1990 EZGO 2 cycle Marathon SLow to start, must hold choke to go

[usedoem]

Howdy,

Just picked up my first cart for the kids to play with. Its a 90 EZGO with 2 cycle Marathon engine. It runs good for the most part. Good enough to play with anyhow but its not running properly...

When you first get on it, it takes a good 3-4 minutes of holding pedal and messing with choke to get her going. Once you get it going you have to mess with the choke to have it run properly. Holding it halfway out does the trick most of the time. THe longer you drive it the better it gets however its never "right". It will go without having to hold the choke once you've ridden for a while but it'll go much faster if you pull choke out and release it every few seconds. Otherwise it's really sluggish.

I'm not one of those Aholes that didn't try anything to fix it before asking for help. I've googled, youtubed and forum searched for hours. From my research I figured it was a fuel issue. Not getting enough fuel. I cleaned the gas tank vent tube, Put all new fuel lines, new fuel pump and completely disassembled the carb, cleaned it and put back together. Added new spark plug, checked the spark visually, it seems strong. I'm not certain what else to do. I'm going to check the compression on it just for giggles here shortly but I don't think that's it. Also the battery drains overnight on it. I have to charge it for an hour in order to drive it. Plan on picking up a new battery this week. I assume that can't be the issue either.

Any help is much appreciated. Like I said this is my first cart. I've only had it a week or so. Love it but would love it much more if I didn't have to play with the choke while riding it lol.

Thanks!

[93yellowclubcar]

Welcome to BGW!

Sounds like a classic case of bad crank seals to me. How is the air intake system, sealed well? Air leaks on a two stroke can cause bad problems like yours also - bad crank seals are basically a big air leak.

[usedoem]

Thank you

Ah yes I forgot to mention. The intake system seems air tight. Had some oil in the intake tube for some reason. Wiped it out, didn't purchase a new filter yet but blew it out with 120 psi of air. Bad crank seals eh? Sounds expensive. As long as nothing needs machined or anything I should be able to do it myself though. I've rebuilt a few 2 stroke dirtbikes in my youth. I'll have to check into that. Thanks.

[usedoem]

Forgot to mention I noticed it had a fuel leak as well. I didn't look much into it I just put a petcock in the fuel line when I noticed it until I had time to clean the carb. I figured the float was stuck. Have me wondering if something else now. Is there a place I can order a PDF download of a manual for this beast?

[cart around]

As you were describing the problem, I was also thinking crankshaft seals. Here comes the big BUT.
But, you also mentioned oil in the intake, and a fuel leak.

That sounds like blow back from the reed valves not sealing properly.

You have only had it for a week. Is it possible that somebody got frustrated, and sold it to you?

We don't know its history, so there are 3 things I would look at.

#1 Crankshaft seals. That means removing the engine, clutch and flywheel. $15

#2 Remove exhaust pipe. Check for being plugged with oily carbon. While it is removed, look inside the exhaust port, move the piston up and down, and make sure that you are not looking at a square hole in the side of the piston. Free. (Your 3pg would have 2 square holes. Still bad)

#3 Remove the intake side. Make sure that the reed valves are clean, and close completely. Also check the rubber seal that mounts the reed cage. There is a threaded hole in the top of the intake manifold. It should be sealed with a 6 mm screw. Also free

Lastly, mix your gas 128:1. One ounce of oil with one gallon of gas.

[usedoem]

Thank you for the thorough directions. I'll yank the engine and do some inspection when time permits.

I purchased from a guy who inherited it from his father in law who had it for a very long time. He claimed the engine was rebuilt at some point but by the looks of it, it was in the 90's if at all. When I purchased it he told me a carb cleaning would solve the issue. It was just dirty b/c he lived on a gravel road. He seemed honest enough and didn't appear to be in need of money so assume it was ignorance over dishonesty. I don't think it was dumped on me. He hadn't attempted to fix it, they just used it as is. It's very operational. Once you get it going, as long as you hit the choke now and then she's good. Plenty of power. Just annoying more than anything as since it's mainly for the kids I figure they don't want to deal with that. They don't seem to mind though. They've already worn a track in the yard lol.

I was hoping it was a quick fix and I wouldn't have to pull the engine. When I took the fuel pump off I tore it down to clean it up and one of the plastic bladders had a hole in it on the very edge where it seals. I figured I had found the issue at that point. New pump proved me wrong.

[cart around]

My ripped pump diaphragm was the root of all of my issues. I found that out after I performed the HEI conversion, and while I was in the process of changing the crankshaft seals.

[my1423]

Before you tear it apart.
Put the rear end up on blocks.
Take a can of starting fluid or wd40 and put a long straw on it.
Take off the seat.
get it started and have someone keep it going.
Keep the engine at a steady rpm.
Take your spray and spray a little behind the engine clutch at the crank and see if the engine revs up. Little if your seals are bad too much could rev it to the moon.
Spray a little in the fan shroud.
If the engine revs you have bad seals.

Could be bad seals, Bad rings, broken piston, Bad reeds, plugged exhaust carbon in port,

Next up would be a compression check, then pull the exhaust, then the intake.

[usedoem]

Finally had a chance to look into this a bit and thought I'd update and get more advice. I was going to order a rebuild kit and just go at it. Figured I'd do a compression check first and came back with 135psi. I pulled the reeds out. I notice one on each side, opposite of each other are not seating completely. There is a very very small gap between the reeds and the reed body could stick a sheet of notebook paper, maybe two between it. If I hold it to the light and look through I see a small bit of light. Not sure if that is enough to cause the issue or not.

I went ahead and ordered new reeds just now from Boysen. I also found a new carb on eBay for $50 so went ahead and grabbed it as well as new air filter, plug & gasket kit. Spare parts if nothing else I figure.

I'll report back after I install the new reeds here in a few days.

[usedoem]

Those reeds were a PITA to find BTW. If anyone else is looking for them Part number 650 from Boysen. $40 shipped