I've got a relatively new leak from the Full-Load Adjusting Screw, located near the top of the pump at the rear (output) end of the pump.

Since I haven't yet figured out how to post images in the body of the text here, the screw I am talking about is designated as #10 in this diagram:

http://www.christianristow.com/images/pumpdiagram.jpg

This screw has a locknut, and I tried simply tightening this locknut, but to no avail; it still leaks.

So I tried backing it out, and got it out until it exposed an unthreaded part with a small O-ring. I suspect this O-ring is my leak problem. However, at a certain point the screw didn't want to come out anymore, and I was a bit scared to just pull it out. Obviously, I can't replace the O-ring without removing the screw.

Has anyone had experience with this screw, or a leak coming form there? Does anyone know if replacing this O-ring will fix this leak?

The truck is getting harder to start, and my theory is that the diesel is leaking out of the pump when it sits.

Any help would be appreciated!!

Happy New Year to all!

CR

 

Once you unscrew the screw just pull on it and it should come right out and yes replacing the oring will stop the leak. I just changed mine.