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Discussion Starter #1
I took my 27' ultra light 5th wheel for a 3 hour drive to go camping today and once I hit the free way doing average 100 kmh my egt were around 1100 on average. It would spike to about 1200 or more on hills. Then I would let off. I kept going keeping egt at 1000 and above because that's the coolest it would run on hwy. I stopped and pulled over once the low coolant light came on. Worried as hell I checked under the hood and resevoir was near empty. Looking for where it went I noticed the whole passenger side of truck was covered in coolant along with trailer. I pulled inner fender to check rad hoses and engine. But no leak. Finally I think I figured that it came from coolant reservoir overflow tube. So was my coolant so hot that it was boiling? I noticed moisture build up on inside of coolant reservoir. Help me guys I'm sitting at a camp ground frustrated and wondering what to do.
 

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Head gaskets must be bad. Cylinder pressures escaped into the cooling system pushing your coolant out. Thats my guess.
 

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Does sounds like the head gaskets are bad-- getting to be a common problem on the LLY. They changed the design on the LBZ and they seem to be better.
 

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I had a similar problem one time when towing and it was my headgaskets.

In the morning with a cold engine, try to squeeze the upper rad hose. If it is still hard, it is pressurized and your head gaskets are most likely gone.
 

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Does sounds like the head gaskets are bad-- getting to be a common problem on the LLY. They changed the design on the LBZ and they seem to be better.
and he looks as if he has done everything except additional coling system capacity to prevent this.... any definative cause of the head gaskets?
 

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Discussion Starter #6
This morning I squeezed my rad hose and I could callapse it together. Also I refilled the reservoir and turned engine on with cap off the resevoir. I saw no bubbles at all.
 

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headgaskets man. same thing happened to my old subaru and my old LLY
 

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There is a small cover on the back of the motor by where the head meets the block. Sometimes the gasket will go bad causing major coolant loss. I would check that first before assuming the head gaskets are bad.
 

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There is a small cover on the back of the motor by where the head meets the block. Sometimes the gasket will go bad causing major coolant loss. I would check that first before assuming the head gaskets are bad.
ive replaced that gasket.... its in a bitch of a spot....
 

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ive replaced that gasket.... its in a bitch of a spot....
Sure is. Good news is its only a few bucks to fix if that is the problem.
 

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get a compression test done. As soon as they did that, it was confirmed that my head gaskets were gone.
 

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Discussion Starter #12
Hmm. Ya I'll get a compression test done. Once again this morning after having it up to full temp the day before I squeezed upper hose and it collapsed together. I also checked for bubbles in resevoir and there is none. Still sound like gaskets. All that happened was the overflow tube oiled out so coolant when engine was working it's bag off. I was towing with a pretty hot tune (90hp) which I know I shouldn't be.
 

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The compression test, nor the coolant pressure test, does not always show a bad gasket.

I would refill the reservoir and burp the system of air, [small bolt at the thermostst housings] and just drive it. Monitor it for leaks, or a hard hose- in the AM.
 

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Discussion Starter #14
so all i do is loosen that bolt on housing and it will bleed all the air out of cooling system?
 

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ive replaced that gasket.... its in a bitch of a spot....
Sure is. Good news is its only a few bucks to fix if that is the problem.
I know first hand it is :eek:

Have you eliminated the simple stuff....like the cap on the overflow tank?

I'd do that before throwing expensive parts at it.
 
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