looking foe advice on fuel delivery problem

[Jim Hunziker]

I have a Case DX-29, that has a fuel delivery problem, and I don't know where to go from here. Two weeks ago as I was mowing even though the fuel tank was 3/4 full, the engine stopped from what sounded like a lack of fuel. I took the fuel line off, and the tank drained back into the fuel container. I tried to bleed the fuel system to get the tractor going again, and although fuel would come out of the bleeder nut just prior to the pump, I could not get diesel bled to the lines to the injectors. A friend who repairs tractors came over and tried, and he couldn't bleed the system either, and he didn't want to tear everything apart in the field, so I ended taking the tractor to a repair shop. They said that they bled the system without difficulty.

The tractor starts easily now, but when I get it up to speed to use the mowing deck, after a few minutes of mowing the engine starts sputtering, loses power, and almost dies. I can slowly get the engine back up to speed and start mowing again, but the same thing happens again. Suggestions as to where to go with this so I don't need to trailer it back to the repair shop? I've been using fuel additive (Sea Foam), and am trying to not have to take the fuel tank out to check it, but that may be the next step unless there are other suggestions. It is new diesel, and I didn't see water in it. Can diesel go bad?

Any suggestions?

Thanks.

Jim
206-228-2101

 

[Roadworthy]

Do you have a vented cap on the tank? The vent could be plugged cutting off fuel flow. You could have a blockage at the output of the tank. Get a clean bucket and start with the first connector after the fuel tank. Break the connection and see if fuel flow is good into the bucket - say for a quart or two. This will establish whether the fuel can flow freely from the tank. That may help narrow the problem down. If flow is good you can then proceed through the fuel lines.

 

[DEWFPO]

Loosen the cap on the tank. Is is possible the pump is sucking in air from a loose fuel supply line?

 

[BlueKnife]

When was the last time the fuel filter was changed? Diesel can go bad, but it takes a while if it's stored properly.

 

[dodge man]

I’d change the fuel filters, sometimes there is more than one.

 

[Jim Hunziker]

Thank you for the suggestions. Yes, initially I changed the fuel filter (and the air filter for that matter, just for the **** of it), have new diesel, and after your suggestions tried loosening the cap to see if it was a plugged air vent (which the cap does have). None of that helped/made a difference. When I first fire it up, it works fine at full PTO RPM's for about 4-5 minutes, then dies down to stall unless I push in the clutch and stop all machine activity. After 1-2 minutes the engine slowly speeds up, but there is no power to the engine for another few minutes. After another few minutes of running I can go for another few minutes of mowing before the same thing happens again.

I strongly suspect there is an intermittent fuel blockage from the tank, as when the fuel line is unhooked the fuel will flow freely. No debris is seen in the fuel as I drain the tank. If it is not debris plugging the line, I suppose there may be a "flap" in the inside surface of fuel line that intermittently "flaps" open as full fuel flow happens. (I had that happen on a vehicle many years ago.) Regardless, whether it is something in the tank or something in the line, I will need to pull the top of the tractor off to get the fuel tank out to clean it and access the fuel line to replace that. I've been trying to avoid this, as it will take a while, but guess the time has come.

Thanks for all your suggestions and time answering.

Jim

 

[BrokenTrack]

A sticking exhaust valve will mimic fuel delivery problems too.

The only reason I mention it is, they will often stick after the engine gets up to temperature. You get the same bogging down, and think it is a fuel problem, but its not.

I am not convinced that is your problem as you use sea foam, but it is something to remember if everything else checks out okay.

 

[dodge man]

I’ve read where a leaf or similar debris gets in the tank and will plug it up. One last check, make sure the lift pump is working. Often they make a clicking sound. The main injection pump will often suck enough fuel to sort of keep it running.

 

[BobG_in_VA]

This may sound "weird", but Case has had many years of issues with its fuel lines...good friend of mine had a Case (65hp) that mimicked exactly what you are talking about...a 70 year old "real" farmer told him to check the fuel lines/replace them...he did and all is now well..it seems once the tractors get some age on them the non-metal full supply lines weaken and then when you need the fuel the most, the lines start to collapse. This might be your issue. Good luck.

 

[the old grind]

My DX26 (also NH TC33DA) fuels through the (closed) hood. There's a 'spill cup' around the filler neck with a drain hose. Tree duff clogs the drain and allows water to collect above the rim of the vented cap. On cool nights this water gets sucked into the tank when airspace in it contracts and siphons it. (These are all Shibaura-built machines with polymer hoods.)

In Winter this has caused me to have to remove the Case's fuel filter and thaw the ice cube that froze in it. I end up propping a heat gun to warm the lines so that water can be purged. This happened enough times with the Case/IH that I removed the 'catch collar' from the NH's filler. Using 'Mister Funnel' when refueling doesn't spill much anyway.

Water in fuel can settle in enough places to make it difficult to remove all of it. Winter isn't the only time it can impede adequate fuel flow. If the problem here is as simple as mine was, (hope so even if not the same) maybe the same preventative will help. btw, if you use the "Mister Funnels", label them for gas & diesel separately to avoid cross-mixing fuels.