JD 755 losing prime

[ibboatin28]

My 755 needs primed before it will start. It ran fine all summer but now it needs bled at the injectors before it will start. No work has been performed on it since mowing other than removing the mower. Any suggestions as to where to start looking?

 

[Tx Jim]

In lieu of bleeding at injectors have you tried just bleeding at fuel filter?? Have you considered adding a check valve to keep fuel from draining back to tank?? I would open bleed screw(parts key #27) turn ign switch on to activate elect fuel pump when air bubbles stopped coming out tighten screw and attempt to crank engine

 

[ibboatin28]

In lieu of bleeding at injectors have you tried just bleeding at fuel filter?? Have you considered adding a check valve to keep fuel from draining back to tank?? I would open bleed screw(parts key #27) turn ign switch on to activate elect fuel pump when air bubbles stopped coming out tighten screw and attempt to crank engine

Yes I bled the complete system. It's just odd that it ran fine till I parked it and now have a problem. I'm going to top off the fuel to be see if that helps. I've ran it off and on about every week this fall with no problem. An inline check valve might be in order. Any suggestions on that component? It it something that would be available at the local AP store?

TIA

 

[JimRB]

Wouldn't the fuel pump be the check valve?
Does it have a new fuel filter?
Have you removed the fuel pick in the tank to see that the tank is clean and the fuel pickup is not clogged?
Maybe this diagram explains more if the link even works. John Deere - Parts Catalog
Grasping at a few straws here.

 

[Tx Jim]

An inline check valve might be in order. Any suggestions on that component? It it something that would be available at the local AP store?TIA

Here's what popped up from a Google search

 

[ibboatin28]

I would think the fuel shut off valve would contain the fuel in the lines. Perhaps it has a piece of ice in it. I've not been into the fuel system since spring so I don't think it's there. I'm going to top it off with fuel and run it today to see if that helps. It seems that if it's related to just the cold weather perhaps I have some ice somewhere.

Thanks for all the advise

 

[ibboatin28]

Update on this problem. I installed an inline check valve this spring. The tractor started with no problems all summer. As soon as it gets cold and the tractor sits for a week or so it seems to lose prime at the injectors like it was run out of fuel. It only does this when it gets cold. Any other suggestions?

 

[Azmotorhead]

Only thing I can think is happening is the fuel injectors are leaking the fuel into the cylinders. Your Inj pump is below the fuel tank,so its gravity fed. Injectors are above the Inj pump so fuel will only flow back if there is a leak(bad valve) in the pump,but still it will be stopped by pressure from fuel in tank.
Are you getting fuel into your Cold start reservoir above the injectors?
When you energize your key, if the cold start valve is working properly. fuel should dribble from the reservior directly into the intake manifold.

 

[ibboatin28]

I have not checked the cold start reservoir. It's just odd it only does it when it's cold. It ran fine all summer. It acts just like it was run out of fuel.

 

[Tx Jim]

Only thing I can think is happening is the fuel injectors are leaking the fuel into the cylinders.

I think if injectors were the problem this would come near happening in warm weather instead of cold weather. I suppose one could pull injectors and have them tested.