Workhorse ST350 Won't Rev Up and Move

[1arunem]

I had one with a chinese carb that would barely turn over. Checked oil and it was way over full. Crankcase full of fuel.

Carb was leaking into crankcase causing hydrolock. Just fyi.

[JPonLKN]

Originally Posted by 1arunem

I had one with a chinese carb that would barely turn over. Checked oil and it was way over full. Crankcase full of fuel.

Carb was leaking into crankcase causing hydrolock. Just fyi.

That would likely have been a poorly adjusted float, not closing the needle valve when the bowl was full of fuel. Quality control on these cheapo parts is poor, if done at all. I've bought some of these cheap carbs for these motors and other small engines and they usually work, but sometimes need cleaning and adjusting so they work correctly.

[Futility Vehicle]

The old carb has a broken post that holds the float pin. Last year, I put it in the sonic cleaner, and the pin would not come out. I tapped it with a punch, and the post snapped off. I glued the old post in place with epoxy to make it run while a new carb was on order, and the carb worked so well, I left it alone until the epoxy gave out. By that time, the new carb had been here too long for a return.

I gave up on the first Chinese carb and installed a new Chinese carb today. The cart ran fine until it warmed up. Then the same problem started again.

Are these carts supposed to have strainers on the fuel pickup? I'm wondering if junk is getting sucked up against the tube after the cart runs a while. My tube has no strainer. Just a filter on the way to the pump.

The filter is new. Chinese carbs always seem to come with new filters. I also replaced the fuel line from the tank to the carb. The tubing that came with the new carb didn't seem all that great, but I figured it was not likely to have holes in it.

I turned the engine over with the carb disconnected, and fuel came out of the pump. I wouldn't say it was forceful, but it did come out.

The cart acts like it isn't getting enough gas, but this only happens when it's hot. Removing the fuel tank cap doesn't help.

The oil dipstick seems normal. The oil cap is not threading right, so I am looking for a new one. Not sure which part to get.

[Futility Vehicle]

Is there any possibility the oil cap is the problem? I don't know much about engines. For all I know, an oil cap that won't seal could screw up the engine vacuum and prevent the fuel pump from working right.

[Futility Vehicle]

I got the cap to seal correctly. It appears the threads on the engine are not perfect, but I can work around them.

When I put the cap on right, the cart took off and ran fine. Then halfway around the house, it slowed down again.

When I put it between forward and reverse so there is no drag on the engine, it will slowly rev up to full speed.

It's not getting fuel, but I can't tell why.

[StoveBolt]

I had one where the pickup tube in the tank was loose at the fitting (both plastic glued together) and was sucking air.

[trig123]

Put a meter on your battery and with wheels off ground rev it up wide open. Make sure its not overcharging. If so then the starter/generator will choke this engine . You should see around 14 volts at top rpm's .
Is the driven clutch ( one on rear axle working correct )
How does it run with air filter out ?
I didn't read the entire posts but have you checked the compression ? with throttle held wide open.
These engines are pretty simple.

[Futility Vehicle]

I have not tried to run it without the filter. I assume the clutch is okay because the cart behaves fine when it gets gas. I can try checking the charging voltage.

I'm wondering if I should replace the fuel pump just for the hell of it.

[Futility Vehicle]

Originally Posted by StoveBolt

I had one where the pickup tube in the tank was loose at the fitting (both plastic glued together) and was sucking air.

The fuel pickup apparatus seems to be pretty cheaply made, and mine is not in great shape. I don't know why the cart would run well cold and then bog down when hot, though.

The fuel filter always seems to be mostly full of air. Is that normal?

[trig123]

Originally Posted by Futility Vehicle

I have not tried to run it without the filter. I assume the clutch is okay because the cart behaves fine when it gets gas. I can try checking the charging voltage.

I'm wondering if I should replace the fuel pump just for the hell of it.

When it stops running remove the carburetor bowl and see if its empty. If it is then yes your fuel pump might not be any good but I sort of doubt that is the issue
Again did you tell us what the compression is .