Inliners International Forums General Discussion Engines marine swap: 250 to 292

Hi! I have a GM 250 inline six marine engine in my boat. I want to replace it with a 292 that I found in an old Gleaner combine. Will this work if I use the marine carb and distributor from the 250? Will I have to buy a marine cam for the 292, or should I use the one that's in it? Also, do marine engines use specially balanced flywheels, cranks, and harmonic blalncers? Thanks for your help!

I don't know any of your questions.. Sorry .... but just wanted to say do not use a carb that is not for marine! First that are jetted differently for constant load and most inportant they usually are designed so that if the float stuck the fuel goes down the throat of the carb and not in your boat!... May make it run rich.. If not... Kboom!

Clyde

The 292 will accept the marine int|carb for the 250,distributor fits as well.Mercruiser offered a marine version of the 292 for a few years.The carb should be a marine version of a rochester 2 bbl.

Several years ago I swapped 250 merc marine motor for a pass/ truck motor in a boat. The Pass/truck block casting was slightly different on the frt. where the marine motor mount bolts in place. I had to fabricate an "ear"(1/4"plate)that bolted to the block and to the motor mount.Everything else from the marine motor bolt on with no problems.I don't if your aplication is the same but this worked for me. Also take note the the 292 motor is a little taller which might cause some clearance problems. Maybe this will help--Paul

The flywheels are not ballanced any differently but you might want to take note that all 292 flywheels after 1966 have 1/2" bolts in contrast to the 7/16" bolts on the 194, 230 and 250 CID motor. So if you want to use your 250 flywheel on a 292, you will probably have to have the flywheel drilled out to 1/2" bolt holes. The bolt circle spacing is the same so it's not a big deal. See page 26 of Inline Power Manual for details.

Paul wrote:
>>Several years ago I swapped 250 merc marine motor for a pass/ truck motor in a boat. The Pass/truck block casting was slightly different on the frt. where the marine motor mount bolts in place. I had to fabricate an "ear"(1/4"plate)that bolted to the block and to the motor mount.<<

I just wanted to point out that they used those blocks with the extra bolt holes in the front in trucks maybe cars too?)
I'd imagine the industrial engines were mounted same as a boat motor.
Are they rubber mounts in a Mercruiser or solid?
What holds the rear of the engine up?