JD X749 Dying after 30-45 minutes

[Mike VS]

Got it, I'll check them.

This is where I'm at... All lines are 100% clear from filter to injector pump. The fuel supply line leading from the injector pump to the tank is gravity flowing at a very strong rate. I have not gone into the tank, but at the rate it's flowing I just cant imagine there is a obstruction.
So I have taken the transfer pump off and see that all connections and nipples are super clean inside. The manual pump works very well and there does not seem to be a problem. So, do I take it apart risking ruining these diaphragms and gaskets? I'm not sure where inside these check valves are but I got to tell you it seems unlikely this is the problem. What do you think?

 

[Mike VS]

Yes... To the injector from the tank. I have not checked the return.
Looking at the pump, I see the diaphragms and can just envision leaks afterwards where there once were none.

 

[Mike VS]

Do you mean to the injector pump from the tank, or is this a return line?

I don't think the transfer pump is a fragile item. I wouldn't hesitate to open it up to check the insides. You're running out of options on this to the point that the injection pump will be all that is remaining.

How about I hook up an electric fuel pump (I have one) and run it with that for a while?

 

[Diggin It]

I may have missed a few things (as usual). Is there a fuel filter at the front in the engine area? Is it clear plastic you can see through? If so, have you checked to see if there is fuel in it when the engine stalls?

 

[Mike VS]

I may have missed a few things (as usual). Is there a fuel filter at the front in the engine area? Is it clear plastic you can see through? If so, have you checked to see if there is fuel in it when the engine stalls?

Yea, you got to go back and read. We are way further than that.

 

[Mike VS]

It's worth a try. I might even consider bypassing the filter and go from the tank right into the injection pump.

That would also bypass the return line. I'm worried this electric pump might be too much without it.

 

[Myz28u]

Just an idea, but when I worked for a Deere dealer we used to see the fuel line from the tank get pinched between the fender deck and top of the tank. It wouldn’t be completely pinched shut but it would be enough that it run for a bit and then sputter and shut down. Pretty easy to remove the fender deck from what I remember. Unless they changed something.

 

[Mike VS]

Just an idea, but when I worked for a Deere dealer we used to see the fuel line from the tank get pinched between the fender deck and top of the tank. It wouldn稚 be completely pinched shut but it would be enough that it run for a bit and then sputter and shut down. Pretty easy to remove the fender deck from what I remember. Unless they changed something.

As I said earlier, the fuel flows very fast by gravity when I disconnected the supply line, but maybe I'll try the flow test while sitting on the seat.

 

[Egon]

Any chance there is a line that gets soft when heated and collapses under vacuum? This could also apply to the air intake system.

 

[Mike VS]

Any chance there is a line that gets soft when heated and collapses under vacuum? This could also apply to the air intake system.

I can't say for sure but I don't think so. This is a tractor with low hours and everything inside and out appears as new. All hoses are in very good shape and clean. At this point I'm pretty sure it's a fuel starvation issue and not air intake which is also like new.