Marathon rear differential

felber61

Okay gurus I finally got the old girl running good and the wife and friends (along with some spirits!) took it out for a trip down the road. Well they got 4-5 miles down the road and it quit on them. Now it's dark so I chase after with the truck and a tow rope and bring them back. The next day I go out and the drive belt is shelled and the clutch that attaches to the rear differential has about 3" of play in all directions. Cut the belt off and cart fires right up! I'm guessing rear differential went belly up. We never went over 10 mph on the way back. Those gals must've been putting it through the paces. I had to leave for work and haven't been back to town since. Can anyone give me a brief summary of how bad this could be? I know diddle about the rear ends in these carts and I'm hoping to repair back to stock. I'm deep enough into this cart now I hate to scrap it. 1987 ezgo 2pg, hei conversion, fresh top end, premixed. Thanks in advance!!

BGW

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felber61

Okay no takers? Does anyone know what kind of rear end it would have? I've rear different things like Dana and possibly ezgo but can't find a definitive answer.

StoveBolt

Wish someone here could help you, I know on 4 cycles the rearend has a forward and reverse and they
started with them in mid 90s and wouldn't work. So I'm guessing one for a 2 cycle if that's what you have.

1989Marathon

Not quite sure what "shelled" means, but it sounds like it was shredded.
See if the play is only with the clutch, or also the input shaft to the transaxle is moving around.

TomStark

I believe they are hypoid gears, which would be like gears in a regular RWD car. If this is the case, here is what I would do. First take off the driven clutch. I have the same cart as you, 87 Marathon, and just took my driven clutch. Remove the bolt in the center (after removing the cover, mine had no cover so...) There are washers on the bolt, observe the order of them so they go back on the same way. Mine had only a special formed washer with a single washer on top of that, (have no idea what it is supposed to look like, who knows what was done with mine before I bought it!)
Once that bolt is off, the driven clutch will slide off. I did have to pry gently with 2 screw drives, one on each side, between the diff and the clutch. Once that is off, there is a splined shaft. See if that splined shaft has play in it, it should not. If it wiggles around, then I would suspect the bearings are shot. If the bearings are shot, there is a chance that the gears are in trouble too. Does not mean that you can't still use those gears, but they may be noisy. Anyway, if there is play in that shaft, then you will have to pull the rear cover, pull the axles, and pull the diff apart to inspect all the parts and replace what needs to be replaced. If there is no play in that shaft, then you have the driven clutch off and can inspect it to see what is wrong there. Good luck, and feel free to contact me any time you wish. I have done many car rear ends, no carts, but this one should be pretty similar to a car.
Tom

1989Marathon

It does have a hypoid gear set. It is much stronger, but less efficient than a spiral bevel gear set. Unless the input shaft is loose, I doubt the gear set is damaged.

TomStark

My thinking is that if the pinion bearings are bad, it is wobbling, and in that case, the gears are not meeting at the correct angles, and the heel and toe of the teeth are being worn. Have seen it before when the pinion was too loose. My buddy's truck had that issue, had to put in new pinion bearings and crush sleeve. the ring and pinion gears looked pretty nasty, but we reused them and he put 30k miles on the truck before he sold it.
Tom