Jinma 254 Injector pump

Kooosh · May 29, 2019

Having trouble getting my Jinma 254 to run properly. It will start but won't idle. Have read quite a few threads and it appears my shut-off lever/rod is stuck. I've attached an image of my IP. Pulling on the "pull to stop" does not do anything and there is little movement on the arm which is on the injector pump. More research indicated that I can remove the cover on the back of the IP and free/clean the rod and then add fresh oil. Is the cover that the dipstick goes into the one that needs to be removed?

And when refilling with fresh oil, how do I know how much to put in or should I just check by using the dipstick?

Lastly, that lever on the back of the motor, should it be connected to anything?

Thanks!

thepumpguysc · May 30, 2019

Will the engine shut off by moving the lever BY HAND.?? if yes, the problem is w/ the cable..
Yes, check/add engine oil to the proper amount indicated by the dip stick.. start w/ 2oz & go from there..

thepumpguysc · May 30, 2019

Looking at the last pic.. there looks to be a LOW IDLE SCREW.. Just turn the screw..
Have a look at your throttle lever.. move it by hand w/ the engine NOT RUNNING & SEE how it works..
There should be a ledge/bump-out that the screws hit on.. pull it to wide open & see what the screw hits on the lever..
Now do the same for low idle.. & adjust accordingly..
I've personally have never had my hands on 1.. but they're all/most, licenced from another manuf. that I AM familiar with.. & they work the same..

Turbo · May 30, 2019

what is the lowest rpm it will run before stalling?
the lever on the engine is you decompression lever , if i am not mistaken , make sure it's not on.
the side of your injector , the long lever is the shut off , I would replace the cable since it's not moving the lever, and the small lever is throttle.
I also noticed you primer is leaking, I not sure if your is the type that has to be locked in place.

Kooosh · May 30, 2019

I've just replaced the IP oil as previous owner must have put too much oil in as the oil would come out when removing the IP dipstick...

My gauges aren't functioning well but very low rpms and only for a few seconds. Even moving the shut off lever by hand, there is minimal movement. How much play should there be?

Yes, my primer is the type where you screw it out and it pops out. When priming, should fuel come out of it?

Thanks for all the help so far, this is my first diesel tractor and still learning everything about it.

Turbo · May 30, 2019

you should be able to shut off the fuel by hand, unless you cable so stiff for it to move. cut the cable or undo the screw.
make sure the primer lock down and secured , its a source for air ,and one of the symptoms is a bad idle .

Kooosh · Jun 7, 2019

Okay, still not running..

I've undone the cable screw for the shut-off lever and it has full function now.

- changed the IP oil
- Cleaned the fuel sediment bowl

What should I try next?

thepumpguysc · Jun 7, 2019

Have u checked the banjo bolt connectors on the supply pump for debris..??
It looks as tho they may have filter screens in them.?? IF SO, they may be clogged..
Just unscrew the bolt connector UNDER the hand primer & check & see if it has a filter screen..

RonMar · Jun 7, 2019

Yep, check where thepumpguy indicated. You should also get fuel flowing freely from there when you open the tank sediment bowl valve. If you have this, re-install the banjo bolt and unscrew the primer handle(spring should pop it up) the other hose runs up to the fuel filter, then runs back to the injector pump. On top of the fuel filter you should find a bolt. Loosen it and pump the primer plunger untill you get only fuel out then tighten the bolt.

There should be another bleeder port on the injector pump. If you have a wider shot of the IP, we might be able to help you find it as your pump is different than mine. The bleeder on mine is a bolt with a ring thru it. You need to open that and pump the primer some more to push any air from the filter to the IP and out that vent. Once you just get fuel out that vent, close it and compress and screw in the plunger handle.

Next take a wrench and loosen the fittings where the hard pipes connect to the injectors. Now set throttle to midrange and crank the engine till you get only fuel out of the hard lines. This will force any air out of the hard lines. If there is any air in the hardlines the injectors will not fire as the air prevents the line from building enough pressure to fire the injectors. Once you get only fuel, tighten the hardline fittings you loosened and see if it will start/run. If you didn't get any fuel coming out of the loosened fittings while cranking try more throttle. If you still don't get fuel out at the fittings you may have an IP issue inside the governor where that fuel cut lever attaches.

Basically the throttle pushes on a spring which pushes the fuel rack open(more fuel). The governor flyweights as they spin push against that spring and try and close the fuel rack. When the two forces balance the engine runs at a stable RPM. That shutoff lever overrides the spring/governor and closes the rack all the way...

thepumpguysc · Jun 8, 2019

WELL SAID, Ron..

Kooosh · Aug 24, 2019

Sorry for the belated reply.

Finally had some time to work on the tractor today. I have unscrewed the supply line from the fuel tank to the injector pump and have taken the little filter out and cleaned it. Fuel is flowing freely from the sediment bowl valve. When I unscrew and pump the primer, I can hear fuel squirting back into the fuel tank via the return line.

Today I loosened the 3 fittings that connect to the injectors and watched for fuel as I cranked the engine. Fuel was only coming out of the third hardline (closest one to the fuel tank). The other 2 hardlines weren't showing any signs of fuel? I then undid the line that's on top of the injectors that connects to each injector and primed using the primer and heaps of fuel squirts out. So it seems there is an issue with the first and second hardline?? Any ideas? Should I completely remove both 1 and 2 hardlines and clean/blow out with compressed air?

RonMar · Aug 24, 2019

Do you have a fuel bleeder port on the injector pump? I looked at your pics, but they are too close-up. It could be that you have an air pocket in the injector pump and you are basically pushing fuel with the primer around the air pocket and back thru the return line to the tank. If you can post a pic that shows the entire IP, I may be able to point it out to you.

Next, on top of the IP where the hard lines attach, under each fitting is a small check valve. If those check valves are not sealing, the fuel goes back and forth in the line instead of advancing up the line one step for each pump stroke...

Kooosh · Aug 24, 2019

Hi Ron,

I've attached some pictures of where I assume the bleeder is on the injector pump. Is it the bolt with the groove through it? Can I just bleed the injector pump through that bleeder by opening it up, pumping the primer and then tightening it back up?

And I also read to bleed from the top of the fuel filter but mine doesn't seem to have the 10mm bleed point?

I will check those check valves out. I couldn't see any fuel escaping through them

thepumpguysc · Aug 25, 2019

The bleeder screw IS that 10mm screw in pic #3..
The hose IN FRONT of the inj. pump is the INLET.. The hose that goes across the bleed screw is the RETURN fuel.
I don't recommend tearing into the inj. pump.. those "top nuts" HAVE TO BE TORQUED back down..

RonMar · Aug 27, 2019

yep, that is the bleeder with the slotted head. yes, loosen it and pump the primer to purge air. You can loosen the hose connection banjo fittings/bolts at the fuel filter to purge air from the filter housing.

The fitting I was referring to above is the ferrule nut around the hard injector line that attaches the line to the fitting on the top of the pump... I am sure they have a torque spec(everything does) but I have never torqued one, just re-attach snug, same as the banjo fitting on the other end where it attaches to the injector...

Kooosh · Nov 1, 2019

Still havent been able to get her started.. Have bled air out multiple times and still nothing. So 2 out of 3 injector fuel lines still aren't getting fuel. When I loosen the the nut, crank no fuel comes out.

After reading some more threads on here, I came across a post mentioning the "fuel rack/governor" could be an issue with not starting. How do I know if the governor or rack it in the correct position?

thepumpguysc · Nov 1, 2019

If u only have fuel coming out of 1 port on the inj. pump & u have GOOD flow TO the inj. pump..
ITS THE INJ. PUMP..
& its not something u wanna mess with.. its time to call someone..

jacques54 · Nov 1, 2019

Like thepumpguy mean by GOOD FLOW FROM TANK, remove the banjo bolt off the hand pump hose that come from the tank (there is a mesh filtrer IN that bolt). Let it flow in a pail, it should flow freely, not dripping?
Out of the hand pump, when you pump fuel come out from bleeding screw with pressure and with no air?
To see fuel coming out of hard lines at the injectors,you must crank the engine to see little drops coming out. (Only few cc per stroke), normal?
Did the oil in pump ever be changed?
Lot of questions but long distance diagnostic is not easy.
Jacques