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Coolant issue....headgaskets?

98L36

New member
Temp gauge will climb to 210 and keep on climbing (fans on at this point) until it hits the red (260) then it will fall back down to 185 ish and then stay between 210 and 185 like it should until it's shut off, cooled down, and restarted.....then it starts all over.
I've checked it with a scan tool and it's not a bad temp sensor or gauge, scan tool says the same temps as gauge.

What's got me confused is that sometimes I can move coolant from the overflow bottle back into the radiator after everything is cooled down (by squeezing upper radiator hose then taking off radiator cap and covering the hole with hand then letting go of radiator hose.....doing that 10 or so times). After doing that the radiator will be filled with coolant, but the next time you check it after it's been warmed up and cooled down the radiator will be low on coolant.

I've been topping the radiator off with coolant by doing the above method, but I'm thinking that it should do this by itself.....shouldn't it??

Oh, and another thing, I heard a bubbling kinda sound coming from the engine one day and discovered that it was coming from the coolant overflow bottle.....it was bubbling air inside there. I'm assuming that's not normal......


So, what you guys think? Head gaskets or something else? :th_nervous:
 


brown coolant or whiteish milkshake oil is a good indicator of headgasket issues.


Or leaking LIM gaskets, which 99.9999% of the time this is the reason. That or a warped/cracked UIM.

If you suspect a HG, then do a compression leak down test. If all that checks out them time to join the LIM club :)
 
Forgot to mention these things earlier (which is my fault) but the intake gaskets were just done a week or so prior to this problem starting and the coolant system was flushed and re-filled and bled when it was being put back together.

Also, Bill, just to make it clear (not saying you're wrong) but I wasn't just hearing the bubbling, I could see it. Just took off the overflow bottle cap and I could visibly see the coolant bubbling in the bottle, that's what had me suspicious.

And, darkhorizons, I will have to go out and check the color of the oil/coolant. When the thing was torn apart for intake issues I also took out the coolant bottle and cleaned it out till the thing was spotless (it had some kinda brown looking stuff inside :th_nervous: ). So with a clean bottle and totally fresh coolant I will be dayumed if there is any color odd color to the coolant....:th_angry-pissed:
 


Likely you have air in teh system and the excess pushes into the bottom of the overflow. The bubbles rise.

You have a better chance of being struck by lightening than a bad head gasket. Those that thought they had HG problems and tore down, almost always found out it wasn't bad.
 
I have asplodeded a headgasket... Did take about twice the power what the average heavily modded car on here makes though...

Could be related to your lim situation, and the fact that you probably did not fill the coolant correctly after it was done.
 
I don't know why, but it's been running fine for about 2 weeks now and the temps are staying down, the radiator is staying full of coolant and the bubbling in the coolant overflow bottle has stopped.
All I know is that it ain't acting broke so I ain't gonna fix it.
 
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