Replacement exhaust manifolds - OEM, Aftermarket, or ???

[Struc]

I have a crack in one of my 1988 4.3l exhaust manifolds. No idea on the inside, but it weeps water outside.

Looking for advice on replacement brands. I see there are a few, including Aluminum ones.

It doesn't seem that the Mercruiser 99746A17 manifolds are all that much more than aftermarket, so is there any reason not to use OEM?

How do all these aftermarket companies stay in business only charging $20 less? Am I missing something?

Would love to get away with just replacing the cracked one, but should the whole 2x manifold and 2x riser be done as a preventative step? I *really* don't want to spend $900+ on a boat I just bought for $1675 (although I realize it's worth more than that).

Thanks for any advice / thoughts.

 

[Fishermark]

Re: Replacement exhaust manifolds - OEM, Aftermarket, or ???

I am sure most will suggest replacing the set. Do a search here on iboats, but to be honest, I've had good luck and great prices from this site as well. Here's a whole set for under $500.

 

[Struc]

Re: Replacement exhaust manifolds - OEM, Aftermarket, or ???

Thanks for the link - that does seem a lot more reasonable. Have you used these manifolds before? I don't want to spend $500 on them only to have to replace them in another 3 years.

Any other advice out there?

 

[Fishermark]

Re: Replacement exhaust manifolds - OEM, Aftermarket, or ???

I have ordered a manifold set from them before - this was for a straight six. I called them in advance and spoke with them to make sure of the brand. I encourage you to do the same. The manifold they had for my application was made by Osco and I am pleased with the quality.