Case 680E

[Eugen]

@DavidBarkey what confused me is that they show a different transfer pump in the parts manual, which is electric and away from the injection pump. But you're right, there is a lift pump right there on the pump, and it's diaphragm based. I'll try to pull it out today and we see what's what. I think you just figured it out Dave!

[DavidBarkey]

@DavidBarkey what confused me is that they show a different transfer pump in the parts manual, which is electric and away from the injection pump. But you're right, there is a lift pump right there on the pump, and it's diaphragm based. I'll try to pull it out today and we see what's what. I think you just figured it out Dave!

Based on what I could look up there are 2 systems depending on when it was made . Yours based on picture is on the injector pump while the later models are electric in the tank .

Dave

[Eugen]

Pulled the lift pump out but wasn't able to disassemble it completely. This is the type of pump I got:

I'm having a hard time seeing how fuel would not go in the injection pump, as I see no seal separating the lift pump and the injection pump.

Curious what part 17 in the diagram is made of. Steel, or some sort of membrane seal.

[DavidBarkey]

Pulled the lift pump out but wasn't able to disassemble it completely. This is the type of pump I got:



Screen Shot 2022-02-14 at 09.58.36.png



Screen Shot 2022-02-14 at 09.57.43.png



I'm having a hard time seeing how fuel would not go in the injection pump, as I see no seal separating the lift pump and the injection pump.

Curious what part 17 in the diagram is made of. Steel, or some sort of membrane seal.

When you pulled the pump , did the roller have crank case oil on it ??

Dave

[DavidBarkey]

Pulled the lift pump out but wasn't able to disassemble it completely. This is the type of pump I got:



Screen Shot 2022-02-14 at 09.58.36.png



Screen Shot 2022-02-14 at 09.57.43.png



I'm having a hard time seeing how fuel would not go in the injection pump, as I see no seal separating the lift pump and the injection pump.

Curious what part 17 in the diagram is made of. Steel, or some sort of membrane seal.

#17 may have the seal as part of it so as not being serviced separate .
Dave

[Eugen]

When you pulled the pump , did the roller have crank case oil on it ??

Dave

Yes. And there was quite a bit of oil in the opening there, below the cam and shaft, which poured out when I pulled the feed pump off the injection pump.

Had to come to Toronto because of an emergency and got no tools here to take the pump apart.

Took me a long time to figure out what model this pump is. The PO painted over the pump label. Tried to take the thick paint off and the original paint also came off; turns out that I could make out some of the model characters.

It's model FP/KE 22 AD 2??

I see two ways of going forward. Open up this old pump, and figure out why it leaks, then find replacement internal parts.

Or buy a new pump from ebay for about $100 and hope it's a perfect fit, or replace as many of the parts on the old one with transplants from the new one. Found one that is a replacement for Bosch feed pumps models:
FP/KE22AD112/2 FP/KE22AD190/2 FP/KE22AD202/2 FP/KE22AD246/2 FP/KE22AD249/2 FP/KE22AD265/2 FP/KE22AD283/2 FP/KE22AD286/2 FP/KE22AD288/2 FP/KE22AD294/2 FP/KE22AD297/2

[Eugen]

Took the pump apart. Fuel from the main feed pump chamber can only pass to the other side beside the middle rod. There îs no diaphragm or seal membrane of any type, this middle rod pushes the piston on the other side which also doesn't have any seal. It metal on metal, but it seems like a very small clearance between them.


Here's the rod taken out.

Here's the piston.

And what it looks like when they re in.

The bad news for me is that once assembled I tried to blow air from one side to the other and couldn't. So I don't see how so much diesel could migrate over to the injection pump, in such a short time, through such a good seal.


Back to square 1.

[Timj]

Part #518, what is it, did you find it?
Can you follow the path of the fuel through the pump?
It doesn't seem like that rod and piston would seal enough to keep fuel from bypassing it. Is that piston doing the pumping or is it operating something inside that's doing the pumping? (518?)
I can't get my head wrapped around it and how exactly it's working. The steel on steel would seem to be high wear except for running in oil, and it's old and not crazy wore.

[DavidBarkey]

@Eugen Try depressing the the plunger all the way and blow air through . Like an engine it may leak more at TDC than at BDC .
There seam to be a lot of scaring on the piston .

Dave

[Eugen]

Part #518, what is it, did you find it?
Can you follow the path of the fuel through the pump?
It doesn't seem like that rod and piston would seal enough to keep fuel from bypassing it. Is that piston doing the pumping or is it operating something inside that's doing the pumping? (518?)
I can't get my head wrapped around it and how exactly it's working. The steel on steel would seem to be high wear except for running in oil, and it's old and not crazy wore.

Part #518 in the parts diagram I think is just a cap and I don't have it. Here's a sketch of the path the fluid takes when the plunger is pushed in. V1 and V2 are the two valves. V1 opens and V2 closes when the plunger gets pushed in by the cam, and the other way around when the plunger gets pushed out by the spring because the cam turned it's tip away from the plunger.