My Jimna's not Jimin

[Wilson6Ranch]

Can anyone help me? My Jimna 204 , TY290 has a fuel problem. I just installed a brand new fuel injection pump that I bought from Tommy at Affordable Tractors and I am able to get the engine running. My problem is that the engine will idle on both injectors and while increasing the RPM's one of the high pressure fuel lines gets air and the RPM's decrease with the throttle wide open. I bleed that line and the other line will do the same. This causes only one piston to receive fuel and lopes the engine. When I get both lines air free and running good I take it for a spin and it starts getting sluggish and I barely make it back to the barn. I have checked all banjo type fittings and high pressure fuel line fittings for tightness and it still continues to get air in the lines. Any Ideas?

 

[RonMar]

Can anyone help me? My Jimna 204 , TY290 has a fuel problem. I just installed a brand new fuel injection pump that I bought from Tommy at Affordable Tractors and I am able to get the engine running. My problem is that the engine will idle on both injectors and while increasing the RPM's one of the high pressure fuel lines gets air and the RPM's decrease with the throttle wide open. I bleed that line and the other line will do the same. This causes only one piston to receive fuel and lopes the engine. When I get both lines air free and running good I take it for a spin and it starts getting sluggish and I barely make it back to the barn. I have checked all banjo type fittings and high pressure fuel line fittings for tightness and it still continues to get air in the lines. Any Ideas?

I would say start at the fuel tank outlet fitting(drain tank and remove for visual inspection) and go completely thru the system(hand over hand the lines from fitting to fitting) looking for restrictions and making sure all the air is out of the supply line and fuel filter. There are strainer screens at some points that could be fouled with rust scale, dirt or anything growing in the fuel and restricting fuel flow.

Restricted flow could be causing some part of the system feeding the injector pump to come under vacume as the pump draws and compresses the fuel for injection. If this is happening, the slightest pinhole can be allowing air to be drawn into the system. If the fuel was flowing correctly, this type leak might not be a problem and might only show as a damp spot on a hose or around a fitting as it is only under the slight pressure from the weight of the fuel in the tank. Put some restriction on the ruel supply and allow the pump to draw a little vacume(which would increase with throttle position increase and engine RPM) on the supply line and you could be drawing in enough air to foul things up.

Why did you have to swap out the injector pump?

 

[Soundguy]

Anyone else seeing a connection here.. IE a fuels system issue that was not solved by a parts swap?

Soundguy

 

[greg_g]

Anyone else seeing a connection here.. IE a fuels system issue that was not solved by a parts swap?

Soundguy

Not yet. I'm initially inclined towards pump timing. As I'm sure you already know, one can't just bolt on a replacement mechanical injection pump and assume that fuel delivery will be properly timed.

And I too would be interested in knowing for what reason the original pump was replaced.

//greg//

 

[schmalts]

someplace you have a leak or a restriction, or a restriction causeing a leak (vaccume leak) , check your shut off valve. Close it completely and reopen it when it starts running sluggish and when you re-open it watch to see if any sediment enters the sediment bowl. When the engine gets sluggish check your fuel sediment bowl for bubbles or foaming. With the tractor not running undo a line closest to the pump and let it free flow to see if you have a good amount of free flowing fuel. If not, work your way back until you find the restiction. I don't think fuel pump timing has nothing to do with air in the lines at all.

 

[DOUBLEG]

The problems I have had with the fuel system all stemmed from dirt and paint clogging the in-line screens. The tractor would run ok and then loss power, once enough fuel got through it would run ok again.

 

[Soundguy]

So why did you change the injector pump?

Soundguy

 

[bjr]

I agree with Schmalts. A plugged line somewhere. I have real issues with Jinma's fuel tank shut off valve. The holes in the valve gasket that align when rotate on on position are microscopic size at best. I replaced the valve with a generic one quarter inch needle valve from a hydraulic hose fitting place. Had a new fitting put on the hose to go to one quarter inch pipe. Best modification that I've done to the tractor. I've never had a starting or power issue. The Jinma fuel tank strainer valve combination was replaced immediatly when I got to assemble the JM354 crate tractor. bjr

 

[Wilson6Ranch]

Hey Guys, Thanks for all the suggestions, I got my girl back to the fields. As for an answer to your questions. My Father-in-law had looked at the tractor and told my that my injector pump was not working properly and was to weak to pump. So, I bought a new one and after installation I was finally able to get it started, but the problem I wrote you guys about began and that was when I checked the lines, timing, and all fittings. I decided to buy all new lines, seal washers and a sediment bowl. My girl started right up and off to the fields we went. While out there, I noticed she was starting to over heat and I took her back to the barn where I found a leaking water pump that was also wobbling (bad bearing). I bought a new pump and back to the fields we went and she ran great all day long. Once again THANKS!!