Exhaust manifold crack...repair??

[SHOOTER72]

I have an 84 Mercruiser GM V6 3.8 L 185hp.....today I found a big ol crack in the right side manifold and unfourtunaely its cracked all the way thru....

my question is....is there any repair that can be done to this before i just go out and spend $200 on a replacement kit????....maybe weld it?...maybe some sort of liquid metal or liquid weld or some other sort of high temp sealant??...or maybe i dont know what the hell im talking about.....but thats why im asking...

its probably a good 6 inches or so and water was whizzing out of it when i started it in the driveway today...

 

[Don S]

Re: Exhaust manifold crack...repair??

Obviously wasn't winterized, so I would be wondering if the inner part of that manifold is also cracked. If it is, you will have water in your cylinders when you shut it down. The same thing probably happened to the other manifold. And wouldn't surprise me a bit if the block isn't cracked too. Maybe inside. Have you checked the oil to see if it's milky and overful?

 

[fishmen111]

Re: Exhaust manifold crack...repair??

I fear that crack is just the first sign of the overall condition of the manifold(s). I would replace both of them

 

[SHOOTER72]

Re: Exhaust manifold crack...repair??

Obviously wasn't winterized, so I would be wondering if the inner part of that manifold is also cracked. If it is, you will have water in your cylinders when you shut it down. The same thing probably happened to the other manifold. And wouldn't surprise me a bit if the block isn't cracked too. Maybe inside. Have you checked the oil to see if it's milky and overful?

it actually was winterized and the water was drained....thats what is kind of weird.....even if it wasnt totally drained....wouldnt it have to be full to freeze and expand to crack?.....anyways, it was winterized and rv antifreeze was put into it......the oil was changed with mercruiser synthetic before i winterized and is nice and clean still...the other manifold is in good shape, no signs of cracking

 

[Don S]

Re: Exhaust manifold crack...repair??

Should have asked if it was PROPERLY winterized. There are lots of posts here about attempts to winterize by DIYer that turn into broken manifolds and blocks every year around the time.
How was the RV antifreeze put into it? That's the question.

 

[SHOOTER72]

Re: Exhaust manifold crack...repair??

hmmm...thats a good question.....i was helping a friend of mine while he was winterizing my boat and when he put it in i actually wasnt there....but i do remember taking the thermostat housing off and see the antifreeze.....maybe thru there??....unfortunately im not sure.......but, the question at hand is....is there any repair i can do?? or try before going out and buying new one or both maybe

 

[JCF350]

Re: Exhaust manifold crack...repair??

Nope. And buy both sides, manifolds and elbows.

 

[Coors]

Re: Exhaust manifold crack...repair??

hmmm...thats a good question.....i was helping a friend of mine while he was winterizing my boat and when he put it in i actually wasnt there....but i do remember taking the thermostat housing off and see the antifreeze.....maybe thru there??....unfortunately im not sure.......but, the question at hand is....is there any repair i can do?? or try before going out and buying new one or both maybe

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