Help Needed: Bleeding MX5100 Fuel Filter

[JC-jetro]

EXCELLENT post JC. This gentleman's transfer pump or lift pump is air locked, simply pull the line off the transfer pump (top photo) that goes to the injection pump and draw a slight vacuum on the line allowing the air bubbles to clear up, THEN start the engine with the bleeder valve open.

Fred

That's right Fred. I was not able to find a detail of the transfer pump but it has to be a diaphragm operated pump that is driven by a cam of some sort. pretty much like old mechanical fuel pump on vintage American vehicles driven by cam or crankshaft combination. A hand operated Mini vacuum system like "mityvac" will be all it needs to draw the fuel thru the transfer pump. Since the fuel tank is atmospheric and the transfer pump is below the level of fuel, just taking the discharge hose on the transfer pump might be enough. I suppose one also can use a 2 foot section of clear tubing and try to siphon by mouth and watch the level of fuel in the tubing.

JC,

 

[rayclar]

If your fuel filter bowl filled 1/2 way then stopped you might have some dirt somewhere between the tank and fuel filter?

 

[Chilly807]

I think part of the problem may have been screwing the filter bowl on too quickly. On my L3400, there is a valve in the rim of the fuel filter mount that shuts off when you remove the bowl to prevent spillage. Once you've replaced the element, screw the bowl on until fuel begins to fill the bowl, once it's full and starts dripping over the top, screw it on the rest of the way. This will fill the filter completely and it's less likely to air lock. The MX5100 may be different?

The injector nuts are accessible, but a PIA to get to.. no one said it was going to be easy

Sean

 

[PHILLIP G]

I have a mx5000, I always fill filter with fuel when re- installing to cut down on air in system. Always starts right up.

 

[PHILLIP G]

From my experience it would help to first make sure filter is full of fuel, make sure line from filter to injector pump is purged of air. Will need to take line loose at pump to release air from line, should be fuel with no air bubbles. If that doesn't get it going, you could loosen injector lines at pump to purge air from pump, will have to turn engine over to do this. When fuel only comes out, tighten line. You may have to repeat on other injector lines. Use caution when loosening injector lines, if fitting doesn't swivel on line, the line could break.

 

[sixdogs]

Fill the tank with fuel. Kubotas like this need a full tank on a fuel filter change and I'm near certain the MX5100 owner's manual details it. This should solve the problem unless the partial tank compounded the issue. Problem should be solved.

 

[Tx Jim]

Fill the tank with fuel. Kubotas like this need a full tank on a fuel filter change and I'm near certain the MX5100 owner's manual details it. This should solve the problem unless the partial tank compounded the issue. Problem should be solved.

Not just Kubota's like their fuel tank FULL on fuel filter change but all tractors I've worked on are easier to bleed fuel system with a full tank.

 

[sixdogs]

Not just Kubota's like their fuel tank FULL on fuel filter change but all tractors I've worked on are easier to bleed fuel system with a full tank.

Agreed.
Also, I have owned a number of tractors over the years and what works for me on a fuel filter change is first to run the tractor until it's fully warmed up from use. Then I immediately change the filter, fill the canister with fuel and try to start it. It almost every case it starts and I often avoid the need to bleed the fuel system. Beat me but it seems to work except sometimes on my John Deere 5520.

 

[Chilly807]

I was expecting to have to bleed the system when I changed my fuel filter, but I just made sure the bowl was full and it never missed a beat after starting.

Sean

 

[Tx Jim]

My Kubota M7040 is one of the easiest tractors I've owned to change fuel filter and not have much trouble getting re-started.