Ford 6640 Injection Pump Leak

[Royz28]

I have a 1994 Ford 6640 tractor that has developed a fuel leak from the injector pump on the top half. It is leaking from behind a snap ring holding small tab held in by a snap ring. I found a parts diagram on the CNH Parts website that shows two orings are behind it. Before doing this and out of caution, I wanted to ask this question here as to what should I do? My plan is to remove the tab and try to replace the orings without removing the pump.

Any advice is appreciated.

Wasn't able to upload photos in this post but was able to in the post below.

This post was edited by Royz28 on 12/31/2021 at 04:12 pm.

 

[Royz28]

The tab I am referring to is number 44 in the parts diagram.

This post was edited by Royz28 on 12/31/2021 at 04:13 pm.

 

[Dieseltech]

That's the CAV/LUCAS/DELPHI model DPS pump. The leaking O ring can be replaced after removing the snap ring and pulling the steel cap, O ring is on the cap outer edge. DO
NOT go any further, the second O ring is inside and is not your leak anyhow. Be aware, when one leak starts, others usually show up soon after and pump may need pulled
from engine for repair anyway. Hydraulic head O ring, advance O rings, throttle O rings, and drive shaft seals are other common leaks over time.

 

[Royz28]

Thank you. That is what I had hoped. In the parts diagram there is a spring in that same detail. Anything gonna come flying out when the cap is removed?

 

[Dieseltech]

Nope, nothing will fly out. Just pull the snap ring, steel plug. Replace the O ring, lube well and replace plug and snap ring.

 

[Royz28]

Thank you.

 

[Destroked 450]

Replaced that seal on my 6610 this past summer
Remove the snap ring then pull the plug out with a pair of pliers or small vice grips
Make sure to lube the seal before reinstalling the plug
I shaved the side off of the seal the first time and it leaked
Dish washing detergent is a good seal lube

 

[Dieseltech]

For diesel repair I prefer slick lube like STP or motor honey..

 

[sotxbill]

Yes,, the spring/thingys behind it can and does fly out!!!! Ask me how I know.

 

[sotxbill]

And the parts will bounce off of you and go the other direction, hopelessly lost.

 

[Dieseltech]

Then something was wrong with your pump. When done carefully nothing else will come out.