Engine overheating
Engine overheating Last night I got her up to about 160mph and my belt came off. I didnt realize this until my temp gauge was almost to the red and i quickly pulled over and shut if off and had it towed home. It looks like the coolant expanded and came out of the reservoir and made a bit of a mess. anyway, I got a new belt and fired her back up and added some coolant but now its still overheating. I thought ok I will jack up the front passenger side in order to get any air bubbles out while squeezing the hoses. It is still overheating. Everything else looks ok and it runs fine but could I have broke something that would keep it from running at operating temp. I have a 160 t-stat btw.
Also I noticed my radiator hoses got sucked closed right after this happened. they are not closed anymore but they feel empty and are in more of an oval shape now rather than circular. I looked under the oil cap and I found a bunch of yellowish looking foamy gunk under there. Im guessing this is just from the oil getting cooked when it got so hot.
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Joined: Apr 2009
Posts: 531
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From: Pocatello Idaho
The yellow stuff under the cap is most likely moisture in the oil. The best way I have found to bleed the cooling system of air is wait until the car is cold. Take the radiator cap off and start it. There is a small hose going into the radiator right under the cap. That needs to be shooting coolant back into the radiator. In my exp. once there is a steady stream of coolant coming out the air should be out.
I have been letting cool off in between tries and then starting it with the radiator cap off. I have the car jacked up right now to hopefully help any air bubbles rise to the top. It seems like the there is no coolant in the engine cause nothing is coming back to the radiator. I think the T-stat is locked up and its not sucking the coolant back into the engine. I think i might try pulling the hoses and t-stat and see whats going on in there.
If you have a known good t-stat I would pressure test the cooling system next...
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I did not replace the t-stat today but this is a newer 160 t-stat. It shouldnt be broken in less than 2k miles and a year. all i did was just look it over and play with the spring mechanisms and put it back together. Basically the coolant is just sitting in the radiator which is about 3/4 full. Not at any point is the engine sucking it down nor is anymore coolant coming back from the engine. the system just seems dead. Its got to be either my waterpump or the t-stat. I will try the boiling water trick and if the t-stat is busted I have a stocker I can throw in. Otherwise im narrowing it down to the waterpump. Does it sound normal that either the extra heat or maybe even revving high while driving fast killed either the water pump or the t-stat. Also, no leaks as of now.
EDIT: Just a thought....Assuming there is very little coolant in the engine and there is cold coolant in the radiator, could the t-stat just not be opening because it has no warm coolant to open it up? or will it just automatically open with the heat of the engine, not having anything to do with the coolant?
EDIT: Just a thought....Assuming there is very little coolant in the engine and there is cold coolant in the radiator, could the t-stat just not be opening because it has no warm coolant to open it up? or will it just automatically open with the heat of the engine, not having anything to do with the coolant?
Last edited by gmmusclecarman; Feb 2, 2010 at 10:54 PM.
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Verdad Gallardo I did the t-stat test and it opened so it works. I also pulled the upper radiator hose and there was really and coolant in there. I spun the pulley on the water pump freely and that also seemed perfectly fine.
I just ran it again and added a little bit of coolant. I also disconnected the upper radiator hose. I noticed that just a little bit of coolant went down but not even a drip came out of the upper radiator hose connection. Im just so damn confused I have no idea what to think.
Ok so doesnt look like the coolant leaked out of the radiator so it must have gone into the engine. I still think the t-stat isnt opening up even with it closed there will still be a small amount of coolant going through into the engine. So in theory shouldnt this small amount of coolant be going through the engine and back to the radiator? Therefore heating up the coolant in the radiator which should heat up the tstat, which then should open.
So either my waterpump is bad or my headgasket is leaking and just eating up the coolant. Oil looks ok to me and I was trying to check the exhaust for a sweet smell and white smoke. I didnt smell anything sweet in the exhaust and i couldnt tell if there was white smoke in the exhaust because it was too cold out.
Is there any other way to tell if the waterpump is bad? I have no idea how old this pump is or when or if it was ever replaced. It was the same one on the car when i got it and I just swapped it over to my new motor. Again, no leaks from the pump or noise from the bearings. It spins freely and seems fine to me. I am lost.
Ok so doesnt look like the coolant leaked out of the radiator so it must have gone into the engine. I still think the t-stat isnt opening up even with it closed there will still be a small amount of coolant going through into the engine. So in theory shouldnt this small amount of coolant be going through the engine and back to the radiator? Therefore heating up the coolant in the radiator which should heat up the tstat, which then should open.
So either my waterpump is bad or my headgasket is leaking and just eating up the coolant. Oil looks ok to me and I was trying to check the exhaust for a sweet smell and white smoke. I didnt smell anything sweet in the exhaust and i couldnt tell if there was white smoke in the exhaust because it was too cold out.
Is there any other way to tell if the waterpump is bad? I have no idea how old this pump is or when or if it was ever replaced. It was the same one on the car when i got it and I just swapped it over to my new motor. Again, no leaks from the pump or noise from the bearings. It spins freely and seems fine to me. I am lost.
you must have a huge pocket of air or something....... just allow the car to heat up with the radiator cap off and make sure the radiator is full. you must allow a few minutes of steam to come out of the radiator... that means the system is burping.
again if this doesnt work check the stat in boiling water.
i dont think its your head gasket because there would be a noticeable 30ft cloud of smoke if it was sucking down that much coolant.
again if this doesnt work check the stat in boiling water.
i dont think its your head gasket because there would be a noticeable 30ft cloud of smoke if it was sucking down that much coolant.
I did both of those two things. Ive let the car heat up as much as possible with the radiator full and cap off. Ive done this before and it worked fine. I dont know why it isnt working now. there was a decent amount of exhaust coming out but it was hard to tell if it was just the cold making it all visible or if it was actually coolant burning up.
Joined: Aug 2007
Posts: 24,241
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From: Turnin' Wrenches Infractions: 005
Try priming the system by pouring water down the upper radiator hose with a pitcher full of water so you can see how much its taking. Hose disconnect, motor cool and not running. 
Dude, take the t-stat out, hook the housing back up without the t-stat, start the engine and go see if the coolant is immediately flowing. If it is, you're t-stat is not working for some reason. If its NOT immediatekly flowing then you have a 1 in a million sheared water pump shaft and your water pump is gone. Big top end pulls is where that would happen. It may have locked up and caused the belt to go, then freed up again. Or a rag is in there somewhere blocking something (j/k).
But there is no reason, other than a sheared shaft on the pump, where the coolant will not flow with the t-stat out.
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But there is no reason, other than a sheared shaft on the pump, where the coolant will not flow with the t-stat out.
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it seems like a water pump problem to me, im pretty sure the rpms were up there when you were at that rate of speed and when the belt broke it was an instant shock to the pump. remove your pump and open the rear plate to inspect the internal
Is it possible to remove the tstat from the housing? I have an aftermarket tstat and it looks to be one whole unit. I think I still have the stocker so ill see what I can do with that. I will try pulling the pump next. If I have to get a new pump, will a stock replacement do just fine with what I have done? I was looking on scoggin-dickey and they have an l92 waterpump. Will that work with my setup?
Is it possible to remove the tstat from the housing? I have an aftermarket tstat and it looks to be one whole unit. I think I still have the stocker so ill see what I can do with that. I will try pulling the pump next. If I have to get a new pump, will a stock replacement do just fine with what I have done? I was looking on scoggin-dickey and they have an l92 waterpump. Will that work with my setup?
Water pumps are hit and miss man. I still have my 12 year old factory original, its lived through my stock engine, then the past 8 years in my 427ci, its still fine. You can get a higher dollar one or just a factory reman.
I'll tell ya this too, if you're gonna be doing high speed runs, the stock belt tensioner is a weak point, especially for modded engines. It bounces, and bouncing throws belts. You need to get the Katech fixed tensioner. It also guarantees your serpentine belt will literally last 5-10 years. If they don't bounce they hardly wear. Bouncing causes belt stretch, thats what kills them.
My belt is 8 years old and still looks 100% new and has not strecthed one tiny bit, my Katech went on in 2002 and its set in the same exact position the whole time...same belt.
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Joined: Aug 2007
Posts: 24,241
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From: Turnin' Wrenches Infractions: 005
Also, I have heard the hoses can collapse on the inside and still look fairly normal on the outside. I would pull both completely off and inspect that they arent caved in on the inside.