1990 Marathon EZGO 3PG GAS Pours out of Carb!

Jim Dandy

Hello, I've spent literally days trying to diagnose my issue to which there are several others who've experienced the same and I've read many many posts with no solution.

Question One - are these after market fuel pumps all the same because they look the same all for under $20 with the exception of the one and only "Makuni" made in Japan and sells for $120 ??? Mine is the one without the third nipple for a vacuum hose.

I just replaced my cart with a brand new Carburator out of china. I actually bought two because they were so cheap. The issue Im having is that the cart seems flooded and wont start. I took off the air filter hose that connects the can to the carb and it had a lot of gas in the hose. I took the carb off and checked the needle and float. Seems fine! did a vacuum test and it checks out. I replaced it anyway with the second new carb and it too just pours gas out the throttle body into the airbox hose (accept the air box hose is removed for viewing) I also tested the float and needle valve and it too checks out. I replaced all the fuel lines, new gas cap, new fuel pump too. It still pours gas out. After replacing all of the above items the cart ran pretty darn good although it was running rich as it was smoking out of the exhaust pretty bad. I parked the cart and it sat for two days while I went online to figure out how to adjust the one and only adjustment screw to see if I could get the smoke cleared up. When I went to start the cart two days later It wouldn't start. I checked spark, all good. then I took the air filter off and discovered what I explained above, gas in the air hose.

All the folks I've seen with the problem- most pro's reply with the needle valve float theory which to me seems like the culprit too but that all checks out fine. Why is gas just running out of the carb??? could it be the fuel pump? I did pull the new one off and then took it apart and it was fairly dirty. I had also cleaned out my fuel tank during my mini tune up/overhaul so thinking that some dirt may have wrecked the fuel pump? when I pulled off the fuel pump i turned over the engine and fuel poured out of the "surge hole" or whatever the compression hole is called? that runs the fuel pump. Next I took off the carb altogether and turned over the engine. it eventually ran like a champ burning off all the fuel that was in the case? I then sprayed starting fluid a few times in the hole where the carb should be and the cart would run like a champ! BTW - this motor was brand new a couple of years ago and has run really well prior to my mini make over.

I've read some posts about BBQing the exhaust which Im going to do this weekend but Im at a total loss, could this issue really be from a plugged exhaust?

The most likely thing that makes the most sense is the carb float and needle valve but they check out fine with the testing. The next thing that makes sense is the fuel pump could just be a chinese junky faulty thing? which is why I'm asking about all these different fuel pumps and the prices of them???

Am I missing something else because it seems so fishy that this suddenly started happening. Anyhow, thanks in advance for any insight to this issue.

Cheers,

Jim

BGW

__________________
This advertising will not be shown in this way to registered members.
Register your free account today and become a member on Buggies Gone Wild Golf Cart Forum

CP241

Sounds to me like typical problems you will find with the cheap chinese carbs. There's a reason they're $15-20 and an OEM Mikuni carb is $250.

I would clean your OEM carb really well and set the float/needle and see if you still have the same problem.

cart around

There are two things to check.
The new carbs come with a clear hose attached to the vent on top. For some reason that hose is plugged on one end. It shouldn't be. Cut the solid end off.

You said gas is coming from the pulse hole for the fuel pump. That could also be the sign of a ripped lower diaphragm in the fuel pump. Read this thread. http://www.buggiesgonewild.com/gas-e...fuel-pump.html

Dabble Inn

are these after market fuel pumps all the same because they look the same all for under $20 with the exception of the one and only "Makuni" made in Japan and sells for $120 ???

I hate to add to the confusion and misconception of the parts brand you mention above. But, The correct spelling for the great reliable carbs from Japan we all grew up with is 'Mikuni'. The cheap aftermarket carbs (that I have had pretty good luck with) are 'Makuni'..

Now what really blew my mind, through a lot of the research I've done I found the 'Makuni' is very popular with some of the high $$$ racing dirt bike teams.... So yeah I'm confused

Jim Dandy

CP241,
What exactly is the reason the cheaper carbs fail? and where can I get an OEM exact for my cart? I don’t have the original. It seems crazy as the cart ran for a few days on the Chinese cheapo. But I guess it’s plausable. Also can you explain how to set the float? I’ve never done that. Thank you so much for the help

CP241

The chinese carbs quality is very poor. Casting of the carb housing, fitment, jetting consistency, etc. are all very poor. They CAN be made to work pretty well if there's no other option, do some searching on the forum and you'll see some hits. But generally, for every 1 person with a good result from a chinese carb, there's 99 other people that the carb caused more problems than it fixed.

Post an ad in the for sale/wanted section on the forum here, i'm sure someone has a spare OEM carb laying around they can sell you.


As for setting the float, there's a lot of different methods. Some more precise than others using feeler gauges, calipers, etc. In the repair manual, it should provide measurements of float height, and etc. I go by my eyes, and i've never had one cause me problems.

Take the float bowl off and first ALWAYS pull the pin and remove the float. Pull the needle out and make SURE it moves FREELY in it's little home. Make sure there's no dirt or debris in the seat at the bottom, any dirt will make it stick open and it can't stop fuel from entering the carb. Helps to blow some compressed air through there so any dirt that may be in the inlet tube blows out as well. Then put the float back in if all is okay. Make sure to use a fuel filter and new fuel lines. old rubber fuel lines can disintegrate internally and those pieces of gooey rubber make their way into carbs and cause problems.

Turn the carb upside down. First press downward lightly and make sure the little spring loaded pin on the top of the needle is not seized. Your carb is new so it should be fine, but I always check. The float should be perfectly level with the bottom of the housing on the carb. See the picture below, this one is for something else, just an image I found on google, but this one is not adjusted correctly. Ignore whatever measurements are on there, This one angles downward, so it will let more fuel in than it should, so it will run rich or flood.




This one below is adjusted better. You can see how the float is level with the flange. This is what you want to see.





Takes a little practice, but once you've done one or 50 it just comes as second nature. Sorry if i'm leaving something out, I just sorta "do" it and don't pay a lot of attention to the steps/details to "do" it anymore lol

trig123

I didn't see where you answered cart around .

Jim Dandy

I found an OME Mikuni Carb for $160 and ordered it. I just couldn't get those chinese cheapo's to work. I also ordered a new fuel pump and am waiting for the parts to arrive. I'll BBQ my exhaust this weekend and will report back once I get the cart back together. Thanks for everyone's input!! Have a great weekend.