Ford 3000 Diesel engine "burps" while idling

[Slasham64]

I couldn't think of a better way to describe the event except "burps." My Ford 3000 Diesel has always idled smoothly until recently. About every 10 minutes, it "burps". IOW, it revs for a second and settles back to smooth idle. I don't think it's what some mechanics call "stumbling" which I take to mean mis-firing but I guess that's another way to look at it. I just changed the fuel filter and the fuel has been refilled several times (so no water in fuel). This week I discovered a fuel leak around the shaft where the air is cut off when you stop the engine. It doesn't leak all the time, I think it's leaking only when air is off. That seems to be a strange place for a fuel leak, but I don't know diesel engines very well. Any clues?

 

[sotxbill]

Make sure the fuel cap is not venting correctly and creating a vaccum on the tank... also make sure the return line is not stopped up and letting excess fuel flow back to the tank...

 

[Slasham64]

Thanks sotxbill. I will try both options you suggested. Since it does this while idling (and not bouncing across the farm), can I just remove the fuel cap to rule out a venting issue?

 

[wore out]

I couldn't think of a better way to describe the event except "burps." My Ford 3000 Diesel has always idled smoothly until recently. About every 10 minutes, it "burps". IOW, it revs for a second and settles back to smooth idle. I don't think it's what some mechanics call "stumbling" which I take to mean mis-firing but I guess that's another way to look at it. I just changed the fuel filter and the fuel has been refilled several times (so no water in fuel). This week I discovered a fuel leak around the shaft where the air is cut off when you stop the engine. It doesn't leak all the time, I think it's leaking only when air is off. That seems to be a strange place for a fuel leak, but I don't know diesel engines very well. Any clues?

Take another look, I think that you will discover "the shaft where air is cut off" is actually on the injection pump and cuts off fuel (NOT air) to "kill" the engine. If it leaks fuel it also may let air into the fuel system while the engine is shut down.

And a little air in the I.P. is a common reason for the the issue you are having.

Can you post a photo?

 

[Slasham64]

Wore out, I was suspicious of that leak being the culprit, even though I had been told it was air supply. Does this require fuel pump replacement? Or can I repair the pump with new seal? Unfortunately, I am not near the tractor to get a photo, except every two weeks or so. Thanks for helping a novice.

 

[sotxbill]

Wore out, I was suspicious of that leak being the culprit, even though I had been told it was air supply. Does this require fuel pump replacement? Or can I repair the pump with new seal? Unfortunately, I am not near the tractor to get a photo, except every two weeks or so. Thanks for helping a novice.

There are youtube videos on how to replace the orings on the cutoff lever.. a bit tricky but doable...

 

[Slasham64]

There are youtube videos on how to replace the orings on the cutoff lever.. a bit tricky but doable...

OK. Good to hear. I'm a YouTube Certified Mechanic. LOL

 

[showcrop]

Sounds like sucking a slight amount of air. Was it doing it before the filter change?

 

[Slasham64]

Sounds like sucking a slight amount of air. Was it doing it before the filter change?

Yes. It was doing it before the filter was changed. I thought filter or adjoining seals were leaking air too. But the burps continued. I have ordered o-ring kit from YT to install on the injector pump's throttle and shut off shafts. Shut off o-rings are definitely leaking. Maybe that will fix it. Thanks showcrop