1990 Marathon Engine Questions

[jimfitzge]

I've got a 1990 Marathon with the 3PG 2 cycle engine. Had been running good and then started to run a little rough/cut out on power a from time to time. Now it won't start. Checked spark and have good spark. Carb is a year old so I put on a new fuel pump since I had a new one on hand. Cart is getting fuel as spark plug is wet after cranking and you can smell it getting gas when it cracks. Finally, when trying to start it, I notice where the crankcase meets the cylinder, I am getting bubbles and liquid (assuming gas) where that gasket is. Assuming this is what is causing it not to start??

Is it possible to pull to just cylinder off and replace that gasket while its in the cart or should I plan on pulling the engine and tearing it down/doing a rebuild? If so on rebuild, does everybody just order a new parts - ie jug, piston, ect or is it cheaper to go to machine shop?

[Timberwolflt]

I’ve been known to go both ways... if it was running pretty good before the leak developed... I might spend a couple hours and throw a new gasket in there and get right back in the road... if the motor was gettin really tired and gonna need a rebuild soon... I’d bite the bullet and just do it because other things tend to start failing

It ain’t too big a deal to pop that jug off right in place... basically pull the carburetor, exhaust and the plug wire... clean it good before you start tearing into it though so you don’t contaminate everything

[Dabble Inn]

X 2

[jimfitzge]

Thanks for the feedback. It had been running pretty good the last couple years I have owned it. What's the best place to order parts from for these Marathon carts?

[dirtyyoda77]

Most of the site sponsors should have a gasket and seal kit for you