TOPIC: '67 80hp transplant

Sooooo, I have this '67 80hp.....................isn't that how these usually start? lol Anyway I do have the '67 80hp and I'd like to replace the '59 Fat Fifty with this motor but here's the conundrum, do I make four new holes through the transom or transplant it inside the Fatty housing.

This is a shot of the transom before I put the Fatty back on. You can see the two holes for the lower part of the motor mount. The upper is the "C" clamp style twist in clamp. If I use the original mount for the '67 I have to make two new hole 2" down from the top of the transom about 10" wide and another two about 8" wider than the lower existing holes. I'm not liking the idea of making more holes in the transom but it would be necessary to mount this motor.

If I go this route I would use the '61 housing, thus looking more period specific to the boat (1960 Wagemaker). The only thing to do would be to still use the junction box and just pass the wiring harness through it so it looked like the '61. "67 didn't need the rectifiers in the junction box since everything was self-contained within the motor housing.

The other possibility would be to use the Fat Fifty housing and not have to make new holes in the transom but would the twist clamp top clamps and lower transom bolts be enough to hold her on the transom. Plus, how do I make the wiring harness work with the Fatty housing since it has a plug in style wiring harness to the lower cowl and the '67 comes through a hole in the lower housing. I don't want to bugger up Fatty lower cowl or the wiring harness in case I want to switch back in later years. Of course anyone who knows these motors will know it's not a '59 when they look at the lower unit since it's a selectric, plus the controls will give it away.

Maybe the 80hp in the '61 housing is the way to go, just not too sure about more holes. i know I should be able to just fill the old ones with silicone or just keep the bolts in with silicone around them and a fender washer with rubber gasket on the outside and inside.

Thoughts anyone?

Bob

That's a tough decision Bob, I know making new holes in the transom is a hard thing to do. It would be cool to use the upper and lower cowlings off the Fat Fifty (if they could be made to fit and you wanted to maintain the "period correct" look), but I would think you'd want to use the beefier transom bracket and lower unit off the 80 hp wouldn't you?

If you soak some dowel rod in epoxy/resin and drive them into the old holes, they could be made almost invisible with a little work, right? Besides, they would likely be under the newer transom mount since I believe it's a little wider? Just speculation on my part, I don't know the specifics of these older motors. Maybe one of the OMC guru's can confirm, but I'd be inclined to go that route.

Could you fill the old holes on the transom with some wooden dowels and stain and poly them to match and use the better bracket? jim

Agree on the dowel route. That way it will look alot cleaner and you should be able to hide most of them with the newer mount. There's a older person who has a nice Thompson on a lake I go to and last year he repowered it with a new honda and even though it did look different he said the motor really was alot nicer to operate and cheaper to run, so he was really happy with it even if it didn't look original.

Sorry Mark, Blind in one eye,can't see out of the other. Didn't catch it in your post

Mark, I would be using the '67's lower, if I went the Fat Fifty housing route it would only be the cowlings changing, nothing else.

The dowels are a good idea but I would have to drill them back out if I wanted to mount the Fat Fifty back on there. There are only two lower holes, the top of the mount is the threaded clamp style. The other thing is those lower holes won't be hidden since they're only about 6" apart and the lower holes on the '67 mount are 8" apart. That's why I was thinking of just keeping the old bolt, with silicone and gasketed washers in place so I wouldn't have to drill out filled holes if I wanted to revert.

Bob

If the old holes will be covered with the larger bracket why not just plug them with a rubber cork or similar. That way if you do change back you can just push them out.