Diesel issue

M

Mith

Active member
Guys, here is one I'd like to hear your thoughts on. I think I have it solved, but dont know for sure.

Its a John Deere out front rough mower (golf course). 30HP turbo diesel I believe.
Initial problem is that is was pushing out alot of white smoke at full speed, and was sluggish. Eventually it just wouldn't start.
He noticed that fuel was not coming out of the filter to the injection pump. He bypassed the filter, but suspected the fuel pump wasnt working.

I got involved here, went out to have a look. Fuel pump was pumping, so I blew out the fuel lines, added new temporary inline filters (the main fuel filter was very dirty) and beld the air out.
Started it up, it ran just fine.

Got called back today it had stopped in the middle of the rough next to a fairway (not ideal). Recleaned the lines. The inline filters had alot of dirt in them by this time. It fired up and ran fine. Must be a load of junk in the bottom of the tank that keeps blocking the line to the pump.
Just as I was leaving it started with the white smoke and sluggishness again. I dashed back over to see air bubbles getting pumped into the inline filter from the pump.
Must be an air leak somewhere. Only thing between the tank and the pump is a sediment bowl. Figured it must be sucking in air through there. Bypassed the sediment bowl and its back to running fine again. He's mowing with it all day tomorrow, so we'll see how it gets on.
I'm thinking, with the restriction from all the junk in the tank the pump is drawing air though a leak somewhere in the sediment bowl.


Its the white smoke thats confusing me, would an engine that is starving for fuel push out (alot of) white smoke? I was under the impression white smoke was unburned fuel, indicating too much fuel.

I'm fairly happy its a problem with the fuel system as when it has trouble the filters are full of air, when its fine the filters are full.
I'd love to clean all the junk out from the tank and give it a deep clean, but its their only rough mower so its cant be out of service for that long.

I'm hoping I've got it sorted, he'll be on the phone first thing tomorrow if it isnt (they mow at night).

Any thoughts, I might be barking up the wrong tree here.
 
Engine Emits Blue or White Smoke
1.Cranking speed to low
2.Injection pump timing incorrect
3.Injection pump automatic advance is faulty or not operating
4.Injection nozzles faulty or sticking
5.Excessive wear in liners and/or stuck piston
 
The white smoke is from too lean on diesel. Same happens as far as white smoke when going downhill & backing off the throttle & letting the tractor push the engine. I had a 6 cylinder MF2705 do the same thing, start white smoke, then die. Had gunk in the fuel tank blocking the outlet. It also pulled air into the system from somewhere when the line got blocked. Time to take the fuel tank off & flush out.
 
Sounds like this has the same problem as your MF then Dan.
He said the problem was getting worse over 3 weeks before we got involved. I think it must be junk in the tank, its just been compounded by the fact he didn't get the tank cleaned on the first sign of the problem.
Cheers
 
Paul, dont I know it.
The way the tank is designed the only way to get fuel/junk out is to take the tank off. I told him this, but he said he cant have the machine down for that long, it needs to wait till winter.
 
Mith said:
Paul, dont I know it.
The way the tank is designed the only way to get fuel/junk out is to take the tank off. I told him this, but he said he cant have the machine down for that long, it needs to wait till winter.
Click to expand...

Can't you disconnect the outflow of the fuel tank and flush it that way?
 
Jim,:wave:
Schedule a tank removal and cleaning at sun set. Clean the tank and reinstall the tank before daylight. It's call the graveyard shift.:pat: Better yet, have them buy another tank to have ready to just remove and replace (R&R) the old tank with a new one. It sounds like it could be an ongoing fueling problem and could just be mircrobes living and breeding and jelling the lines and/or jets and/or fuel passageways. Diesel and Jet fuel tanks need to have a way to sump the tank from the bottom to remove any accumulated moisture, which the mircobes live in.:shitHitsFan: A drain valve that can be reached easily daily needs to be installed.;) You might research Bio-Bor http://www.skygeek.com/biobor16oz.html to add in the tank.:cool:
hugs, Brandi
 
My tractor had junk in the tank when it was new, I drained and flushed the tank and have never had anymore trouble. I reused the fuel, just strained it through a rag before putting it back in. There was a screen type filter in the tank outlet that I removed when I drained it. Might be worth a try and doesn't take very long, an hour at the most.
 
Well guys, no phonecall yet, so it must still be working.

The tank is moulded and is part of the bodywork. Its very inaccessible, the hoses go through the top, and you cant see down the filter tube. There are no drain bungs on the bottom of the tank. Tank has to come off to be flushed, no 2 ways about it.

Brandi, thats what needs doing, but I'm not doing it unless someone wants to pay me to be up all night. I can do little more than make suggestions.

Cheers guys, I'm feeling a little more confident in what I figured to be the problem. I cant do anything to solve the problem though until they say however.
 
Mith said:
Well guys, no phonecall yet, so it must still be working.

The tank is moulded and is part of the bodywork. Its very inaccessible, the hoses go through the top, and you cant see down the filter tube. There are no drain bungs on the bottom of the tank. Tank has to come off to be flushed, no 2 ways about it.

Brandi, thats what needs doing, but I'm not doing it unless someone wants to pay me to be up all night. I can do little more than make suggestions.

Cheers guys, I'm feeling a little more confident in what I figured to be the problem. I cant do anything to solve the problem though until they say however.
Click to expand...

I love the fact that the newer generation tractor design engineers seem to be more worried about looks than maintainability...:)

I guess that is because most of them never were on a farm...:rolleyes:
 
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