Car overheated... thermostat? water pump?
04-02-2005, 03:18 PM
#1
Car overheated... thermostat? water pump? The car overheated on the interstate this afternoon and I towed it home.
Backing up a couple of days, I was doing some tuning a few days ago and when I came home I found that something had burped some doolant on the passenger side of the engine. I cleaned it off, figured it was the overflow resevoir, and confirmed the resevoir level.
Today I got a little heavy on the throttle to pass, and it seemed shortly after that my coolant temp started rising. I'd say it went from ~200 to ~260 in about two minutes. It shutoff when I came to a stop in the exit lane. I restarted it when the light tyurned green, then immediately made a u-turn into a parking lot and parked the car.
The engine was steaming under the hood, and I found that coolant was frickin' everywhere. The first thing I noticed was that the radiator cap was loose - as in not locked at all. I could lift it straight up.
At any rate, I had 1.5 gallons of Dexcool in the car as a result of the previous incident. I added the 1/2 jug, then added about 3/4gal of faucet water from a local store, then began topping it off with the new jug.
I had the laptop with me, so I forced both fans on until the ECT dropped to 183*. Started the car, kept topping it off until it remained flat near the neck of the radiator cap. I found it odd that the level remained above the overflow tube.
So as I was watching the level for a few minutes, the car spontaneously shuts off. I look at the gauge and it hit redline again. Even with both fans running, it only took a matter of minutes for it to overheat again. Eventually the battery died from running the fans.
However, it does seem like I've got a separate coolant problem. It appears the level is OK when it's warm, but abnormally low when cold.
I have an aftermarket 160* thermostat and the stock water pump. What do I need to do to isolate the issue(s)?
Backing up a couple of days, I was doing some tuning a few days ago and when I came home I found that something had burped some doolant on the passenger side of the engine. I cleaned it off, figured it was the overflow resevoir, and confirmed the resevoir level.
Today I got a little heavy on the throttle to pass, and it seemed shortly after that my coolant temp started rising. I'd say it went from ~200 to ~260 in about two minutes. It shutoff when I came to a stop in the exit lane. I restarted it when the light tyurned green, then immediately made a u-turn into a parking lot and parked the car.
The engine was steaming under the hood, and I found that coolant was frickin' everywhere. The first thing I noticed was that the radiator cap was loose - as in not locked at all. I could lift it straight up.
At any rate, I had 1.5 gallons of Dexcool in the car as a result of the previous incident. I added the 1/2 jug, then added about 3/4gal of faucet water from a local store, then began topping it off with the new jug.
I had the laptop with me, so I forced both fans on until the ECT dropped to 183*. Started the car, kept topping it off until it remained flat near the neck of the radiator cap. I found it odd that the level remained above the overflow tube.
So as I was watching the level for a few minutes, the car spontaneously shuts off. I look at the gauge and it hit redline again. Even with both fans running, it only took a matter of minutes for it to overheat again. Eventually the battery died from running the fans.
However, it does seem like I've got a separate coolant problem. It appears the level is OK when it's warm, but abnormally low when cold.
I have an aftermarket 160* thermostat and the stock water pump. What do I need to do to isolate the issue(s)?
Last edited by JimMueller; 04-02-2005 at 10:43 PM.
04-03-2005, 03:29 PM
#3
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Hrmmm, there's another thread about an overheating engine... One thing to check are the water pump gaskets. I know of at least 2 LS1s that have had problems with the original gaskets failing. Mine failed on the passenger side which might be where your coolant is coming from. GM supposedly redesigned the gasket to prevent separation of the rubber piece from the metal.
04-06-2005, 03:55 PM
#4
So the water pump is leaking pretty badly. Not sure how it wasn't apparent to the dealer tech. New water pump ~$225 w/ housing & gaskets. Conflicting opnions on whether to buy a whole new GM casting, or just go to Autozone and buy replacement internals for the stock casting. Thoughts?
Driver head appears to be warped 4-5/1000th's, although we're not sure if it's all in the same area (i.e., no more than 3/1000th's in a 6" square area, etc) at this time. I've got the old style heads which need the graphite gasket, which give me a little more leeway than the MLS... but is it enough? I'm not sure if the passenger head is warped.
The other head seems to have residue on the exterior gasket as well and that'll be replaced at the same time.
So I guess the question is, will the graphite gasket be sufficient, or am I looking at further problems down the road if I don't machine it? Probably another $500 to R&R the valvetrain and cut the head.
Driver head appears to be warped 4-5/1000th's, although we're not sure if it's all in the same area (i.e., no more than 3/1000th's in a 6" square area, etc) at this time. I've got the old style heads which need the graphite gasket, which give me a little more leeway than the MLS... but is it enough? I'm not sure if the passenger head is warped.
The other head seems to have residue on the exterior gasket as well and that'll be replaced at the same time.
So I guess the question is, will the graphite gasket be sufficient, or am I looking at further problems down the road if I don't machine it? Probably another $500 to R&R the valvetrain and cut the head.
04-06-2005, 07:03 PM
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It sounds like you just pissed it all out of the radiator cap that was not closed all of the way. It take a while running and adding coolant to get the air out when it runs dry. Just keep running it while you watch and keep filling it.
There is probably nothing wrong.
There is probably nothing wrong.
04-06-2005, 07:43 PM
#7
Originally Posted by fasteddyss
It sounds like you just pissed it all out of the radiator cap that was not closed all of the way. It take a while running and adding coolant to get the air out when it runs dry. Just keep running it while you watch and keep filling it.
There is probably nothing wrong.
There is probably nothing wrong.
Did you read the whole thread? Trending Topics
04-06-2005, 08:18 PM
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Originally Posted by JimMueller
Did you read the whole thread?
Anyways regarding the water pump, The new GM pumps use a different thermostat housing. Your 160 therm won't fit it. If you cam get a rebuild it will save you the cost of a new therm.
As for the heads, I would not take chances if you have it apart. Get the shaved and you can feel at peace.
Good Luck!!!
