D722

[kubotafreak]

No, I disassembled the the pump it’s all fine, just carbon deposits on some of the parts, but the plunger, spring etc are all good

that rust on the inside of the case worries me though

What does the area above the head look like?(valves, springs rockers)
Under side of piston cylinders would be the worst place. Otherwise i wouldnt be too concerned, most of the fuzzy rust wipes off from the windage. Most abuse will be on the oil pump. Now if it is large flakes like the thing got submerged, then you have cause for concern.

 

[Gdubs]

I will pull the valve cover off today and check out that upper area. As for below pistons, if I need to check that I assume I’m just pulling oil pan and shining a light up there?

 

[Gdubs]

I will pull the valve cover off today and check out that upper area. As for below pistons, if I need to check that I assume I’m just pulling oil pan and shining a light up there?

Rocker arms etc all look good

I took an injector pump from a d902 that I know was working before it was pulled from that motor, and installed it on the d722.

The same problem occurs. Starts and runs rough, grayish smoke, when I crack injectors 1 and 2, fuel runs out and it starts to sputter, with injector 3, high pressure fuel shoots straight up at me still, amd smoking stops.

the only thing I can think now is timing or cam issues?

 

[kubotafreak]

Rocker arms etc all look good

I took an injector pump from a d902 that I know was working before it was pulled from that motor, and installed it on the d722.

The same problem occurs. Starts and runs rough, grayish smoke, when I crack injectors 1 and 2, fuel runs out and it starts to sputter, with injector 3, high pressure fuel shoots straight up at me still, amd smoking stops.

the only thing I can think now is timing or cam issues?

The cam is visible with the pump removed. Will be obvious if it is scored or flat. You need to check the line itself for rust(restriction-kink-bend).

 

[lugbolt]

It dawned on me this morning to recheck the fuel return lines, I indeed had them routing right into each other hence to return to tank. Changed that and it fired up, but still Smokey

I cracked each injector and #3 started spraying fuel straight up (not the typical dribble from the top of nut) and no change in idle, but the smoke stopped. When I re tightened it, the smoke started again.

I switched that injector out with what I presumed to be a good injector from my d902, (same kubota part number) same spray, same smoke.

could it be two bad injectors? Or cylinder issues causing injector to spray back at me when cracked?

you have smoke on #3. So you have fuel. But no running, that's why it's smoking on #3, ain't running. I'd suggest a compression test at this point.