M7040 no power to glow plugs

[Bgblock427]

Just rebuilt the engine in this tractor and cannot get the engine to start. Primed the fuel system per the wsm and engine turns over fine. tested the power to the glow plugs and no power turning the ignition switch. removed and tested the relay and its working fine when bench testing. There is power applied to the relay but its not switching when its installed in the tractor. Is there supposed to be a dash light on this model tractor? if so its not coming on. I have been using the schematic in the wsm. any thoughts what may be not working.

 

[Russell King]

Replace relay??

 

[North Idaho Wolfman]

There is 2 power feeds to the Relay, make sure it has both.

 

[JasonW]

There is a dash light but I believe it only comes on below 32F. Did you bleed the fuel lines at the injectors? It shouldn’t be that cold in TN right now to need glow plugs

I can manually activate the glow plugs on my M6040 buy turning the key in the start position while the shuttle shifter is on F or R. The dash light does not illuminate although I have verified power at the glow plugs with this method.

EDIT. Assuming the neutral switch is functional, to prevent the engine from turning over.

 

[Bgblock427]

Replace relay??

No I just removed it and tested it and put it back in

 

[Bgblock427]

There is 2 power feeds to the Relay, make sure it has both.

It does, we found the blue wire has been spliced in the past and fixed it properly. Thats the one that goes from the relay to under the dash.

 

[Bgblock427]

There is a dash light but I believe it only comes on below 32F. Did you bleed the fuel lines at the injectors? It shouldn’t be that cold in TN right now to need glow plugs (i did not bleed all way to injectors just the pump on top of fuel filter as wsm says)

I can manually activate the glow plugs on my M6040 buy turning the key in the start position while the shuttle shifter is on F or R. The dash light does not illuminate although I have verified power at the glow plugs with this method.

EDIT. Assuming the neutral switch is functional, to prevent the engine from turning over. yes