Blown head gasket questions

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Catfish26kc

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Gentlemen, new to this forum, never posted anything. Kinda familiar with 80's gm trucks. I'm 99% sure I've got a blown head gasket. Symptoms, rough running white smoke out of 1 tailpipe. Small coolant leak I haven't located due to 2° weather outside....
 

RustyPile

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When the hot exhaust contacts the cold air, condensate will form. that's the white cloud seen at the tail pipes of automobiles.. That's not to say that's the cause of the white smoke you're seeing..

The symptoms you've described are not all conclusive for a blown head gasket. Here's one step in diagnosing your problem.. Rent or otherwise, obtain a cooling system pressure tester.. Some parts stores will loan certain tools. Remove all the spark plugs. Remove the radiator cap and install the pressure tester.. Pump up the system and wait about 5 minutes.. While you're waiting, look around for a coolant leak. With the spark plugs still removed, crank the engine over and watch for moisture spraying out the spark plug holes.. If moisture blows out any of the holes, that means coolant has found its way into the combustion chambers.. Could be a gastet has let loose, also could be a crack on the head. Head removal and inspection are the only way to determine which.
 

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Is it overheating? Does the heater work normally?
 

Catfish26kc

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Not overheating as of yet. And the heater works great.
 

Catfish26kc

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It runs smooth at initial start up and both tailpipes blow the usual winter white. But after warm up the passenger side stops the white and the driver side really kicks out the white. No smell of coolant just a heavy fume... and it idles rough.... carb issues possibly?
 

GTX63

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No sweet smell from the exhaust? Ok, remove the radiator cap and warm the engine. Excessive bubbling in the coolant is a symptom of exhaust gas escaping into the system.
You can also check for CO in the fluid using a chemical that will turn blue if exhaust gas is present.
A leaking headgasket should leave fluid in the cylinder after shutdown, meaning the engine would likely be running rough at start up until the fluid has dissipated and until pressure pushes fluid into the cylinder again. You can also pull the plugs for a quick read.
 

RustyPile

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It runs smooth at initial start up and both tailpipes blow the usual winter white. But after warm up the passenger side stops the white and the driver side really kicks out the white. No smell of coolant just a heavy fume... and it idles rough.... carb issues possibly?
The smoke sounds like normal winter "stuff".. When's the last time you did a tune up??
 

Ricko1966

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No overheating and good heater,I'd be looking somewhere other than headgasket first.
 
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Bextreme04

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Well if you did all that,its gotta be a headgasket.
Or a cracked head, or a bad intake manifold gasket can also cause this if it blows between the coolant passage and the runner for #1 or #7 instead of into the valley.
 

Ricko1966

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Or a cracked head, or a bad intake manifold gasket can also cause this if it blows between the coolant passage and the runner for #1 or #7 instead of into the valley.
I hope you noticed the sarcasm. Lots of things to check before condemning the headgasket
 

Bextreme04

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I hope you noticed the sarcasm. Lots of things to check before condemning the headgasket
I didn't... which is why I was putting that on there. He was replying to rustypiles question about when the last time he did a tuneup was.

Got to be careful with sarcastic comments like that, especially with a new member that obviously isn't all that familiar with these things and could take a comment like that and run with it. Maybe an emoji or something to let us slow folks know that you mean the opposite of what you are saying ;)
 

Ricko1966

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I didn't... which is why I was putting that on there. He was replying to rustypiles question about when the last time he did a tuneup was.

Got to be careful with sarcastic comments like that, especially with a new member that obviously isn't all that familiar with these things and could take a comment like that and run with it. Maybe an emoji or something to let us slow folks know that you mean the opposite of what you are saying ;)
You are correct sir. Sorry . And thank you.
 

Chuckd84

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If the exhaust is a true dual setup, and has cats, would a plugged or restrictive cat cause a exhaust temperature drop? That will make the white steam/condensation. I might be overthinking this one lol
 

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