4 stroke conversion & reverse?

[krp]

I have a 1990 Marathon with the 3PG 2 stroke engine. I would like to replace the 3PG with a 4 stroke engine. But, to my knowledge, 4 strokes don't run in reverse like 2 stroke engines do. Is there a way to make the 4 stroke run in reverse?

[Ron Benedict]

Nope.

[krp]

Thanks. Didn't think so. I guess a better way to phrase the question is: Will I have to get a gas cart differential + axle with reverse to use a 4 stroke motor?

Since posting the question I looked at an '09 thread about a big block, 4 stroke conversion where the guy had to build a new engine cradle and mounted a 4 stroke diff. & axle. He used an EZGo shift cable part #72721g01. The cable cost $170 ten years ago. Who knows how much now. Besides, I can't afford such a build. I'm in the Harbor Freight Predator engine price range, i.e., around $200 for the engine. Any ideas?

[PaintMaker329]

Originally Posted by krp

I have a 1990 Marathon with the 3PG 2 stroke engine. I would like to replace the 3PG with a 4 stroke engine. But, to my knowledge, 4 strokes don't run in reverse like 2 stroke engines do. Is there a way to make the 4 stroke run in reverse?

Yes, you can swap out rear ends with a 4 stroke trans

[krp]

Thank you thank you... I'll start searching for a pre-owned, slightly used, even very used but repairable rear end. It might even have a shift mechanism. There must be a cart junkyard somewhere in the state of Flawda. If not, I'm sure somebody has one they want to get rid of. I'll keep you posted.

[PaintMaker329]

Many cart salvage yards around

[dirtyyoda77]

why not just rebuild the 2 stroke probably cheaper than everything else

[PaintMaker329]

Originally Posted by dirtyyoda77

why not just rebuild the 2 stroke probably cheaper than everything else

What fun is that?

[trig123]

I second the rebuild. Those 3pgs' are sort of rare. I like them. Don't mess up a good cart with the upgraded engine. Cheap rebuild :)

[krp]

Rare 3PG? Make me an offer. I've already rebuilt the carb, down to making gaskets (to stop the leaking gas) for one of those cheap Mikuni knockoffs. I ended up using bits of the original carb, e.g., jets. Then I replaced the fuel pump with new lines and filters. Oh, and electrical stuff too numerous and frustrating to mention. That's all in addition to the regular tune up stuff. Then there's the 2 stroke noise which now sounds like piston slap. I've done mufflers (no OEM here, not for approx. $600.), flexible stainless pipe, a cool exhaust tip and replacing all the sound deadening material. Enough. This ain't no cool-sounding F1 Moto GP race bike. I've also replaced belts, clutch bolts that keep working themselves loose despite Locktite, etc. Add to that, pushing it several times when it stalled and wouldn't restart.

I'm a motor head from the 1960s. I worked as a mechanic. I've rebuilt engines. So, yes, I have the tools and knowledge to rebuild the 3PG. I could even "slap" in a new piston. But as a wise man once said, "Where's the fun in that?" Maybe what it boils down to is that I'm a retired anthropology (really poor) professor, thus my wordiness, with chronic, severe back pain and other ailments that accompany being 73 years old. My neighbor is a mechanic with a garage. All I have to do is something I like, which is search junk/scrap yards. It boils down to old age and poverty. For 3PG lovers I'll make an offer you can't refuse. Realistically, I'll probably diagnose the latest non-starting problem, again, and fix it myself with a few Maybe it's time for a new reed valve & gaskets? In the meantime...back to the scrap yard. But I welcome more suggestions. Thanks everybody.