M7040 no power to glow plugs

Bgblock427

New member

Equipment
M7040, L4240 and ZD1211
Jun 21, 2024
20
4
3
Tennessee
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.
 

JasonW

Active member
Jan 29, 2015
380
189
43
Al
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

New member

Equipment
M7040, L4240 and ZD1211
Jun 21, 2024
20
4
3
Tennessee
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