Help! 284 won't start, throttle problem

[meporsche]

I started the tractor this morning after shutting it down 15 hours ago. As soon as the engine caught, it started racing, with the throttle closed. I managed to pull the fuel cutoff before it got past 1700 rpms. WHen I tried to restart it, no fuel to the cylinders. Just spins over. I threw a little ether into the air cleaner to make sure the internals were OK and it caught and ran for a second or two.

I'm guessing something on the fuel cutoff broke inside? What the devil would break while it was sitting overnight to make the throttle control fail?

I'm sitting here with 8 head of cattle and two horses that need round bales and I have no tractor. Any help appreciated.

Thanks,
Darwin[

 

[meporsche]

Update*

After searching the web and these archives, it appears that I had a low oil level in the injector pump. I have refilled the pump but no success. I have looked again through both manuals, I see no clues about keeping this pump full. I, like others apparently, thought this was fed by the engine oil.

I am relunctant to remove the pump because of re-timing problems.

I am also wndering why I cannot get fuel to the cylinders by using the priming piston on the pump.

Can anyone help? I just had to roll a 900# round bale uphill 20 yards into the pasture.

Darwin

 

[Diamondpilot]

Like you said a lack of maintenance led to a injector pump failure of some type. Your only option at this time is to remove the pump and replace. Since its already toast you may try marking everything and taking it off, tearing it down, and take a look to see if its something you can clean up and or un-seize.

Chris

 

[meporsche]

I'm not so sure. After I topped up the oil, I decided to go ahead and drain the pump to see what the oil looked like. I drained out about 20-24 oz, I had only added about 8. Doesn't seem like enough of a shortage to cause terminal failure.

I am going to try and fill the tank to see if I can gravity bleed the high pressure lines. I have lots of fuel on the low pressure hoses but nothing on the high side.

And after reading some stories of others, I am worried about installing a new pump and not being able to set the timing. If I set the engine to TDC and pull the pump, I'm not sure I would know how to line up the gearing on the new pump.

The manuals I have are a joke. And the inj pump in my parts manual doesn't even remotely resemble the one on the tractor. And going over both manuals, plus the dealer maintenance schedule, there is nothing, anywhere about inj pump maint. or service.

This tractor only has 56 hours on the clock.

 

[RonMar]

Check your throttle and shutdown linkages carefully. I have noticed that the two can interfere if the shutoff is pulled with throttle applied. Your shutoff may not have fully disengaged after the panic shutdown. The initial runaway may have been caused by your foot. I know i have done this inadvertently.

Not being able to get fuel to the injectors using the hand prime pump sounds normal to me. The injector pump pistons have inlet ports that close off the supply of fuel as the piston starts to build hydro pressure to send to and pop/fire it's injector. I would expect only one to be open at any given time. There is also probably a spring loaded check valve at the top of each pump cylinder that would further restrict flow. The hand prime pump is designed to get fuel thru the filter to the IP's feed pump and pump body. You really need to crank the engine with the injector fittings loosened to prime the high pressure lines. But this only works if the throttle and fuel cut are positioned to allow flow to the injectors.

On your IP body there should be a ring thru the head of a screw. If you loosen this screw and pump the hand primer pump and fuel comes out, that pump has done it's job IMO.

 

[Affordable]

What it sounds like is a stuck piston in the injector pump,they are small discs with a spring under them,one is stuck open thats why you cannot get the primer to pump fuel,the springs are under the head(where the hardlines connect) I don't recommend you messing with the injector pump thats up to you,if you remove the 4-bolts holding the head on you will see the springs and discs

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

 

[doxford jim]

What it sounds like is a stuck piston in the injector pump,they are small discs with a spring under them,one is stuck open thats why you cannot get the primer to pump fuel,the springs are under the head(where the hardlines connect) I don't recommend you messing with the injector pump thats up to you,if you remove the 4-bolts holding the head on you will see the springs and discs

The small discs are in fact, check valves and they close at the end of the stroke of the pump plunger, to prevent pressure bleed down of the high pressure fuel to the injectors.

These fuel pumps have a governor attached and these regulate the fuel at full open. If these governors stick, symptoms similar to what you experienced, will occur. Flushing the governor mechanism and draining will often remedy the stickiness of the governor. Drain the existing oil out and refill with diesel fuel. run the engine for several minutes, stop it and the drain the oil again. You should see the dark coloured crap start to come out. Refill and rerun again - doing this maybe three or four times until the diesel fuel colour doesn't change too much. Then drain and refill with the appropriate lube oil.

Chances are this is your problem - but no guarantee. Still, give it a go and see what happens. Please report back so we can all learn a little.

Good luck

Jim

 

[meporsche]

OK Jim, I'm going to give it a shot. I can't run the engine of course but I am hoping I can achieve the same effect by turning the engine over for 10 seconds every few minutes or so.

I think that somehow, the governor sticking has mucked up the fuel cutoff. there was a post somewhere on here where the exact same thing happened to another. But the thread turned into an argument over the diff between kero and diesel and the solution was never posted.

I'm going to throw a Kats magnetic heater on it before I drain the pump oil, hopefully that will get more of the oil out before I fill it with diesel.

Thanks,

Darwin

 

[meporsche]

Well, I drained the oil in the IP again, got some more dirty oil out. I filled it with Diesel and turned it over for about an hour. I tried tapping the IP head with a hammer to try and free up the discs but no luck. I opened the drain and the diesel looked as clean as when I put it in. Ready to give up as I have no taste for putting a new IP on and finding out it still won't run.

Maybe I can trade it for a Ford 9n if I offer to throw in cash and my oldest child. But I'll never find anyone that stupid.

 

[Affordable]

Take the top part off the pump, worst case you are going to need a pump anyway,you may get lucky and get to free it up


Tommy
Affordable Tractor Sales

 

[erj]

What were the results of the actions suggested by RonMar in post 5?
RonJ

 

[meporsche]

I'm going to give it a go but luck is not my strong point at this moment.

 

[Diamondpilot]

I'm going to give it a go but luck is not my strong point at this moment.

This type of poor prep of the tractor is what give Chinese tractors bad names. Your dealer did you no favors by selling you a tractor that was not properly prepped or giving you the proper information to service and maintain your investment.

I really hope you can get it going. I know you are frustrated but those old N series tractors can be a nightmare also and have no where near the power or utility your Jinma has. Worst case you will need a new pump and the members here can help you get it on and timed if you have patients.

What about your dealer? Is he any help or out of the picture?

Chris

 

[doxford jim]

Take the top part off the pump, worst case you are going to need a pump anyway,you may get lucky and get to free it up


Tommy
Affordable Tractor Sales

Tommy is right when he says take the top off and look inside at what is happening. These disc/check valves can leak back very easily - all that is needed is avery small piece of rust, dust etc to hold the disc off it's seat. If that is the case, then any high pressure fuel instantly becomes low pressure fuel and that gives no injector operation.

As Tom mentioned - check the obvious first. Worst scenario is you may need a new fuel injection pump. If that is the case we can walk you through the pump installation - it just ain't rocket science, That is one of the beauties of these tractors - they really are fixable by the average owner.

Let us know how you make out - good luck.

Jim

 

[meporsche]

Re: Post #5, no hangups on any linkage or cable. Manual pump pushes fuel through the low pressure lines, past fuel filter.

I couldn't take off the IP head to check the discs, it was raining hard here and the tractor is outside with no way to get it in.

Fortunately a neighbor has agreed to move hay for me so my animals will be OK. Tractors are like Jaguars, you need three so that when the normal two won't work you can drive the third and use the other two for parts.

 

[RonMar]

I don't think the discs/check valves are the problem. I don't see all 3 being hung up at the same time, and if it is only one, the other 2 cylinders should still try to fire. If there is fuel in the IP body and no fuel comes out of loosened injector fittings when you crank the engine over, then I think your problem lies in the fuel control of the governor, as that is it's job to control the rack and ultimately fuel delivery.

The throttle(better term would be speed selector) pushes a spring that pushes the fuel rack open. the fuel rack controls the stroke/volume of the piston pumps which determins how much fuel is delivered. Inside the governor are 6 balls that are spun by a rotating cage assembly. As they spin centrifugal force pushes them outward against a cone. This cone moves a rod that pushes the fuel rack closed. The force applied by the balls to close the rack is proportional to engine RPM, and the force applied by the spring to open the rack is proportional to the throttle position. The balance between these two forces is how the governor maintains a particular RPM for a given throttle position. There are two setscrews at the rear of the governor with safety wire on them that limit the fuel rack travel. The fuel cut lever applies additional force to the rod in the same direction as the spinning balls and cone does to shutdown the engine. I think that is where your problem lies. I think the cone is stuck in the closed rack position(perhaps a ball or part of the cage has failed) or more likley IMO, the fuel cut mechanism is holding the rack in the shutoff position. Since this was the last thing you did, the last time it ran, I would probably look there first as it may have been damaged internally during the aborted start. Tractor Outlet used to have service bulletins online, one of which had a cool pic of a disassembled governor. Unfortunately, I can't find a link or their website anymore...

Just to make sure, the fuel cutoff/shutdown lever(one with the shutdown pullcable atached to it) needs to be all the way forward and touching the main injector pump body for the engine to run.

Knowing what I know, and since none of the injectors are delivering enough fuel to fire the engine, I would look in the rear governor housing first... I believe you can disassemble this housing without removing the injector pump from the tractor, but I have never personally done one of these...

 

[meporsche]

There is a plate on the end of the housing where the throttle lever and fuel cutoff switch in contained. It is somewhat oblong and has two cap screws holding it on. Is this where I can can get to the governor?

If not, it looks like I will have to remove the plate that the oil filter mounts to as there is one screw/bolt under the housing that will not come off unless the plate is removed.

I can post a picture tomorrow of what I am talking about. But your observation makes sense, it does seem unlikely that all three discs would simultaneously stick.

PS I have tried to start it with the fuel cutoff lever in every conceivable position, with every possible combination of fuel control lever.

When I first spin the engine I get light colored smoke then black, sooty exhaust. There is SOME fuel getting in somehow.

 

[meporsche]

This type of poor prep of the tractor is what give Chinese tractors bad names. Your dealer did you no favors by selling you a tractor that was not properly prepped or giving you the proper information to service and maintain your investment.

What about your dealer? Is he any help or out of the picture?

Chris

Dealer is Josef Tractor in Dallas. Pump is under warranty but they have yet to return my call. I have to return the pump before they will send me another. Which may turn out to be the same pump in a different box with new paint or one that doesn't function either. RIght now I have a pump timed to the engine and if I can repair it I would rather than tyr to pull teeth with the "dealer" and put another pump on that won't work. I read in the archives about a peach farmer who spent weeks trying to make a new pump run which turned out to be defective.

 

[biggerten]

Tractor Outlet used to have service bulletins online, one of which had a cool pic of a disassembled governor. Unfortunately, I can't find a link or their website anymore...

I think they're gone, I seem to recall some discussion about them last year.

It's probably not the same pump, but Ron has some pictures of a dis-assembled pump at Jinma Dealer, Wood Chipper , Compact Jinma Tractors

 

[Affordable]

Look in this pic,you will see the 3-springs and seats,if 1-disc is off you will not get pressure to the other cylinders,I have new pumps if you end up needing one and you don't get any help from your dealer.

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