When to change exhaust manifolds
 

I have 420 HP's with 600 hours. I wanted to freshen them up and was wondering what I should have done to them to get another 600 hours out of them? Also, when do you know its time to change the exhaust manifolds? I have Gil exhaust and I see some slight corrosion but wanted to prevent the problem of getting any water leaking in the engine. What should I do? Are manifolds the weakest link to potential problems?

Re: When to change exhaust manifolds
 

How old are the manifolds? Salt water or fresh?

Re: When to change exhaust manifolds
 

you should defenitly pull the elbows and change the gaskets. While you have them off inpect the surfaces, if there is pitting and corrosion then the manifolds and elbows need to be changed.

Re: When to change exhaust manifolds
 

With 600 hours of salt water use, they have more than out-lived their usefull lifespan!! Spring for some new ones this winter....before it's too late. :D