Cooling Fan Thermostat

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1 1 Operation Diagram Optimum operating temperature in a -cooled engine is provided by a system that circulates coolant through engine block jacket radiator. The pump is mechanism that maintains constant flow of coolant. In most cases, pump is driven by a belt pulley system, where pulley receives power engine's drive belt, timing belt, or fan belt. Cooling Fan Thermostat Radiator Water Pump Pulley Mechanical Seal 4

2 2 Structure Components Water Pump Diagnostic Manual The structure of pump is comprised of following components: pulley hub, body, shaft, bearing, mechanical seal rotor (impeller). The shaft is mounted onto a bearing which is pressed into pump body. On one end of shaft, a pulley hub is attached, while or end is a rotor (impeller). The pulley hub transfers energy fan or timing belt into a rotation, spinning shaft, refore spinning rotor. The rotor n circulates coolant. A mechanical seal is installed to prevent leakage of coolant into bearing also supports shaft for smooth rotation. Vapor hole Hub (Pulley Seat) Shaft Mechanical Seal Rotor (Impeller) Stud bolt Bearing Weep hole The body of pump is equipped with a vapor hole a weep hole. The vapor hole relieves excess gas pressure seeping through mechanical seal. The weep hole bleeds off excess coolant seeping through mechanical seal. Both holes function as a safety to protect shaft bearing contamination. 5

3 33 AISIN AISINWater WaterPump PumpCharacteristics Characteristics Bearing Bearing Wear Wear Resistance Resistance Outer Outer ringring sealseal BallBall sealseal The The bearing bearing relieves relieves pressure pressure onon shaft shaft tension tension created createdbybyfanfanor ortiming timingbelt. belt.since Sincepressure pressureis is continuously continuously applied, applied, a high a high quality quality bearing bearing is is of of utmost utmost importance importance to to protect protect pump pump failing. failing. Shaft Shaft Mechanical MechanicalSeal Seal Leakage Leakage Resistance Resistance Bellows Bellows (rubber) (rubber) Sealing Sealing (carbon) (carbon) Maintaining Maintaining ringring (ceramic) (ceramic) The The mechanical mechanical seal seal prevents prevents coolant coolant leak leak as as well well as as support support rotation rotationof ofshaft. shaft.the Thestructure structureof ofairtight airtightseal seal durable durablematerials materialsused usedalso alsoprevents preventsunneeded unneedednoise noise vibrations. vibrations. Pump PumpRotor Rotor Corrosion Corrosion Resistance Resistance Quality Quality materials materials forfor rotor rotor areare a necessity a necessity to to create create maintain maintaincomplex complexgeometry geometryforforoptimization optimizationof ofcoolant coolant flow, flow, as as well well as as resisting resisting corrosion corrosion rust, rust, scaling scaling of of coolant coolant cavitation. cavitation. Pump PumpBody Body Quality Qualitymaterials materialsareareused usedto towithst withstheat, heat,vibration vibration corrosion. corrosion. Water Waterchannel channelis isdesigned designedwith withoptimal optimalflow flowof of coolant. coolant.positioning Positioningof ofvapor vaporhole hole weep weephole holearearekeykeyto to prevent prevent excess excess coolant coolant bearing bearing shaft shaft contamination. contamination. Vapor Vapor holehole Weep Weep holehole 66

4 44 Water Water Pump Pump Diagnostic Diagnostic Manual Manual Precautions Precautionsin inhling Hling DoDo not not manually manually turn turn pulley pulley before before installation installation ofof pump. pump.in In mechanical mechanical seal, seal, soft soft carbon carbon block block may may create create residue residue onon ceramic ceramic block, block, generating generating abnormal abnormal (squealing) (squealing) noises noises during during operation. operation. SealDamage DamageExample: Example: 1.1.Do Donot notdry dryturn turn pulley! pulley! 2.2.Seal Mechanical MechanicalSeal SealInner InnerView View Carbon Carbon block block WARNING! WARNING! Ceramic Ceramic block block DryDry turning turning willwill deposit deposit carbon carbon onto onto ceramic ceramic block, block, causing causing squealing squealing during during operation. operation. Dry Dry turning turning will will damage damage mechanical mechanical seal. seal. Pre-lubricate Pre-lubricate before before turning. turning. 3.Pre-lubrication 3.Pre-lubrication 4.4.Water Waterlevel level Submerse Submerse lower lower part part of of pump pump body body base base of of rotor. rotor. Caution: Caution: DoDo notnot submerge submerge weep weep hole hole or or vapor vapor hole hole in in.. Submerge Submerge pump pump body body below below redred lineline Precautions Precautions It isit recommended is recommended that that lower lower part part of of pump pump is submerged is submerged in in forfor approximately approximately 3 minutes 3 minutes prior prior to to installation. installation.this This is to is to form form a layer a layer of of between between carbon carbon ceramic ceramicblocks blocksin inmechanical mechanicalseal, seal, prevent preventabnormal abnormal (squealing) (squealing) noises noises being being generated. generated. (Some (Somenoise noisemay maybebeheard heardat atinitial initialstart-up, start-up,butbutwillwilldisappear disappearafter afterengine engine warm-up.) warm-up.) 77

5 5 Installation Procedure Flush radiator 2-3 times with while letting engine idle. This will remove scale, rust deposits sludge coolant system. Replace 2-3 times After engine is cooled down, drain step 1, remove old pump, gaskets foreign materials left on mounting surface. Thoroughly clean with non-abrasive solvent. If a sealant is needed, apply an even amount around pump. Wipe off excess make sure sealant(rtv) does not intrude into channel. Do not allow sealant into channel. Prevents foreign materials contaminating new pump mechanical seal. Prevents leakage mounting surface. Excess sealant material may damage mechanical seal, which may cause pump failure. 4 Install new pump in a diagonal (star) pattern apply torque specified by vehicle manufacturer. Allow sealant(rtv) to cure if applied. 1 5 Confirm that fan coupling is free of rust contaminants. After installation, verify run-out tolerances specified by manufacturer using a dial indicator. 6 Install fan belt or timing belt apply tension specified by manufacturer. 3 Even diagonal (star) pattern No foreign materials Prevents leakage mounting surface. Prevents body damage installation. Prevents body fractures caused by belt tension. Prevents fractures damage caused by backlash or wobble of pulley or fan coupling. Prevents fractures damages caused by belt tension. Prevents noise. 8

6 Water Pump Diagnostic Manual Refill with new coolant (LLC) to mixture amount volume specified by vehicle manufacturer. Bleed air completely to ensure engine, pump, radiatior reservoir are filled with manufacutrer specified amount of coolant. Reconfrim amount of coolant(llc) belt tension. Start engine look for leaks. Gurgling Gurgling OK! Insufficient amount or incorrect mixture of coolant (LLC) will cause abnormal wear of mechanical seal, which will cause coolant leak. Insufficient amount or incorrect mixture of coolant (LLC) will cause abnormal wear of mechanical seal, which will cause coolant leak. Air bubbles may create additional cavitation which will corrode rotor. Prevents coolant leak under normal operation. Prevents damage installation Caution Failure to follow recommended procedures may cause engine failure injury. Failure Rate by Cause (Customer complaints) Ors 23% Noise 36% Leak 41% More than 75% of failures are due to complaints related to coolant leaks noise occuring pump. To prevent most pump problems occuring, follow 4 key steps described in installation procedures steps: 1 Flush radiator coolant system regularly 6 Tighten belt to vehicle manufacture specified tension 7 Re-fill with new coolant (LLC) 8 Bleed air completely 9

6 Troubleshooting 1 Weep Hole Coolant Leak Condition The weep hole

Coolant leak may be occurring if re is fluid around weep hole or if

In Cause Contamination sludge has damaged mechanical seal, reducing

Cure Before installing new pump, flush cooling system 2-3 times let

Do not use sealants (RTV) when gaskets are supplied.

7 6 Troubleshooting 1 Weep Hole Coolant Leak Condition The weep hole protects bearings corrosion damage by preventing seepage of coolant into pump body. normal operation, traces of dried coolant may be visible around hole. Coolant leak may be occurring if re is fluid around weep hole or if reservoir tank reaches low coolant levels within about a month. In Cause Contamination sludge has damaged mechanical seal, reducing sealing performance. Cure Before installing new pump, flush cooling system 2-3 times let engine idle for about 3 minutes with old pump to remove any sludge deposit. Replace anti-freeze regularly at specified mixture fluid level. Do not use sealants (RTV) when gaskets are supplied. When sealants are necessary, apply evenly do not allow excess to enter channel. 1 Coolant degradation 38,000 km (23,000 miles) 4 years old New ATTENTION Older coolants have higher risks of leakage. Always flush radiator replace with new coolant. Replace coolant regularly. 10

8 Water Pump Diagnostic Manual 2 Fair Poor, leak weep hole Normal Large coolant bleed mark, dampness or Damaged dripping. Dried coolant residue. 3 Fair Poor, mechanical seal ceramic Normal Clean ceramic. Damaged 11 Accumulated sludge (Contaminated coolant).

9 6 Troubleshooting 2 Seepage Condition Seepage mounting surface Cause Deterioration of sealing performance caused by unevenly applied sealant (RTV) Deterioration of sealing performance caused by use of adhesives Sealants used on O-ring deteriorated elasticity of rubber Unevenly tightened bolts Contamination (dirt/grime) on mounting surface Mounting surface dented caused by mishling Fractured/deformed gasket Cure Use manufacturer s specified sealant if it is designated Do not use sealants when gaskets are supplied Do not use adhesives in place of sealants or gaskets Install new pump in a diagonal (star) pattern apply torque specified by vehicle manufacturer Clean mounting surface free of contaminants Do not re-use old gaskets previously applied sealant 12

10 Water Pump Diagnostic Manual 2 Excess torque of mounting 1 Poor application of sealant bolt Threads have been stripped. Unevenly tightened or over torqued. Sealant has interfered with mechanical seal causing leaks. 3 Poor cleaning of mounting 4 Sealant used on supplied gasket Insufficient accuracy on mounting surface. Gasket performance has degraded. surface 13

11 6 Troubleshooting 3 Overheating Condition Corrosion of impeller Fracture of bearing Internal corrosion of pump body Cause Old coolant Coolant deterioration Insufficient flushing of radiator Low concentration of coolant Lack of coolant Cure Discontinue use of old coolant Fully flush radiator Replace coolant with manufacturer's specified mixture fluid level Purge air system 2 Cavitation 1 Coolant degradation Contamination of pump body Impeller corrosion Cavitation 14

Water Pump Diagnostic Manual Coolant When replacing pump,

Corrosion of impeller No corrosion can be seen on impeller

Corrosion can be seen on impeller when coolant is degraded

12 Water Pump Diagnostic Manual Coolant When replacing pump, flush coolant system 2 to 3 times to wash out sludge, scale rust deposits. Replace coolant to manufacturer's specified mixture fluid level. Re-using or using degraded coolant will corrode body, impeller, mechanical seals. 2 Fracture caused by cavitation 1 Severely corroded impeller Corrosion of impeller No corrosion can be seen on impeller when coolant is clean. Corrosion can be seen on impeller when coolant is degraded (contaminated / deteriorated). Mileage: 48,000 km (30,000 miles) Period: Approximately 1.6 years Total mileage: 149,000 km (92,500 miles) Mileage: 7,500 km (4,700 miles) Period: Approximately 1 year Total mileage: 105,000 km (65,000 miles) 15

13 6 Troubleshooting 4 Abnormal Noises Condition Rumbling sound heard when manually turning pulley Abnormal wear at base of stud bolts Excessive run-out of pulley seat Cause Bearing fracture caused by excess belt tension Bearing was fractured due to excess vibrations caused by misalignment of parts such as fan coupling pulley Uneven torque of bolts resulted in bearing failure Contamination of pulley seat Cure Tighten belt tension to vehicle manufacturer specifications If fan coupling pulley is reused, confirm run-out with a dial indicator Replace fan coupling pulley with new on older vehicles or high mileage engines Confirm that bearing is lubed no rumbling sound is heard, replace if necessary Flecking at bearing Damage due to overload seepage 16

Water Pump Diagnostic Manual Trouble caused by incorrectly installed

pump bearing Cause Reused damaged fan coupling Fan coupling was not

when replacing pump If fan coupling is reused, ensure that: re is no

components are free of rust debris check for run-out with a dial

Bearing seal plate is broken or missing Grease has dried rust has

14 Water Pump Diagnostic Manual Trouble caused by incorrectly installed or damaged fan coupling Condition Fracture of pump body Fracture of pump bearing Cause Reused damaged fan coupling Fan coupling was not installed correctly (off-centered) Cure Install new fan coupling when replacing pump If fan coupling is reused, ensure that: re is no binding or play in bearing bearing seal plate is securely fastened components are free of rust debris check for run-out with a dial indicator 1 Enlarged view of a fan coupling 2 Fractured bearing Bearing seal plate is broken or missing Grease has dried rust has formed on bearings If usage is continued Severe rust build-up 17 3 Fractured body

15 7 Quick Reference Water Pump Failures Leakage Location Symptom Cause Foreign material caught in mechanical seal Rusting caused by coolant degradation Excess sealant (RTV) entered pump cavity Weep hole Rough surface of mechanical seal Burned mechanical seal Rust caused by coolant degradation Insufficient cleaning of radiator Engine started without coolant Fracture of mechanical seal or bearing Excessive pulley tension Mounting surface Body fracture Contamination (dirt/grime) Installation error Fractured/deformed gasket Cavitation Body fracture Insufficient removal of sludge on engine mounting surface Damage/deformation of mounting surface Sealant (RTV) applied unevenly Bolts tightened unevenly Gasket damaged in shipping Bolts tightened unevenly or an impact wrench was used Coolant degradation Insufficient air bleeding Insufficient flushing of radiator Excessive pulley tension Wobble of pulley Mounting screw fracture Bolts were tightened excessively 18

16 Water Pump Diagnostic Manual Water Pump Failures Abnormal noise Location Symptom Cause Bearing Noise: Rumbling Locked bearing Bearing fracture caused by excess belt tension Bearing fracture caused by excess vibration of fan coupling pulley Mechanical seal Noise: Whining Dry turning of pulley caused carbon residue to form on ceramic block Engine started without coolant Pulley Noise: Squeak Slipping belt (insufficient belt tension) Water Pump Failures Ors Location Symptom Cause Run-out of rotor Damaged crimp Corrosion caused by coolant degradation Insufficient flushing of radiator Impeller corrosion Impeller wear/corrosion Corrosion caused by coolant degradation Insufficient flushing of radiator Run-out of pulley or bearing Pressure Leak Excessive run-out of fan coupling pulley Contamination (dirt/grime) on mounting surface 19

ENGINE COOLING GROUP CONTENTS GENERAL INFORMATION SERVICE SPECIFICATIONS COOLANT SEALANT THERMOSTAT...

ENGINE COOLING GROUP CONTENTS GENERAL INFORMATION SERVICE SPECIFICATIONS COOLANT SEALANT THERMOSTAT... 14-1 GROUP 14 CONTENTS GENERAL INFORMATION 14-2 SERVICE SPECIFICATIONS 14-2 COOLANT 14-3 SEALANT 14-3 DIAGNOSIS 14-3 INTRODUCTION 14-3 TROUBLESHOOTING STRATEGY 14-3 SYMPTOM CHART 14-3 SYMPTOM PROCEDURES