[dmorley]

Mercury used a one piece exhaust manifold on their 4.3 liter engines between 96-99. Are there any drawbacks to these?

[magster65]

I was looking at a boat that had that engine/manifold combo. I went to a local shop to query a friend, he said they crack occasionally. The boat had sold by the time I returned.

[dmorley]

I just found out a big limitation of the Mercury one piece exhaust manifolds: I can't install a full closed cooling system and had to settle for a half system and guess will replace the manifolds when they rust out at $575 a piece.