Jinma 254 Help, Can't keep it running !!!!!

[Raw Bone]

OK guys, I知 at my wits end. I致e replaced my injector pump on my Jinma 254 and that seems to have cured the problem of not firing on the #1 cylinder. I致e got the timing right and I can start it at will, however when it starts I can feed the throttle to it solely and bring it up to 1800 or 2000 rpm痴 but within about 4 5 seconds the rpm痴 will drop off and drop back down to about 500 rpm痴 but it doesn稚 die. It acts as though it is starving for fuel. I致e got good fuel flow from the tank down to the delivery pump and up to the new spin-on fuel filter. From the spin-on filter to the inlet side of the injector seems to have fuel also. I知 basing this on the fact when I break the bango fitting loose at the inlet side of the injector pump after it has been running I get a good spray of fuel around that fitting. I致e been told that it may have air bubbles trapped between the I/P and the injectors themselves. But it seems that after running on its own for approx. 1 1.5 minutes that any air in the lines would have been purged out through regular fuel travel through the system. I haven't figured out how to keep it running long enough to crack the fittings loose at each injector to bleed out any trapped air, that is if there is any. Any suggestions would be greatly appreciated.

Thank You,
Raw Bone

 

[robert421960]

i ran mine out of fuel laterly
when i got it running like you are saying i loosened all my injector lines left them tight till running then loosened them one at a time till it bled the air out

 

[Red55]

RawBone,
More information will help with diagnosing your problem. Specially what year your Jinma is and your location. There have been problems with the fuel lines collapsing internally. Of course you can also have a diesel bug problem where one of the internal screens are getting restricted. -Ed

 

[greg_g]

I haven't figured out how to keep it running long enough to crack the fittings loose

Understandable, because the tractor won't run on air. You have to purge the lines before the tractor will start/run. Loosen each of the hex collars at the injector slightly, just enough for them to leak. Put the tractor in neutral, set the brakes, hand throttle to full. Crank the engine. Bubbles will form around the collars, that's air escaping. When the bubbles turn to fuel flow, tighten the collar. You're still cranking the starter during all this. I've started an engine after tightening the first collar. When that happens, release the keyswitch. Continue watching the other lines, tightening the collars as the bubbles turn to fuel flow.

//greg//

 

[Diamondpilot]

Have you check the air filter also? Could have a mouse nest or just a dirty air filter and its starving for air. Basically I am saying all the simple stuff also. I like to get a second set of eyes on things. I have a couple of good neighbors that see things I miss from time to time and I do the same for them.

Chris

 

[Affordable]

When you pump the primer on the fuel injector pump does it get hard to push ? If so you may have the banjo bolt with the check valve in the wrong hole,I have seen this alot of times. Make sure the bolt that holds the fuel line to the front side of the injector pump has this check valve banjo bolt,if it's on the backside of the pump thats your problem, These pumps come shipped with those 2- bolts in the wrong hole all the time, switch the bolts and that will cure your problem,if they are in the right spot I would say it's air in the system,and you should be able to keep pumping the primer as you are bleeding off the air to keep it running


Tommy
Affordable Tractor Sales Co.
" Your Jinma Parts Superstore"
Home of compact Jinma, Foton, and Koyker Tractors and Parts, Wood Chippers, Backhoes - Affordable Tractor Sales Company

 

[Bob Rooks]

Additionally, if the manual priming pump doesn't get hard to pump, the pressure relief valve in the fuel injection pump fuel cavity (return line to tank) could be stuck open, and also the seats of the check valves that Tommy mentioned could be stuck open or pitted badly - both cases caused by contaminants and/or diesel bugs (corrosion).

 

[Diamondpilot]

I think Tommy hit the nail on the head. I now remember a few others having the same issue.

Another good reason to keep Tommy around.:laughing::laughing::laughing:

Chris

 

[TSMART]

A great lesson I got from Ronald , he advised me to push the injector button so I would know how it should feel when the air was out. I did so and the tractor runs fine!

 

[Bob Rooks]

Question: What is an injector button?



(Y'all knew I'd bite on this :laughing