D7E Governer

Units 48A2809-up have a speed limiting plunger that blocks the governor linkage until sufficient engine oil pressure is achieved. What do you have for oil pressure?

The oil pressure guage pegs the needle when cold and and is in the upper 2/3 of the operating range when warmed up at low idle. The engine only has about 100 hours on an inframe, new rod bearings and lower half mains. The tractor has sat about 2 years since it was used much. I changed the oil before I started to use it last week. I've asked around and some have referred to the plunger you speak of where is it, and can I clean it? Not having a service manual I don't want to just start taking stuff apart.
Thanks for your time and reply. Rocky

Hi 1arock,
as OM suggested it seems your oil pressure is dropping too low when the engine oil is at operating temperature.
Minimum oil pressure at Low Idle is 10 PSI and the maximum at High Idle would be around 45 PSI +- 20%
I suggest you obtain and fit an oil pressure gauge of known accuracy and get back to us with a true oil pressure figure.
As the engine has recently been overhauled I would suspect that the oil pump pressure relief valve is stuck partly open with crud.
Some where I have a break down of the Cat oil pressure gauge pressure to peg the gauge and the different sectors of the dial.
I will post it when found so you can check your gauge.
Hope this helps.
Cheers,
Eddie B.

Unfortunately the plunger valve is located on the back side of the governor housing requiring governor removal to access. It is located right next to the control lever. I looked through my stuff but can't find a spec for what minimum pressure is required. The 5M1065 oil pressure gauge is a 0 - 40psig unit.

I don't think low oil pressure is the issue. After looking at the guage again, it reads low idle in the middle of it's sweep, and even when warm it never gets into the lower half of it's range. I overhauled the engine when it lost a valve seat. It has much more oil pressure now than before. It is the cat factory instrument and I have no reason to suspect that the guage is at fault. I can however understand that there may be trash in this valve as I did the inframe in the field. I guess I need someone to post the service procedure to remove and reinstall the governer housing or whatever it takes to clean this valve .
Thanks for the help, Rocky

The plunger valve is fed from an internal oil passage coming from the main engine. Should be checked/cleaned. That's the valve shown in Section A-A.

To remove the injection pump the oil filter case assembly requires removal. Remove the pump side cover and disconnect the rack.

When installing be sure to change the fuel passage o-ring and align the off center tang on the pump shaft with the off-center groove in the fuel injection pump camshaft.

Thanks for the help. I'll let you know how it turns out. Rocky

Rocky, a warning light just came on here. Recent inframe and now low oil pressure symptoms.
That old engine has many 1/8"NPT plugs in it all over the place to plug off lube passage drillings.
These plugs are handy for checking that oil is getting to all the places it needs to.
I think you should get hoses into as many of these plugs as you can and check the pressures at low idle with warm oil. Write down and compare all findings. You might have a plugged passage somewhere or a problem with the piping inside of the engine.
Later Bob