Jd 320 fuel starvation?

[Frankman]

Have a mid 1990's Jd 320. I got this from a good friend that was having issues with it. Was having issues with it not running unless the choke was on. Had barely any fuel in filter with bubbles flowing through it like crazy. He replaced both coils and plugs and various other maintenance items thinking it would fix the problem. It did not. I got it home thinking it was just something like cracked fuel lines, or junk in the tank or carb. Pulled tank and all fuel lines. Replaced all of them including the section of hard line as it was fairly corroded. Flushed and cleaned the tank and carb, and replaced fuel filter. It ran great for 2 mowings (i have about 2.5 acres to mow)and is now doing the same thing. Fuel filter is filling with bubbles and tractor will not run unless the choke is on fully. Took off the gas cap as it seemed to be starving for fuel, thought maybe the vent was clogged. No change... Any other ideas? When it started this time as I was mowing it started to sputter a few times, then ran fine for a few minutes, and then eventually stalled. Then would only run with the choke on. I'm stumped! I really hate to throw money at it for a fuel pump or any other items that will not fix it. And help would be greatly appreciated!

 

[Frankman]

Almost forgot! Has a 18 hp liquid cooled Kawasaki vtwin # FD590V-AS00

 

[wschapinjr]

sounds like a fuel line suction problem as there should be no air in the lines. Maybe a fitting is loose? Is the filter housing new? Might put some silicon around where the bowl fits against the metal top and see if that eliminates the problem. If it does then I would replace the entire filter assembly.

 

[Frankman]

This tractor just has a replaceable inline fuel filter... The previous owner and I both replaced it... I'm stumped?

 

[JD 420]

A quick test to try is disconnect the fuel line from the fuel shut off valve located just before the fuel filter and put the fuel line to the filter in a container with fuel in it and start the engine and watch to see if the air in the fuel problem is fixed. If there is no more air in the fuel at the filter then the problem is before the filter on the tank side. If there is still air in the fuel the problem is after the shut off valve towards the engin. You can also blow a SMALL amount of air into the line at the shut off valve going toward the tank and listen for any leaks. Hope this helps.

 

[rabtfarm]

I just had a diesel fuel feed issue whereby the short plastic tube inside the fuel tank had perished and was leaking air into the suction side. Does your fuel line drop into the tank from the top like mine, or does it feed from a bottom fuel feed? These new gasoline formulas will melt steel given the chance...plastic and rubber don't last long.

 

[Gumby542]

I have a 94 320 that does the exact same thing. I've been worki on it for a month now. New lines, clean carb, clean tank, new filter, new fuel cap, blew all lines out. Got black crud in filter. Replaced again. Next step was to disconnect fuel line at the carb, check to make sure pump is working correctly.
Really seems like a vapor lock condition, but there doesn't seem to be much heat around the line

 

[Frankman]

Gumby, let me know if you make some headway on this. I will be sure to do the same!

 

[Gumby542]

Absolutely. This thing has been frustrating me for a month now. So much, I went and bought another tractor. I really like my 335 now

 

[Frankman]

Wish that was an option I could do also.... But not one right now.

 

[Eric Barney]

The two places I would look for air entering the fuel system first: (and second.) The pickup tube in the tank. These corrode from the ethanol in gasoline, and may be clogged, or have pinholes in them. The fuel pump. May have bad check valves, or leaking diaphrams. Look for fuel leaking from the vent hole in the pump body. Newer replacement pumps have a vent tube to safely direct the fuel away from the hot muffler should a leak start. If this tube does not exist on your fuel pump, it is probably the original, and it is bad.

The carburettor may also be getting re-clogged from tiny pieces of the fuel pump's disintigrating rubber diaphrams. I have experienced this many times on engines equipped with mechanical pumps and carbs. Inline filters are frequently upstream of the pump and carb. Particles from a failing pump are free to enter the carb. and clog the jets.
Since you did mention the hard line in the original post, I assume that you have already changed the tank pickup tube.

 

[Gumby542]

I cleaned the tank and just found more black chunks in the filter. Guessing maybe from pickup tube?

 

[Frankman]

My pickup tube is metal. I hate to take this pile to a dealer.

 

[JD 420]

Where is the fuel filter located in the line on yours. It should be right after the fuel shut off valve but before the fuel pump. Disconnect the fuel line from the shut off valve and stick the fuel line going toward the engin in a container with fuel in it and see if the bubble go away and it runs correctly if it does then you know the problem is between the tank and the shut off valve. If it still has bubbles in the filter then you know the problem is between the fuel pump and the shut off valve.

 

[Frankman]

The filter is just after the shutoff valve. Will try an mess with this mess in the am... Thanks for the ideas.

 

[Gumby542]

SO here's where I'm at after today. With fuel filter out, I get a very steady stream of gas from out of the line. Once the fuel filter is in, I get no fuel flow. I have tried with and without the cap and with 3 different fuel filters (one from the tractor, one from my running tractor, one new one). I still have the same issue where the tractor filter goes empty and it stalls out

 

[Gumby542]

Another few hrs in- the hard piece of tubing that connects the tank line to the shut off line was plugged. I now have fuel coming from the filter in a steady stream. However the tractor is still stalling out. I believe that my next step to rule out is fuel pump. I'm going to take off the fuel line into the carb and see what I get for fuel. After that, I go to carb. We'll see how I make out tomorrow

 

[deerseeker001]

i just went through this with my L130 TOOK it in to my repair guy it was a dirty carb,runs like a clock now

 

[Frankman]

Gumby, sounds like we are definitely having similar problem..... I have not been able to mess with mine. I have a great neighbor who let me use his zero turn to mow.... Hope to figure something out this weekend if possible. Have a friend whom was a small engine tech for years.. He is also stumped with this issue and is leaning towards it being a fuel pump issue?

 

[rabtfarm]

I was looking at the 320 JD Parts catalog and your engine is not what I would call a simple lawn mower: fuel injected with a fuel pump, regulator, etc. I would definitely have a JD dealer/repair shop look at this. Some make house calls if the unit is in pieces everywhere.