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Discussion Starter #1

5.7 block and heads sent to machine shop.
Rebuild kit ordered specifically for this engine and
its bore. Reason for rebuild was a blowed head
gasket that locked the motor up. Upon cranking my
newly rebuilt engine which has only 10 miles on it.
Once it warms up there is white smoke which isn't
bad unless I rev the motor up. Checked all fluids
everything is good. Drives like a new truck sounds
great. Just concerned about this white smoke.
Could it be that the all these new parts aren't broke
in yet? Asking for help. Just for the info I thought
cause of the blowed head gasket that I might have
coolant build up in my catalytic converter. So we
cut it out. Still smokes. Again, just a little when
idling but clouds when accelerating. My coolant level hasn't moved.
 

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White smoke is usually coolant. Pull spark plugs to see if one or more has a white tint/deposit on it. If so I would do a pressure test on the cooling system to see if there is a cylinder leak somewhere that gets worse when heated.
 

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Discussion Starter #3
Pulling the spark plugs is my next step to try. But the only thing that has me stumped is there is no coolant level drop or the smell of coolant coming from the exhaust. I believe that pulling the spark plugs will tell me what I need to know. However if I pull the plugs and see no take signs of anything should I then feel comfortable to say the smoke maybe because it's not broke in yet?
 

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Engine rebuilds should not smoke during the break in period; maybe a little oil smoke, but just a little grey/black smoke.
White smoke of any amount is water.
 

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^^^X3, who torqued the heads down? Did you put some sealant (like Permatex the right stuff) on the intake manifold gaskets where the water jacket ports are? Did the machine shop magnaflux (Magnetic Particle Testing) both the block and heads looking for cracks? Did they check/mill the decks and heads for flatness?
 

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Discussion Starter #6
Yes everything was magnafluxed I actually had to go buy a another head because one of the originals were cracked. Everything torqued to specs everything from bottom to the top was lubed. I'm not losing any coolant oil looks great. No blow by. I'm definitely going to pull each spark plug to see what they look like. Hopefully that will give me a sign of what's going on. If they are clean I'm stumped.
 

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Compression check might turn up something.
 
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