Ventrac 4500Z quits unexpectedly

[SwampDog67]

I'm running a 4500Z with the Kubota engine. The machine only has 300 hours on it but I'm now having troubles with it stopping unexpectedly. Sometimes it quits after 5 minutes and sometimes it will run fine for 10-15 minutes. Seems to idle forever fine but as soon as it's under load the issue begins. Changed the plugs, air filter is clean and even added some gas line antifreeze in case of moisture. I could see some blue flame from the muffler at one point but it acts like its starving for fuel.

It will immediately re-start after stalling and might run 1 minute or 10 before stalling again.

Thoughts??

 

[zmountaineer]

Does it putter out or is it abrupt? I had an issue with my e-brake where it was a little loose. I would be moving and hit a bump or something and it would move and kill the engine immediately. The sensor thought that the brake was on and the tractor will not let itself move if the brake is on. I fixed it by tightening up the nut on the brake bar down by your right foot.

 

[prs]

I would also suspect fuel starvation. Hopefully a very simple replacement of inline fuel filter will do the job for you. If fuel tank outlet is blocked, adding a section of fuel hose to the outlet of a CLEAN fuel filter will let you blow it back into the main tank. Then it would run, but you would need to clean the tank. If it is the bowl or bowl float, do a write-up with pics for us. Looks like a tedious job just to get to the bowl. Fuel filters are cheap for this machine (WIX) and I would not use fuel line antifreeze (alcohol) if I could avoid it.

prs

PS: Also make sure your choke is not partially closed.

 

[sandman2234]

Kubota engine means diesel doesn't it?
David from jax

 

[prs]

Kubota engine means diesel doesn't it?
David from jax

More often than not your assumption is correct, but not this time. The 4500Z is the 3 cylinder gasoline engine.

prs

 

[mferry]

Check the vent on the fuel cap. Possibly a sticking float on the carburetor.

 

[sandman2234]

More often than not your assumption is correct, but not this time. The 4500Z is the 3 cylinder gasoline engine.

prs

Just can't get a break, heck I loose even when it is a sure thing, lol.
David from jax

 

[Tony H]

Check the vent on the fuel cap. Possibly a sticking float on the carburetor.

I second this. Seems sand spiders love to clog gas vents. Quick check; Loosen gas cap and sees if problem goes away.

 

[John Joseph McVeigh]

I second this. Seems sand spiders love to clog gas vents. Quick check; Loosen gas cap and sees if problem goes away.

I third this. Vented fuel caps can get clogged by, e.g., fine debris generated when mowing grass, especially in dry conditions.

 

[Tony H]

Some other thoughts.
Next time it quits, Open the gas cap right away and listen for air to suck in the tank. That will indicate that the tank is not venting and causing a suction thereby staving the engine.

One issue I had on a regular push behind lawn mower. I am not sure how your carburetor is set up as far as Needle Valve and Seat are concerned. This very new mower I bought for $5 had a run out of gas issue. Owner was so frustrated, I got a sweet deal. Anyway what it ended up being was the Rubber Seat (Brigg & Stratton) got deformed. Not sure if it was from Ethanol gas or whatever the guy put in the tank to store it over the first winter. But the Rubber Seat deformed and would only trickle gas into the bowl. The engine would consume more gas then the flow into the Carb Bowl. It would run out of gas. 30 seconds later you could start the engine, first pull, and it would do the same thing.
Still betting on clogged Vent