Why are my valves rusty?

[Hogger]

Well, water of course. But do you think maybe the gasket is leaking from the exhaust manifold? Or maybe a bad head gasket?
The port side is clean, but all 3 on the starboard side are rusty, and had a little water in them.

How should I fix this?

 

[HT32BSX115]

Re: Why are my valves rusty?

Well, water of course. But do you think maybe the gasket is leaking from the exhaust manifold? Or maybe a bad head gasket?

Howdy,

Engine make, model, year?



How old are your exhaust manifolds and risers? When did you last pull the risers and inspect? (ever?).......SALT or fresh? (I guess you're fresh in the Columbia!!!)

It's usually NOT a head gasket... (it can be though....but usually NOT)


Regards,


Rick

 

[Hogger]

Re: Why are my valves rusty?

Oh ya. 1993 Mercruiser 4.3LX.
I just got the boat a couple months ago. Previous owner said they didn't winterize it one year and cracked the block. So they replaced the block, but it looks like they used all the other parts because on the bottom of the exhaust manifolds there is JB Weld.
Based on the history I have, it hasn't seen any saltwater.

 

[Philster]

Re: Why are my valves rusty?

Start with the most likely suspects: Exhaust components.

That's where'd I place my bet.

 

[Bondo]

Re: Why are my valves rusty?

but it looks like they used all the other parts because on the bottom of the exhaust manifolds there is JB Weld.

Ayuh,.... Sounds like the repair didn't work so well.... Time for New 1s...

 

[bruceb58]

Re: Why are my valves rusty?

Ayuh,.... Sounds like the repair didn't work so well.... Time for New 1s...

It may have fixed the crack on the outside. Sounds like there is a crack on the inside as well.

 

[wca_tim]

Re: Why are my valves rusty?

It may have fixed the crack on the outside. Sounds like there is a crack on the inside as well.

what he said.. I bought a boat from a guy that complained that the engine kept blowing and puking head gaskets... he had brazed a leak in a cracked exhaust manifold on the outside... It leaked on the inside... spend the coin to get a new set of exhaust manifolds and risers... or I would anyhow...