So I have been battling low power issues with my truck since I got it. So I eliminated everything else that could be wrong with it other than the IP. So I pulled the pump and found broken plunger return springs in it. So, being on a low budget, I need to try to fix this myself. I purchased a return spring kit, reseal kit, and a 366 spring.
One question is about the return springs. The kit came with the two springs, the plate that rides on the plunger, and two spring seat washers. The broken setup I have has two shim washers under the spring seat washers. I re-used them after much mental debate. I'm just not sure that is right with the new springs?
The other question I have is about the governor shaft. I didn't note the exact depth before I removed it, but I noticed when I was re-assembling that it might need to be set correctly in relation to the fulcrum lever?
one last question, how difficult should it be to turn the pump? I used a wrench and it was pretty good effort to turn, alot of spring tension, and the shaft moved in and out a little. does this sound normal?

Any feedback would be great. thank you in advance

 

"You have gone where no man has gone before". Well, not really but a lot farther into an IP than me. Keep me posted on your progress and good luck.

 

The pump is suprisingly simple inside, a very elegant design. I'm just not sure about these couple of details. Even though I kind of enjoyed doing this, I don't want to do it again anytime soon, and I sure don't want to break anything. I'm going to hold off on installing it until I get some reassurance that I have everything correct. Gonna kill my dowel pin, drop and clean my fuel tank today. I'm considering taking my pump to the local pump shop to get bench tested before I install.

 

I would get a hold of the shop you got your parts from to see about the shims. On the one hand they could have been for the "old style" springs. On the other, they could be for some other purpose.

I have looked for info on the governor shaft adjustment as well. If I remember right, it is for start quantity adjustment. The two pumps I have had down that far both seemed to be bottomed out, so ????

They do required some effort to turn over, there should be 6 distinct "notches" from the cam plate and the plunger return springs. Some input thrust clearance seems to be normal.

If you don't mind spending the time to R&R the pump, I would just try it. Be sure to have an air shut off, just in case. A crude way to see if it might run is to put the pump and supply lines on, no injector lines. Cycle the throttle and fuel shut off while someone cranks it over. It's kind of messy, but you can tell if it is pushing fuel and if it will shut off. It could save some work or excitement.

 

Thanks Captain. I had the same thought about the springs, maybe an "updated" version. I asked the girl at the pump shop who sold me the parts about shims for under the springs. She just pointed to the seat washers in the kit. I'm not sure she understood what I was talking about.
I also talked to another pump guy, but he only deals with VW, Benz, Porsche, no Dodge. He was helpful, even gave me a set of springs fom a junk VW pump. They were smaller of course, but I noticed on that spring set, 1 shim under a spring and 3 thinner ones under another which leads me to believe there is some sort of static hight adjustment spec on these springs?
I am hoping to find sombody who has done this pump repair?

 

bump, anyone?

 

I bought a core IP off e-bay recently. The auction stated that it had a lot of shaft play. When I got it and pulled it apart I found the springs were broken. I have thought about getting a new spring kit too. I would use the shims that came with the kit.

 

My kit only came with the washers that the springs ride on at the head side, and the diamond shaped spring carrier at the base of the plunger.

Does your core pump have multiple washers under the springs on the head side?
My logic tells me to put all the parts back into the pump that I did not replace.
...but my logic has failed many times.

Learning is fun.

 

Here's what mine looked like when I pulled it apart...



As you can see..or not...that there is no shims. Just the top washer to hold the spring in place.

Is this the kit you got?



I'm really torn on this one. Yes there was probably a reason for the original shims...spring tension and such probably? But do the new springs have the same tension, or lack there of, and therefore need the extra shims?

Think I would try running it with just the new parts. If your truck was running with broken springs, then I think a shim worth a few thousands of an inch might not be noticeable in power and injection pulse strength.

 

That's exactly what mine looked like, one spring in 3 pcs. one in two. That looks like the same kit. Local pump shop had it in stock, told me it was a common failure. I asked what caused it, they told me "age"
I've already built the pump and hung it in the truck, so I'm gonna try it with the extra shims. I'm hoping to try to fire her in the next couple of days.
What's the worst that could happen?
Ill keep you posted.

 

Got her fired up today. Bled , started easily. This thing runs great. My knock in cyl 1 is gone, Power is good, get some black smoke when I put my foot deep, but seems controllable with my foot. Other than the 366 spring the only other adjustment was turning the stock pin deep. I didn't realize how much power these things have. If I did, I would have realized how seriously bad mine was actually running. I guess that was the disadvantage I had by never driving a well running 1st gen before, (or any cummins) now I understand why you guys love these trucks

 

Right on...glad you got it running and the problems seem to be gone.

 

Well... almost all gone. Got an air leak on the lift pump supply I had the tank out, cleaned it out, cleaned the screens, I also replaced the supply fuel line with hose. I also installed a glass filter housing right before the lift pump.
I'm getting a couple of bubbles every few seconds.
So tank is out again. I pressurized the pickup assembly with air and sprayed it down with soapy water, can't find any leaks.

What now? I understand that fittings can suck air under the suction pulses of the lift pump, but not leak under pressure. I just don't want to start throwing parts. Any usual suspects?

 

Yeah I think I have either air in the supply line, or a bad injector (or two). I have a lot of hazing, and grey/white smoke when I idle and for a few seconds when I'm at lower RPM's. Just living with it right now. Will have to do the pressurizing the tank and then look for leaks.

Keep us posted on what you find.

 

so I ran the pickup / return tube assembly in a bucket of fuel. bubbles came from the return straw and were drawn right up by the supply. had bubbles in the clear line before lift pump. so I removed the hose from the pickup and put it in the bucket, away from from the return, bled at filter, bled injectors.
I've got a steady stream of good size bubbles coming from the return line. bubbles before lift pump are gone, engine is knocking.
I've replaced lift pump, fuel heater gasket.

what else could it be?