Obsolete OMC parts for inboard outboard

by joe stong
(Selbyville, De)

I just aquired a 1975 Cobia with a 250 chevy straight six and an original omc outdrive. I hasn't been run since 1998 but was always well maintained. I knew the previous owner. I took off the seized water pump and saw a lot of rust. I then did something i regret. I took off the end cap and riser elbow from the exhaust manifold. The salt water has eaten away a goog chucnk of both flanges and i know i'll never get a tight fit again.

I know of a couple of manifolds for close to $ 1,000.00 but was talking to a mechanic the other day and he suggested that i could get a mercruiser manifold and ell and pipe the exhaust out the transom. Cap the pipe from the bell housing and it should be fine. He also said it would be better for the lower unit because i'd be eliminating the extra heat from the motor into the lower unit. I'd like to eventually switch to a mercruiser out drive anyway but won't unless this one gived me some problems. Everything else on this unit seems to work fine, even the steering system. I have no problem working with the fiberglass so that would be easy.

Question:Does this alternate plan to pipe the exhaust through the transom and bypass the lower unit sound feasible?

Lastly: If that doesn't work does anyone know where i could get a used manifoldthe new massss