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Forum namePerformance/Engine
Topic subjectengine overheating after rebuild (kinda long)
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i5&topic_id=126095
126095, engine overheating after rebuild (kinda long)
Posted by abnt89, Jun-15-09 03:30 PM
Ok..I replaced the water pump, thermostat, radiator cap, and all the hoses. I put as much coolant in through the thermostat housing as I could and then I filled the reservoir to the low mark. I started the car and it got up to operating temp just fine. There was coolant leaking out from under the exhaust manifold where the head meets the block but after 3-4 min it stopped leaking. It stayed at operating temp for about 10 min and then gradually went to about 3/4 way up the temp gauge before I turned it off. While it was doing this the coolant was boiling in the reservoir and coming out the overflow. It was still boiling 5 min after the car had been off. I didn't notice any smoke or steam coming from the exhaust. The top of the radiator was hot but I forgot to see if the bottom was too. The fan came on but I'm going to replace the thermostat again and the sensors tonight just to make sure. I searched around but couldn't find anything that was really like this. Do you think there could just be some air in the system? Or something worse...like the head gasket? TIA

-Anthony
126096, RE: engine overheating after rebuild (kinda long)
Posted by bullettdsm, Jun-15-09 03:57 PM
Originally posted by abnt89
There was coolant leaking out from under the exhaust manifold where the head meets the block but after 3-4 min it stopped leaking.

This should never happen after a rebuild. The headgasket is not like other seals and gaskets etc. It doesn't just fill up with fine particles and "fix itself" like some seals and gaskets. If indeed it was out of the headgasket, the head will need to come off and the problem will need to be found. Now are you sure that it was not another hose leaking?



126100, RE: engine overheating after rebuild (kinda long)
Posted by abnt89, Jun-15-09 06:32 PM
Originally posted by bullettdsm
This should never happen after a rebuild. The headgasket is not like other seals and gaskets etc. It doesn't just fill up with fine particles and "fix itself" like some seals and gaskets. If indeed it was out of the headgasket, the head will need to come off and the problem will need to be found. Now are you sure that it was not another hose leaking?


Well when I was filling it with coolant I spilled some and it very easily could of just been running down there from that. But it doesn't look to be any of the hoses. Somehow there are two holes in the coolant reservoir. Could this cause it? And what are some good ways of checking the system for air pockets and then getting rid of them? TIA
126102, RE: engine overheating after rebuild (kinda long)
Posted by freelancefool, Jun-15-09 08:22 PM
Let the car cool down, preferably over night. Crank it up and see if it still leaks at the head. If it does, since all the current coolant you spilled burned off, you have a head gasket leak.

What you may have seen was the head heating up enough to seal off against the block enough to keep the coolant from seeping out the front of the motor.
126104, RE: engine overheating after rebuild (kinda long)
Posted by abnt89, Jun-15-09 09:57 PM
Originally posted by freelancefool
Let the car cool down, preferably over night. Crank it up and see if it still leaks at the head. If it does, since all the current coolant you spilled burned off, you have a head gasket leak. What you may have seen was the head heating up enough to seal off against the block enough to keep the coolant from seeping out the front of the motor.


How would I have a head gasket leak already? The engine hasn't even been driven? The machinist that worked on the block bolted the head on. He said he didn't use that copper gasket sealant because the head gasket has teflon or something on it that is supposed to melt and seal up the head. At least thats what he said. He also told me to drive it tomorrow to see if it seals up at all from getting hot. My work is only about 5 miles away so I guess i'll try that unless you guys think this could hurt the engine.
126128, RE: engine overheating after rebuild (kinda long)
Posted by LLs420a, Jun-17-09 01:35 PM
I know that if the overflow resevoir isn't properly mounted, its possible that the power steering pulley can wear a hole through the side of the resevoir. Could this be the "second" hole you are referring to? Keep a close eye on your temp gauge to make sure you dont overheat if you're getting it out on the street
126130, RE: engine overheating after rebuild (kinda long)
Posted by abnt89, Jun-17-09 01:54 PM
Originally posted by LLs420a
I know that if the overflow resevoir isn't properly mounted, its possible that the power steering pulley can wear a hole through the side of the resevoir. Could this be the "second" hole you are referring to? Keep a close eye on your temp gauge to make sure you dont overheat if you're getting it out on the street


Yea, thats exactaly what happend to the reservoir. I fixed the hole for now until I can get a new one. I drove it hard yesterday for about 20 miles and it didn't overheat at all. So I guess I'll just keep an eye out for any coolant leaks for now. If anyone has any suggestions that would help a lot. Thanks
126132, RE: engine overheating after rebuild (kinda long)
Posted by LLs420a, Jun-17-09 02:28 PM
Sounds like youre on the right track. I actually hardwired my cooling fans to a toggle switch mounted inside the car, just because I dont trust ANYTHING on my car. lol. Also you can probably find another resevoir on ebay. I had the exact same problem with my resevoir and found a spare on ebay for 15 bucks shipped.
126134, RE: engine overheating after rebuild (kinda long)
Posted by abnt89, Jun-17-09 02:55 PM
Thanks man I didn't even think about looking on ebay for that reservoir but I'm going to do it right now. lol Thanks