Diesel mystery

JHesler · Oct 25, 2016

My JD 310 backhoe has been running great for years. A couple days ago the injection developed a problem. Was running fine for a few hours then lost power and quit.

Here's what I've checked... Plenty of fuel in tank, Replaced fuel filter, New lift pump, Plenty of fuel flow to injector pump while manual priming, Checked injector pump inlet filter it's clean, Checked and blew out return lines all clean, Checked return line pressure valve (check valve) not working great but it is clear and relieving pressure from the governor chamber. Checked air cleaner and ducts all clear. Bled air out of fuel at injectors. Checked shut off solenoid its clicking and sounds like it's moving the right parts inside.

Here's what it does...Starts and runs great for about a minute then slowly fizzles out and stops. Let it set for a while and it does the same thing.

I suppose getting into the injection pump is my next job but I can't imagine what would be going on inside the pump to account for such behavior.

Maybe I'm just missing something obvious and would greatly appreciate you guys sharing your ideas.

01gentdc · Oct 25, 2016

hi j ,,, well my perkins 354 in my 750 mf pulled a similartrik 2 yrs ago ,,. you seem well versed with all the causes and I know enuf too ,,. but yet I couldnot bring myself to believe the injector pump had failed ,, the motor didn't want to start and did not have hardly any power .and would just for no reason shut itself down , and it seemed like this happened overnite ,..after exhausting every cause ////I had the injector pump rebuilt at interstate injectuion in Seymour ind ,,. it was in horrible shape ,,.I had to find another pump for parts that were ruined ,,. BUT that was only half my problem ,. the injector pump helped but it still was not powering up rite ,,. turned out the turbo needed rebuilding as well ,. went to same shop , ,couple dAYS LATER I HAD MEAN LEAN RUNNING POWERFUL MACHINE

Philip d · Oct 25, 2016

We had the same problem on our M8200 kubota this summer. We ended up replacing all the rubber fuel lines and the kubota mechanic advised us to bypass the water trap and use a steel inline fuel filter in its place and have had no issues since. If your is starting fine than fizzles off and quits it sounds like it's drawing air into the fuel line somewhere.

tim s · Oct 25, 2016

Take the timing window off and see if it runs then your return is clogged some where the check ball is clear it will appear to be open and not be...

01gentdc · Oct 25, 2016

yes , the return was not mentiond,,;4020 deeres hate that when that hap;pens ,, but they will continue to run ,, at least mine did .

JHesler · Oct 25, 2016

Thanks Tim. Blocked return is the culprit that comes to mind but I had the the check valve out. The glass ball is clean and the spring is working. Good flow in the out direction, just doesn't seal very well in the other direction but that shouldn't matter (or should it?). I ran it with the rest of the return lines disconnected at the check valve... same results and I'm sure the return lines are not clogged. I'll try removing the timing plate tomorrow.

Dieseltech · Oct 25, 2016

Running with the timing cover loose like Tim said is a good way to load otherwise dead machines on a trailer too, have done it several times to keep from pulling pumps off for repair in dusty fields..

Rons b · Oct 25, 2016

I had the same problem with my case backhoe and it turned out to be a stuck valve

Determined · Oct 25, 2016

Sounds like injector pump to me.

One faint hope test you can do is run a piece of hose from a jerry can to the lift pump and test run it.

This will eliminate the remote chance there is something floating around in the tank causing intermittent fuel blockage or possibly a rubber line that is collapsing internally once warm.

Does yours have the glass filter where you can see if you are sucking air in somewhere?

JHesler · Oct 25, 2016

Thanks Ron. Would be easy enough to pull off the valve cover and check. But one stuck valve stopping the engine? Could be. The 310 only has three cylinders. But I can pull an injector line and
it runs on two.

JHesler · Oct 25, 2016

Yes, glass filter and no rubber lines. They are all steel except where the return line connects to the injectors.

Al Baker(pumpman) · Oct 25, 2016

Classic signs of flex ring failure. Time for a pump reseal. Not expensive, not difficult to R+R. Pick a good pump man and Send her off. High price doesn't mean better, low price most times isn't good. Few phone calls may save you time, and money. Call around , Ask questions. This time of year some shops run specials to make up for things winding down for winter. Maybe a few % off, or free shipping. I give 50 bucks off to anyone who is on this board. Should cost 350-400 bucks. I would be glad to help you out if you are interested. Good luck,,, Al 231/757/0064

JHesler · Oct 25, 2016

Thanks Al. What is the "flex ring"? The drive shaft seals? This is a Roosa Master JDB pump. The shaft and seals stay on the engine when the pump is removed.

Al Baker(pumpman) · Oct 26, 2016

Flex ring is the nylon washer that holds the two halves of the weight retainer assembly. Its job is to cushion the weight basket when there is any changes in speed. (Makes it smooth). This flex ring gets hard and brittle with age. It falls apart and gets ground up while the pump is spinning. The pieces are what plug up the ball check, and the return lines. This causes pressure to build in the pump housing not allowing the plungers to push back out to take a fresh charge of fuel.. Pull the timing window off and look in the corners of the window. You will see what looks like coffee grounds. This is what is left of the flex ring. Without the flex ring you now have rivets being hammered on the weight basket. In time the rivets shear off and now we have a run away engine. Simple repair just got bigger. Fix it now while the problem isnt expensive or major. Al

thepumpguysc · Oct 26, 2016

Its no mystery.. Al is right on w/ his advice and price.
IF you want to be sure.. run it without the checkball connector.
Al, do you offer your customers the EID option.?

Billy Shafer · Oct 26, 2016

I have seen those coffee grounds many times over the years.Do as AL says. Take the pump off and get it fixed. Before you have real problems.

Al Baker(pumpman) · Oct 26, 2016

I am pretty much old school. Mechanical pumps and old fashioned service. NO EID , but Do ASAP. Al

Al Baker(pumpman) · Oct 26, 2016

Sorry, just joking about the EID. I use the old school way of thinking. If a machine is 30, maybe 50 years old and needs a reseal, I figure a new flex ring and reseal will outlast The owner. It took X number of years to go bad,should last close to the same length resealed. Not sure If the EID cost are worth it. I try to keep costs down so a pump job doesn't get out of hand. The Stanadyne pumps used in the early diesel autos gave the flex ring a bad name. They just didnt hold up. I have seen 50 year old pumps show up here needing their first reseal. If they can last that long in a 4010 than they cant be all bad. Al

JHesler · Oct 26, 2016

Exactly correct Al, coffee grounds under the timing window. I didn't start it again. Pulled the pump today and will rebuild it. I do understand about pressure differential on the plungers, I just didn't see anything clogging up the return line. Thanks much for your help. John

Diesel mystery

JHesler

New User

01gentdc

Well-known Member

Philip d

Well-known Member

tim s

Well-known Member

01gentdc

Well-known Member

JHesler

New User

Dieseltech

Well-known Member

Rons b

Member

Determined

Well-known Member

JHesler

New User

JHesler

New User

Al Baker(pumpman)

Member

JHesler

New User

Al Baker(pumpman)

Member

thepumpguysc

Member

Billy Shafer

Well-known Member

Al Baker(pumpman)

Member

Al Baker(pumpman)

Member

JHesler

New User

Similar threads