Exhaust manifolds

Honestly scofflaw is much more knowledgeable than me when it comes to boats.

That said, you will definitely need all new gaskets for the manifolds and go ahead and pick up some bolts. Make sure to spray the old bolts on the manifolds with penetrating lube oil 24 hours before trying to turn them, or you’re liable to have some break. Getting a broken one out can be a huge pain. While you’re at it, I’d replace both water pumps as well, but that’s just a personal preference. At least do the impellers if you’re not sure when they were last replaced. While you have the pumps open you can see how badly the housing is scored. Or not scored. I replace my pumps every two years ..impellers every season.

Barlow1016 said:

M Prod, What else can you councel me on to purchase while I am purchasing these OEM exhaust manifolds and risers? Probably purchase all new hardware? Also what about any thing else that comes to mind? Thanks for your time man

Click to expand...

See if you can find a kit that includes the gaskets and new bolts. I used to be able to find them for the small blocks when I had my old boat. If you can’t get a kit that includes everything, then getting new bolts is still a good idea.

Get some grade 8's, will make removal in the future easier. Stainless in that size can't handle the 30#'s

Its only ceramic coated on OUTSIDE. By the time the outside rust the inside would be shot. You get a little surface rust in a few easy to reach spots that you can quickly spray with some engine paint each season. Been using them for years on salt water boat. Someone on here recommended using the threaded rod trick which you cut a couple of pieces of threaded rod long enough that you can unscrew it with your hand while the manifold is on. You screw them in and slide your gasket on then slide manifold on . The threaded rod holds the weight of manifold on while you get the other bolts in or out. Not sure if yours is the same or if they where removed there is a heat shield that is on the front left by alternator that has smaller nuts holding it onto the bolts of the first to manifold bolts. I THINK they where 1/2" nuts and the manifold bolts where 9/16.