D311 Stuck Fuel Pumps

The pump plungers are a very close tolerance fit in the pump bores so any varnish or particle that gets in between will stick them tight enough that the springs cannot push them back down. Spray them and attempt to pry them back down and then back up to work the penetrating spray into the bore.

If that doesn't work you can get new aftermarket pumps.

Looking good! I'll see you tomorrow in Temple at the show.
I'm finishing up the first load.
Roby Whitehead

If it comes to removal, the lifter yoke will screw out of the lifter and let the pump come out of the housing. Just have to set them back to 1.736" at TDC before reinstalling the pump.

Maybe they aren't stuck that tight and some prying and spray will get them loose. I don't think there is any way to drive the plungers out of the pumps from the top, so you are limited to tapping GENTLY on the exposed part of the plunger and gear quadrant. I would be cautious about twisting the quadrant as that is clamped on in a calibrated position and if it moves on the plunger, the fuel delivery rate will be affected.

I learned how to take these types of pumps apart and getting them un stuck at Santa Margarita right out there In the dirt on a D-8. Several guys helping out and giving advice. Me looking on and learning. That 8 and the operator was one of the best pushers out there. They are rather crude as diesel pumps go. Just go easy.

Remove fuel lines at pumps. Spry penatrating oil down into top of each pump and let soak overnite. like one other gentleman said, don't force rack back and forth too hard or you will slip the gear on the plunger. You're a long way from buying new pumps. Bill Walter, Fuel pump and injector service. [email protected], 1 816 805 1834

I made some progress. The first pump the plunger came out and I was able to remove. The second pump I held the lifter up by lifting and placing a socket next to it and under the washer then I could unhook it from the yoke. I feel confident that 3 and 4 will come out, I'm concerned though that when I first started work on it I thought the shaft was frozen and it actually was the plungers stuck, when I pried the shaft forward I'm wondering if I rotated the gears on the plungers? There is a small dimple on the plunger and it is lined up with the seam where the gear is split. One is lined up directly and the other is a little off. Was that how they marked them after they were set? If they are off I could always send them out to get calibrated.