exhaust/intake manifold ? 3.0 merc (gm)

[elkhunter338]

Since on a 3.0 manifold it is the intake and exhaust. When the manifold or elbow goes bad from corrosion does it normally fail so the water drains into the engine?
Or do they normally fail with an external leak first?
Is there anyway to determine when an elbow or manifold is near the end of it's life?

I run 2-3 weeks a year in salt water, flush manifold every time I remove the boat from the water. The manifold was new 6 years ago because the old one cracked from the previous owner. So I replaced the manifold and reused the elbow since it looked ok.
I am not having anytrouble at this time.

 

[Bondo]

Re: exhaust/intake manifold ? 3.0 merc (gm)

Is there anyway to determine when an elbow or manifold is near the end of it's life?

Ayuh,... Ya, they tend to dump water into the motor 1st, then leak to the outside...
Ya have to pull the riser off the manifold, CLEAN the gasket surfaces, 'n inspect 'em...

I rather doubt yer's are goin' Bad, at yer saltwater use rate...