Hi everyone,
I believe I‘m having an issue with my fuel lift pump. I‘ve heard that these can wear out and not supply the engine with enough fuel (well, supply the injection pump, anyway). Is there any way I can get the parts to rebuild this pump (the one bolted to the side of the injection pump)? It seems like the parts are pretty hard to find.

And yes, I did check all filters, screens, etc, there is no blockage there, and no leaky lines.

The car will run and start, and drive around the neighborhood, but it will starve for fuel under load, and die when I declutch. The revs will go down, no matter how far the accelerator pedal is depressed, sometimes it‘ll pick back up, other times not. I will have to start the engine on the side of the road with the pedal fully depressed and the starter engaged for a while (I do know to only run it for up to 20-30 seconds) and it will start and run very weakly, then it will pick back up over the next few seconds until it is running right again. Then I‘ll put it in gear and go, and it will starve again. Sorry for the wacky description, but I‘m trying to remember as I type.

Any help would be greatly appreciated.

Thank you guys in advance!!

There is rebuild kits for the fuel supply lift pumps.

There is an item called the fuel pressure relief/overflow valve that appears to be a banjo bolt but has a valve inside of it. That s what controls the fuel supply pressure. So that can have issues.

And obviously there is filter, fuel tank screen and tank vent issues that can affect what you are speaking of. There can also be air leaks in a worn-out hand primer or suction side of the fuel system.

There is a small number plate on the fuel supply/lift pumps that tells you what model it is. With that a Bosch Fuel Injection Shop can see if it is still available.

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84 300D, 82 Volvo 244Gl Diesel

The old Mercedes lift pump rebuild it was just a valve kit and some copper crush washers. To do a full rebuild you need a tiny O-ring. I only used to have the size of that for my 1984 300D.

I am not saying that this is the correct part number- Diesel Feed Pump For Bosch Fp / Ke 22AD112/2 - 0440003176 - Pump / Feed Pump But that gives you an idea of what you are looking for on the lift pump number plate.

They are also selling complete likely Chinese made fuel supply lift pumps on eBay but you need to properly identify which one you have. You cannot go by exterior looks.


If you have a FP/K22 model fuel supply lift pump it may look like this https://injectionpumps.co.uk/product/lift-pump-repair-kit-for-bosch-fp-k22-pumps/
Note there used to be a lot of different kits. Some come with the stuff for the glass bowel and filter some don't.

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84 300D, 82 Volvo 244Gl Diesel

Thank you, Diesel 911, I have the FP/K22 M7 pump. All of the kits I see don‘t have the replacement check valves in them. I heard this is a wear item, and it causes a decrease in fuel pressure. It is a flat-ish round disk that goes at the bottom of the chamber where the fuel lines go into and out of. It looks like some of these kits have valves that look almost T shaped.

Sounds like it has disc valves. The 240D fuel supply pumps with 2 bolts use disc valves. The problem there is I don't know what size they use.

But I am wondering if that is what it is supposed to have.

Also post in this part of the forum: Vintage Mercedes Forum - PeachParts Mercedes-Benz Forum

When I look it up I keep getting the same kit with the 2 plastic T valves.

I believe there is pictures in this thread of the disc valves. Note I have no idea what the 2 items with the really long springs are.

Most importantly it shows the small O-ring.

Also, when I worked in a fuel injection shop, I would occasionally run across a pump with the piston spring broken. 2 in the 5 years I worked there.

Refreshing the fuel pump on an OM617 (European spec – non turbo)

May getting closer: W115 220D and 240D Lift Pump Valve/Rebuild Kit

The part number is for a valve only kit but at the end is info on the O-ring

This has that the Mercedes valve kit is discontinued.

https://www.youtube.com/watch?v=DibpC-4DsfU

This eBay seller has a whole fuel injection pump rebuild kit that appears to have the 2 needed disc valves the copper crush washers and the little O-ring.

Below is the ebay ad title. I don't know if that matches with your fuel injection pump or not.

If you look at the sellers ad and view all of the pictures there is an exploded view of the fuel injection pump and the kit parts. The kit is mad by SPACO which when I worked was an Italian company. We used quite a few of their kits in rebuilds and they work fine. Have no idea where they are made now. Note there is a number plate on the main body of the fuel injection pump.

eBa ad title:
Mercedes Benz 1417010001 DGK127, DGK207 Fuel Pump Gasket Kit PES-4M 200D 220D

The kit is $40 with free shipping. And if the other stuff fits your fuel injection pump you may need that someday.

I will post again if I happen to find more info.

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84 300D, 82 Volvo 244Gl Diesel

Thank you, very much!! That is extremely helpful, and looks like what I need!!