OMC 6 hp piston interchange

[raglover]

I have a few basket case 6 hp’s I got in a group of motors. Most have scored pistons, piston rock and gouged cylinders. However, I have two good pistons, one has 2 rings, the other has 3.

The new PN is 386692 for all models. I am assuming it will make little difference in operation but want to ask.

As for my best block I am going to lightly hone to clean up light aluminum transfer and then install the two non original pistons with their original rings. New ones seem to be scarace and expensive. Am I destined to fail?

Amazing that I have 4 blocks and all are damaged in some way. Would just like to salvage one runner if possible

Thanks

Allen

[Mumbles]

Here’s the beauty of the 5.5 and 6 horse motors, all of the pistons will interchange thru the years. A ’54 three ringer can be used in a ’79 motor which had two rings and vice versa. Go ahead, mix them up, have fun! But use the appropriate connecting rod for the motor.

[raglover]

That is great news! Thanks for the reply.

[PugetSoundBoater]

That is very fortunate that both the 5.5 and 6 hp during that many years can use the same piston . The crank rod journal must be a different diameter, is why Mumbles said to use the rod from the motor, just swap the piston out. Is that correct? Cause the 5.5 have bushing type rod bearings, the later 6hp had needles correct?

"Some people want to know how a watch works, others just want to know what time it is"
Robbie Robertson

[fleetwin]

Yes, the original 5.5s used bushings on the large end of the rods, later model 5.5s and 6hps used needle bearings.

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