you have a blown head gasket

someone has removed the thermostat to keep your engine from building too much boost in the cooling system and keeping the ponies under control

it's stoopid to just "take it to the radiator shop" cause some dood on yt said to check for blockages

I'm sure your radiator cap is fine too.

when I blew...i mean discovered my melted hg it had no symptoms other than lots of pressure in cooling system and blowing out anything i put into it. no water in oil, oil in water, smoke out exhuast, ect

go get a compression tester son!

 

The mechanic said he's gotta pull the head. It it possible to put the head gasket backwards and it look right. I think its pushing exhaust into the water

 

The head gasket only goes on one way...

 

no, it will go on reversed. it is symmetrical, somewhat, in the long direction.
it will block oil and water passages if installed "up side down".

 

try flushing the system

 

Head gasket is bad mechanic just called. Sending head off to be checked...wonder what that's gonna cost

 

I'd guess around 800.

 

Damn. This $3000 truck is starting to get expensive

 

Ok, scratch my last post..It will only work one way.

 

If it is pushing exhaust into the water I would expect to see steemy smoke out of the exhaust pipe.

 

If it is pushing exhaust into the water then it would be forcing a lot of pressure into the cooling system, causing water to come out of the radiator. It would only steam out of the exhaust pipe if the water got into the cylinders.

 

I stand corrected.

 

i had a problem with it doing the idle up and down same as you it was the idle control senser soon as replaced it quit.

 

Pinch off the vacuum line to the brake booster. If that stops the idle issue then you probably have a vacuum leak in the brake booster.

 

I had a cracked head that would pressurize the cooling system, but had zero coolant entering into the cylinders. No steam out the tailpipe.


To the original poster, you have it at the shop, they've taken it apart and are doing the head gasket, you might as well spend 200 bucks, buy a metal-backed timing chain kit, and a performance cam and have them install the two when putting it back together. It's already apart anyways, there won't be any additional labor.