Fuel distributor rebuild question.

[3DawgDoug]

Bringing my 1988 300SE back to life. I'm rebuilding the fuel distributor at this point.



I've removed the adjuster screw covers, but have not touched the adjusters screws themselves. I have no way to measure their position so I hesitate to move them at all. Everything else has been removed from the two halves of the distributor, and they are soaking in Simple Green to clean everything up.


Can this job be completed without removing the adjusters? In my searches of the web, I have not found the procedures for setting these. Anyone have a link to the method?



Thanks for any comments.

[Frank Reiner]

3D:

In each of the lower chambers is a spring. Each spring is unique, and the adjustment screws below the springs are for the purpose of matching each of the individual flow controls to the others. The springs are to be kept with their original chambers (and adjustment screws). The adjustment screws are not for field service use.

[3DawgDoug]

When I tore the unit down, I kept each chambers set of parts separated to keep each set of components to the place they came out of. You just confirmed what I thought about the screws..


Now on to cleaning all of the little bits.


Thanks for your reply.

Originally Posted by Frank Reiner

3D:

In each of the lower chambers is a spring. Each spring is unique, and the adjustment screws below the springs are for the purpose of matching each of the individual flow controls to the others. The springs are to be kept with their original chambers (and adjustment screws). The adjustment screws are not for field service use.

[optimusprime]

Outer screws are set for each cylinder and must not be removed .Did you measure plunger height before removing it to re seal the O rings

[3DawgDoug]

The adjusting screws have not been touched. The cover screws and seals have been removed. There is no adjustment to them that I can find.

I did note the alignment of the slot in the plunger adjustment/retainer screw (hope I used the correct term) before removing the plunger. It should come back to the setting as found.

[lsmalley]

Originally Posted by 3DawgDoug

The adjusting screws have not been touched. The cover screws and seals have been removed. There is no adjustment to them that I can find.

I did note the alignment of the slot in the plunger adjustment/retainer screw (hope I used the correct term) before removing the plunger. It should come back to the setting as found.

https://k-jet.biz/wp-content/uploads/2019/06/Rebuilding-a-Cast-Iron-K-Jet-Fuel-Distributor-V2.pdf See if this helps.

[lsmalley]

Post a picture

[3DawgDoug]

I got it all buttoned up last night. Went very easy. Now to get it mounted back on the engine and see how it runs, I hope.

Not sure what I would take a picture of.

[3DawgDoug]

I installed the rebuilt FD. The job went very smoothly. Installed it this afternoon.

Jump out the FP relay to test everything out. I hooked up all of the fuel supply and return lines and left the individual injector lines loose. When I power up the FP, I can hear the Start Injector spraying fuel. Depress the Throttle Plate and nothing to the other injectors.

Fuel Pressure Regulator?

[3DawgDoug]

I installed the rebuilt FD. The job went very smoothly. Installed it this afternoon.

Jump out the FP relay to test everything out. I hooked up all of the fuel supply and return lines and left the individual injector lines loose. When I power up the FP, I can hear the Start Injector spraying fuel. Depress the Throttle Plate and nothing to the other injectors.

Fuel Pressure Regulator?

[nulu]

Is the fuel pressure from pump to fuel distributor good? you have an accumulator at the rear of the car if the diaphragm is leaking internally ie bypassing pressure you need to check that too, FUEL INJECTOR opening pressure is approx 4.3 to 4.6 or 3.7 with used injectors , get a fuel gauge to perform tests , you can also do a fuel supply test should pump out 1 liter of fuel in 20 seconds

[3DawgDoug]

I learned a valuable lesson this weekend. Make sure you have enough fuel before you start testing. ;<(

Anyway, I got my pressure gauges Saturday. Bad weather held me off today. I got to inspecting the FD .a little closer. It is missing 3 of the 6 micro bucket screens that are set under the feed pipe fitting in FD. I have found a web page listing some 5.5x8.4mm micro bucket filters. They list these as suited for use in the K-Jetronic FD, but there is nothing mentioned about the KE-Jetronic.

Can anyone confirm that filter size for the KE?

[3DawgDoug]

Had to take time off for surgery. Everything went well so I'm back to it.

Got the FD on and tested it. The engine ran at 6.1 to 6.2 bar, but really rough. Had to adjust the HEA and got 5.1 and 5.4 bar. The book calls for 0.4 bar.

Is 5.1 bar enough pressure to run this engine? How do I raise the pressure?

[3DawgDoug]

Still no joy. I have replaced just about everything I can think of.
New fuel pump,
New fuel filter,
New accumulator,
New pressure regulator.

When I fired everything up, still no start. I have 0.4 bar of differential pressure and was holding 4.9 to 5.3 bar of pressure. Shut the FP off and checked the accumulator for leaks. Found some fuel and I was able to tighten one more flat of the nut and the leak was fixed.

When I started the FP again the pressure would only reach 4 bar and no differential pressure.

Is my new FP defective?

[lsmalley]

Why don't you try testing the pressure right at the main fuel line before the distributor and find out. I just fixed resolved the same issue not too long ago. I think it was a combination of injectors and fuel pumps.