Car overheating - But no water leaks

POlarSource · 10-28-2004, 03:05 PM

1995 GSX with 6 bolt swap.

The car is fine running around town but when I stay at a constant 3k RPM's the check engine light comes on. The DSM link says it is a Knock Sensor Malfunction. About a minute later the heat starts rising and eventually I have to pull over, wait for it to cool, then add water.

This all started happening after the inlet in my radiator busted off and I replaced it with one out of a GST I had laying around.

I have checked for leaks, replaced the thermostat, and bought a brand new radiator... And I still continue to have this problem.

Thank all of you for any help you can provide,

Tyler

DSM_23 · 10-28-2004, 03:29 PM

Maybe a bad Temp. Sensor?

POlarSource · 10-28-2004, 03:31 PM

The car is actually overheating, not just a bad reading.

ChrisFlo · 10-28-2004, 03:33 PM

have you checked the water pump?

POlarSource · 10-28-2004, 03:36 PM

What are some signs of a bad water pump? When I open the cap and turn the car on it eventually starts to flow.

Defiant · 10-28-2004, 04:25 PM

You may have a failed impeller in the water pump. How old is it?

POlarSource · 10-28-2004, 05:09 PM

I am not sure how old the waterpump is. How hard is it to replace?

Erics_silver2g · 10-28-2004, 05:16 PM

if it was a problem with the water pump shouldnt it be blowing cold air when you turn on the heater? because the pump wouldnt be pushing hot water through the heater core?

POlarSource · 10-29-2004, 11:03 AM

I am going to go ahead and replace the water pump. If anyone has any advice on the install I would greatly appreciate it.

ADrewzki · 10-29-2004, 11:34 AM

Quote:

Originally Posted by POlarSource

I am going to go ahead and replace the water pump. If anyone has any advice on the install I would greatly appreciate it.

Drain coolant (duh). Take off the necessary parts to get the timing belt cover off. Take off the pulley for the water pump (10mm). The bolts for the water pump will be a pita to access. For a 6 bolt, just make sure you get a gasket for the 1g. Nothing really too tricky about it imho.

ECLIPSEESPILCE · 10-29-2004, 04:01 PM

Before doing a water pump make sure there are no internal head gasket leaks. Your coolant might be going into the engine and out the tail pipe.

POlarSource · 10-29-2004, 04:03 PM

We did a compression test and we got 130-150 across the board.

ECLIPSEESPILCE · 10-29-2004, 04:15 PM

there is a kit that has a resivoier that is filled with a special liquid that is placed in the radiator fill hole. It allows you to draw air from the radiator to check for exhaust gasses.
It is called a block test.
http://www.arrowheadradiator.com/hea..._leak_test.htm
Here is crummy link but it shows the tool.
call around to a few shops and they might have one.
It only takes a few minutes to do.

realitytb · 10-29-2004, 10:09 PM

water pumps are way easy. make SURE THAT YOU REPLACE TIMING BELT ALONG WITH IT!! its a must.
But one sign to see if the pump is bad, wiggle it a bit. if it wiggles, then its bad. also, check the pressure in your radiator. i know that i had severe over heating problems after my car was painted, becuase my radiator got plugged from the dust related to painting my car. Also check your thermostat. if its bad, then thats an easy fix for most over heating problems.

POlarSource · 11-01-2004, 09:29 AM

Quote:

Originally Posted by ECLIPSEESPILCE

there is a kit that has a resivoier that is filled with a special liquid that is placed in the radiator fill hole. It allows you to draw air from the radiator to check for exhaust gasses.
It is called a block test.
http://www.arrowheadradiator.com/hea..._leak_test.htm
Here is crummy link but it shows the tool.
call around to a few shops and they might have one.
It only takes a few minutes to do.

Isn't this tool used to find out if you have a bad head gasket? If so, wouldn't I see if it was bad when I did a compression test?

POlarSource · 11-01-2004, 09:34 AM

Thank you realitytb and everyone. I am going to replace the water pump this next weekend.

ECLIPSEESPILCE · 11-01-2004, 05:01 PM

I have seen bad head gaskets when a compression test is good. When hot some act different than others. Kinda a stupid question but when you installed the other radiator did you connect the cooling fans? I am not trying to offend you but i have seen it happen.

POlarSource · 11-01-2004, 05:06 PM

Yeah I am sure I connected the fans. I have also checked to make sure it is kicking on.

Ok, that may make since. I seem to loose boost after my car warms up... Could this support your thery that it may be bad only when it gets hot?

ECLIPSEESPILCE · 11-01-2004, 05:19 PM

I have seen some pretty strange things and it is possible. I just dont want to see anyone waste time and money replacing good parts.

highpsi93tsi · 11-01-2004, 05:23 PM

you might have a blown headgasket. My water pump is fvcked. Leaking water out the bearing/seal under the pulley faster than I can put it in it. Shitty deal. Ive replaced the whole cooling system on this car after I do the water pump.

POlarSource · 11-05-2004, 12:51 PM

Can a head gasket that is only bad when it reaches a curtain temperature lower boost pressure? I have boost when the car isn't warmed up but when it does I don't. Also, if it was the head gasket shouldn't the oil be milkey?