1981 EZGO Marathon - Engine Power Loss


New Member
My 81 EZGO Marathon has the 2pg engine that has a power loss. The engine runs fairly well when cold but seems to lose power once it heats up and is put under load. On a slight incline the engine slows down and would eventually completely lose power over a long enough distance. I recently performed a compression test and the results were 125-130 PSI. I have been troubleshooting this for a few months with no real solution. Looking for some suggestions aside from the new parts installed (listed below). Is it normal for the 2pg engine to get, what seems like, very hot? After a 10 minute ride the engine is ticking and the exhaust will boil water. What are our thoughts on eliminating the air box and going with an open element air filter? Thank you in advance!

Parts installed recently:

- New muffler
- New fuel pump
- New air filter (still in stock air box)
- New plug, wire, and ignition coil
- New battery
- New drive belt
- New carburetor
- New fuel filter


Cartaholic - V.I.P.
I would see what color the spark plug is, sounds like it may be running lean. if the plug is light gray or white then there is a fuel problem, many aftermarket carbs are no good:twocents:
Pre mixing the gas n oil is best in the older carts, disconnecting the oil injection system is what many do.


New Member
Thanks for the reply Nubs. I know the previous owner replaced the carb, so its possible that he bought a cheap one and it should be replaced. Any suggestions on a good carb manufacturer to replace it with? Also, any thoughts on modifying the air intake to open element or something better than the canister? It doesnt seem like the cart is getting enough air through that small canister opeing?



New Member
Thanks for the reply! So I purchased this carburetor and also a new air filter and installed them this morning. The cart instantly ran better cold out of the garage, but as the ride goes on the motor heats up rapidly and causes the engine to lose power, significantly. This has always been an issue, so I don’t think the new carb has anything to do with it. Once the cart sits and cools down it runs great again until it reaches the high temperature again. I am mixing fuel 128:1 and the air filter is brand new. What causes the engine to heat up so much? A drop of water boils instantly on the engine and exhaust after the heat up.