Rough Running Ford 1720

[RBC]

I have a 1988 3 cylinder diesel Ford 1720. It starts in seconds and runs great the first 15 to 30 minutes. The RPM's then drop off sharpley and fluctuates up and down barely running, limping back to the barn. I have changed the fuel filter and bled the lines making sure there is nothing plugged or leaking. Any help would be appreciated.

 

[Hooked_on_HP]

Loosen the fuel cap and see if this helps. The vent can get pluged. When it starts acting up disconect the fuel line and see if you are getting a good flow of fuel. Things can end up in the tank that can cover the outlet. Your problem seems fuel related.
Bill

 

[RBC]

Thanks for the advice but quickly found another issue. While checking my oil dipstick I found diesel mixed in with my oil. The marked level was about four inches above the full mark. This would explain the rough running but now I need know the options of how the diesel is getting in the oil.

Thanks, RBC

 

[rsewill]

That much in a seemingly good running engine is probably a bad injector. You will notice it really isn't a good running engine if you push it hard.

 

[Hooked_on_HP]

I would guess a seal on the injection pump is leaking. On the type of injectors that you have it would be hard for that much fuel to leak by. Any idea how long it took to get that over full.
Bill

 

[RBC]

I would be guessing but I am pretty sure I have checked my oil in the last 5 or 6 hours. I am not sure how the injector pump is driven and if there is a gasket on the block side of the pump that maybe leaking. I am not sure what the can looking part is on the front of the pump. Thank you

 

[Harry in Ky]

The can looking thing is the fuel shutoff solenoid (which you must remove before you remove the pump). If you have fuel dilution in the quantity you described, your pump needs work. It's not something you do at home, and be prepared - most pumps of this type I've sent off came back with a bill for $700 to $900.