to ct s crrier for the ctlyst. This wshcot cretes n irregulr, porous surfce, providing more surfce re for the precious metl of the ctlyst. Ctlyst The ctlyst is comintion of precious metls pplied to the porous structure of the wshcot. The heted chemicl rection of exhust gses nd precious metls of the ctlyst reduce emissions. This ctlyst ssemly is then housed in the mntle. Pge 6A APRIL 2008

11 CATALYST OPERATION Exhust System Mntle The mntle is the tue tht contins the ctlyst. The mntle is instlled in the engine's exhust mnifold housing. Oxygen sensors Multiple oxygen sensors trnsmit emissions dt to the propulsion control module (PCM) to control emissions. Propulsion control module (PCM) Models with Emissions Control use PCM09 controller to mnge fuel delivery to the engine nd mintin CARB emissions stndrds. Mercury MerCruiser's engines with Emissions Control meet the CARB requirements for exhust emissions levels effective Jnury 2008 in the stte of Cliforni. These engines feture three wy ctlysts, which use comintion of pltinum, plldium, nd rhodium to convert hrmful emissions to sfe levels. A three wy ctlyst reduces emissions in the following wys: It reduces nitrogen oxides to nitrogen nd oxygen (2NOx xo 2 + N 2 ). It oxidizes cron monoxide into cron dioxide (2CO + O 2 CO 2 ). It oxidizes unurnt hydrocrons to cron dioxide nd wter (C 2 H 4 + 3O 2 2CO 2 + 2H 2 O) MAG exhust minfold shown 1 - Exhust gses from the comustion chmer 2 - Pre ctlyst oxygen sensor 3 - Ctlysts Post ctlyst oxygen sensor 5 - Reduced emissions APRIL 2008 Pge 6A-11

12 Exhust System Oxygen Sensors The Vzer 100 nd 3.0 MPI hve one ctlyst nd two oxygen sensors. All others hve two ctlysts nd four oxygen sensors. The oxygen sensors send oxygen informtion to the PCM efore nd fter the ctlysts in the exhust system. This dul sensor system provides closed loop monitoring system, ensuring required ir to fuel rtios nd emissions Reference Action 1 PCM clcultes ir fuel rtio. 2 Fuel system delivers the required ir/fuel rtio to the comustion chmer. 3 Comustion occurs (power stroke). 4 Exhust gses enter the exhust mnifold (exhust stroke) The first oxygen sensor sends signl to the PCM, delivering pre ctlyst oxygen informtion. The exhust gses pss through the ctlyst. Ctlyst rections oxidize hydrocrons (HC) nd cron monoxide (CO) nd reduce oxides of nitrogen (NOx). The second oxygen sensor sends signl to the PCM, delivering post ctlyst oxygen informtion. NOTE: Ech oxygen sensor is protected y 5 mp fuse. NOTE: Mercury MerCruiser engines do not depend on closed loop control to clculte ir f to fuel rtios t ll times. During some operting situtions, closed loop control is off, nd the PCM relies on its defult progrmming to mke these clcultions. Kent Moore Oxygen Sensor Socket KN Pge 6A APRIL 2008