Yanmar 324 - Engine Intermittently Running Bad / Loss of Power / Stalling Out / Not Starting

[Mahonroy]

Hello, I have a Yanmar 324 that is only a few years old with about 180 hours on it. I have kept up with all service items.

Recently I was using it and the engine all of the sudden started to stutter, loose power, and stall out. Difficult to get started again. I tried replacing the fuel filter. I was then no longer to get it started (I believe I probably introduced air into the fuel line). So I cracked open all 3 of the hard injector lines to bleed the fuel lines, and I shot compressed air into the fuel line leading back towards the tank. I kept trying to start it and after 20ish minutes it finally started, ran a little rough, then ran perfectly fine.

I put about 8 more hours on the tractor and it was running perfect. Then all of the sudden the problem returned.

I tried blowing compressed air into the fuel line again, but it didn't work (I'm not even convinced this was the problem to begin with). The tractor is still running really bad with no power and constantly stalls out.

Any idea what the problem might be? Any help or advice is greatly appreciated.

 

[Rustyiron]

Bad fuel would be my first guess, or at least a possibility.
Usually there's a little lever or knob to manually pump fuel through the lines and fill the last little bit of the filter if you are away from an air compressor.
If you end up with another filter, cut apart the "bad" one and look for discoloration.

 

[freightboy]

Did you change both the fuel water separator and fuel filter? Have you checked to see if the lift pump is pumping fuel properly? When you turn the key on, does the fuel rack click once, twice, or shutter? Have you checked the amperage to the fuel rack to insure the pull coil is actually pulling? You may want to disconnect the line prior to the fuel lift pump and see if it is restricted. If the flow is restricted fuel may not be getting through the system properly.

 

[aba4430]

I own a SA425 tractor and periodically browse YouTube for tractor related content. I found this on YouTube and it may help you. Good luck.

Starting/Running Issues

 

[Mahonroy]

I own a SA425 tractor and periodically browse YouTube for tractor related content. I found this on YouTube and it may help you. Good luck.

Starting/Running Issues

Thank you for posting that video - that turned out to be the exact same issue I had. Something is in the gas tank clogging the line, and blowing compressed air into the line freed it up.

Now I just need to figure out how to get whatever debris is in there out. I ordered a fuel pump with a hose, in hopes I can suck all of the gas out (along with the clog).

 

[Gogetter11509]

A screw from the hood was in my fuel tank. Replaced it in the hood. After running the tractor 3 hours, the screw was found laying in the neck of fuel tank again. Pretty sure that's how it got in the first time. It's in my tool box now. Problem solved I hope!

 

[aba4430]

Your running issues may be resolved, but check your hood for potential cracking. These hoods are known to crack and the warranty for replacement might not extend to 10 years for the hood. I have a 2023 purchased SA425 with ~160 hours now. I manipulate the hood very gingerly during checks and cleanings; no slamming, opening with even pressure side to side etc. No issues presently, but I am expecting breakage some day. It creaks/groans a bit when it raises. Quite a poor design. My understanding is that they have beefed up the hood support design due to the issue.