rock_doctor wrote:

Hi all,

How easy is it to convert a boat from an OMC Cobra stern drive to a
Mercruiser (i.e. can it be done and not have it leak). The local boat yard
says it can't be done because all of the holes in the transom are in the
wrong place and it will eventually start to leak. Of course they also told
me it would cost me ~$500 to winterize the boat... The current set-up is an
'86 Cobra 260 (350 Chevy) and want to convert to one of Merc's 6-cyl diesel
units. It is in an 1986 230 Chris Craft speed boat. The boat is used
primarily for low speed cruising so the (low RPM) diesel is not a problem we
are looking for dependability over time rather then performance.



When OMC first rolled out the Cobra drive, one of the selling points was
that the transom cutout was identical with Mercruiser, thereby
facilitating an easy conversion in the hopes that OMC might take a
larger bite out of Mercruiser's dominant market share.

As far as I know, they are the same. Of course you can probably find out
for sure by looking up parts and doing a comparison. Or asking an
impartial mechanic that you trust.


Dave