Post Title: Re: Cooling system diagnosint - Water pump? (dusred)
Posted by: maxnix at 6:47 PM 8/8/2008
Whats left? The only thing that I can think of is the water pump. How can I tell for sure if it is the water pump?
Thanks
Post Title: Re: Cooling system diagnosint - Water pump? (dusred)
Posted by: maxnix at 6:47 PM 8/8/2008
Critical for thermostat, tank tops and water pump.
Post Title: Re: Cooling system diagnosint - Water pump? (dusred)
Posted by: jimbyjimb at 5:46 AM 8/9/2008
Since head gasket failure is extremely rare unless the engine has been overheated. You always check coolant for hydrocarbon gases [use the typical device] and measure pressure build up time and ramp up rate. To confirm.
Using aftermarket parts which are only 95-90% as efficient to new oem may reduce the safety spread.
Really difficult to diagnose without accurate temperature number and a time to rise chart, idle rpm, ambient temperature, ac on/off.
Many times overheats are somethings you forget like the rubber air surround around radiater allowing an air feedback fom engine compartment to the input side of rad. A restricted airflow condenser, dead auxillary electric fan in front of condenser. high idle rpm, more than 50% AF in coolant.
Post Title: Re: Cooling system diagnosint - Water pump? (Q45tech)
Posted by: dusred at 1:01 PM 8/9/2008
| Quote, originally posted by dusred » |
| Is there a way to test the AUX fan? |
It would also help us to help you if you would answer the questions asked.
Post Title:
Posted by: dusred at 12:25 PM 9/28/2008
To answer your questions, Tech, the water pump doesn't leak from the weep hole or make strange noises.
The car has been heated up but I have never let it get past the safe zone on the engine temp gauge.
What's the typical device you use to check for hydrocarbon gases?
I have only used OEM parts on my car.
What is this "rubber air surround" you speak of?
I just cleaned the air condenser so that shouldn't be a problem. I was suspecting the AUX fan because it didn't seem to be blowing as hard as it should be.
I really appreciate the help, Tech, and others on here.
Post Title: Re: (dusred)
Posted by: Paul Wall at 3:39 PM 9/28/2008
| Quote, originally posted by dusred » |
| The car has been heated up but I have never let it get past the safe zone on the engine temp gauge. |
Aluminum has little tolerance for over heating.
Modified by maxnix at 7:38 PM 10/10/2008
Post Title:
Posted by: dusred at 8:44 PM 9/28/2008
Lets say it did "overheat" how can I tell what damage was done? And if it did do damage to the engine/head gasket how can that effect the cooling system?
Post Title: Re: (dusred)
Posted by: Q45tech at 6:08 AM 9/29/2008
The point is tools are necessary along with technical education to use them. At least the ability to follow written instructions precisely.
Post Title: Re: Cooling system diagnosint - Water pump? (dusred)
Posted by: fixer at 3:06 PM 10/10/2008
When does it get hot? Will it sit at idle and overheat or only overheat while driving/cruising?
If you have access to a laser thermometer use it to take some temp readings of the radiator at a couple of points; top, bottom, and each side. There will be some temperature variation but not like a 100*F difference.
Post Title:
Posted by: dix at 3:37 PM 7/3/2009
Since a rad may only drop temp 10-15F from input to output.
Almost always the problems are a used old, dirty, bent fin radiator especially after 8 years [depending on mileage].
After market rads while they fit are made of thinner plastic and aluminum, their fin count per inch is less and generally under stress thay perform 10% less than new OEM.
While 10% less may not sound like much adegree here and there soon adds up causing the feedback system [thermostat vs pump] to lose control with a slow steady rise in coolant temperature.
Why it is important to create a graph of coolant vs ambient vs time in 15 second increments from a cold crank for 15 minutes [60 data points] idling in shade.
THEN turn AC on MAX and data log for another 10 minutes.
DO IT AND YOU WILL SEE what I am saying.
Unfortunately you need a CONSULT to see coolant temp as ecu sees coolant temp.
I drive non engineering techs battey with all my engineering data recovery.
BUT THE DATA NEVER LIES!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
The GREGORY HOUSE of Automotive Technology
AFTER ALL if you combust X amount of gasoline in Y time at Z efficiency an exact amount of HEAT is generated. The heat can only go 3 places sitting still..
Heat the air underhood, heat the coolamt, or flow out exhaust pipe
Post Title: Re: (Q45tech)
Posted by: dix at 12:01 PM 7/4/2009
Thanks
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