M7040

[Stevelippe]

I have an M7040 that I maintain and it has a problem with the return system. Every once in a while the hose off injection pump blows from too much pressure. I know the return system doesn't have more than fuel pump pressure. Any one else having this problem. My concern is that there is some high pressure leakage from injection pump causing problem. Not sure how to test.

 

[North Idaho Wolfman]

I have an M7040 that I maintain and it has a problem with the return system. Every once in a while the hose off injection pump blows from too much pressure. I know the return system doesn't have more than fuel pump pressure. Any one else having this problem. My concern is that there is some high pressure leakage from injection pump causing problem. Not sure how to test.

It's more likely that it's got a clogged return line or fitting on the fuel tank or a clogged vent on the tank will also cause issues.

 

[Tx Jim]

Welcome to OTT
I once during cold weather experienced the fuel return line separate at connector on my '11 M7040. I rejoined the hoses & it's been fine every since. The fuel return line on my M7040 has a "round check valve" installed that I don't see in parts schematics

 

[North Idaho Wolfman]

Tx Jim, you are exactly right, I forgot to include the check valves too as a point of blockage.

 

[Tx Jim]

NIW
Can you please explain the need for check valve in fuel return line on a Kubota? I've never noticed a check valve on fuel return line on any other brand tractor I've been associated with. I know my JD & Ford tractors don't have a similar type check valve on return line.
Thanks,Jim