Engine Rebuild or Replace???

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Charlie

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While driving around Saturday, noticed a lot of white smoke coming out of the tailpipes. Stopped as soon as I could.
Raised hood and could not see anything visible of course. Started up again and smoke continued to come out. Had it towed to my service garage. Going to have it evaluated on Monday. I am guessing piston oil rings on one or more pistons. Thought possibly intake manifold gasket but unsure if that would cause the white smoke out the tailpipes? It has original engine.

If it is engine not sure if I want to rebuild or just get a crate engine.

Any suggestions
 

Craig 85

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Could be a blown head gasket. Did you check the dip stick? If the oil is milky, that could be the cause.

I would rather get my engine built local than get a crate engine, but in my case I ended going with a GM rebuild as the block that was in my truck was from the mid 70's, but had peanut port heads and an unknown history. GM had a 3 year/100K warranty on my new motor.
 

Charlie

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Could be a blown head gasket. Did you check the dip stick? If the oil is milky, that could be the cause.

I would rather get my engine built local than get a crate engine, but in my case I ended going with a GM rebuild as the block that was in my truck was from the mid 70's, but had peanut port heads and an unknown history. GM had a 3 year/100K warranty on my new motor.

Head gasket was a thought too. Forgot to put that in 1st post. I did check dipstick and it showed plenty of oil. Did not appear to be light brown as when it has coolant in it. Going by shop today to check out more. It was blowing out a lot of smoke.
 

nabeshin

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Could be one of the intake manifold gaskets. In stock form, there are coolant passages through it right next to the intake ports.

White smoke is coolant, blue smoke is oil, and black smoke is excess gas.

What does the radiator level look like? You should be low on coolant if you had this much smoke and none in the oil.


If it is just one of these gaskets, I'd just replace that instead of an entirely new engine.
 

Charlie

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Went back to check on truck. Oil looks good and full. Coolant level still full. If it definitely is head gasket, I may have stopped it in time before oil and coolant was affected very much if not any at all. Will maybe find out tomorrow what shop guys decide.
I did notice a little smoke coming from right rear of the right side head when I first looked. It was just enough to notice.
 

jjester6000

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Went back to check on truck. Oil looks good and full. Coolant level still full. If it definitely is head gasket, I may have stopped it in time before oil and coolant was affected very much if not any at all. Will maybe find out tomorrow what shop guys decide.
I did notice a little smoke coming from right rear of the right side head when I first looked. It was just enough to notice.

I'd pull the heads off before you decide (dissadembly is usually easier than assembly if you have an air ratchet) and take a look at the general condition of the engine.

This gives you the added bonus of not having to commit to either option (you could just replace the gaskets and stick it back together if you want).
 

Salty Crusty

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White is generally steam but can be trans fluid. Do you have a TH350?
 

Charlie

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White is generally steam but can be trans fluid. Do you have a TH350?

Yes it was white smoke. Thought it may be steam but did not dissipate quickly as steam does. I do have a TH350 that was rebuilt last November.
 

legopnuematic

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I have seen vaccuum modulator diaphrams go out and then start sucking trans fluid into the intake via the vacuum line.
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Joe Smo

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Rebuild from the bottom up, well worth it. Find you local engine shop to rebuild or do it yourself if you can, or find an 88 to 98 5.9L 12 valve Cummins and drop it in
 

80BrownK10

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While driving around Saturday, noticed a lot of white smoke coming out of the tailpipes. Stopped as soon as I could.
Raised hood and could not see anything visible of course. Started up again and smoke continued to come out. Had it towed to my service garage. Going to have it evaluated on Monday. I am guessing piston oil rings on one or more pistons. Thought possibly intake manifold gasket but unsure if that would cause the white smoke out the tailpipes? It has original engine.

If it is engine not sure if I want to rebuild or just get a crate engine.

Any suggestions
Blown head gasket if smoke was white?
 

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