Rich9928p

I completed the rebuild of my '79 Euro 928 K-Jetronic fuel distributor. It is not that difficult of a job, perhaps 3 hours if you're methodical and spend a lot of time cleaning things up.

Here are some pictures of the guts, not too much there.

If anyone would like to see how it is done, I prepared a nine page doc with diagnostic information (do you need a rebuild), list of parts (less than $10), pictures and instructions.

I cannot guarantee that it will fix everyone's problems, but it can't hurt to clean out the system and replace 25 year old rubber O-rings. If it does work, it will save you about $500 vs. buying a rebuilt fuel distributor.

Drop a note to info@electronikrepair.com and I'll send you the PDF with all the information. I have a low resolution version that is about 254 kbyte or high resolution version that is 1.8 MByte. Let me know if your email is "industrial strength" and you wish to take the big file.

SharkSkin

Dropped a note... sounds real interesting.

Drewster67

Rich -

Have you reinstalled the distributor yet?. If not, I would like to stop by when you do so.

I'll send you an email.

heinrich

Droppin' da note.

Steve J.

Great timing, Rich. I've got mine on the bench now. I emailed you...

Rich9928p

Steve,

Your OB is a sweet machine, I enjoyed seeing it up on the rack at the 928 OC-IC. We'll have her purring like a kitten.

Styln928

Seems like everyone is jumping on the band wagon. PM on it's way. Great job!

SharkSkin

Nice write-up! Anyone have specs on the "mystery" o-rings?

Rich9928p

Good question.

a) relief valve assembly needs to be 7 mm ID and 2.5 to 3 mm thick.

b) o-ring at the control plunger measured about 27.5 mm ID x 30 mm OD and about 2.5 mm thick

If anyone knows of these type O-rings, let us know.

jpitman2

Control plunger O ring - if ID is 27.5, thick is 2.5, how can OD be only 30? should be 32.5?? or if OD is 30 x 2.5, id=25?
Also, do you know if the Bosch part no for the distributor is the same on all CIS 928s, or did it change? I may be able to pick up a complete 4.5l cheaply, but mine is an S, so......wonder if its the same?
jp 83 Euro S AT 48k

Rich9928p

JP, I may have been off a mm or 2 on the O-ring measurement. I used the "eyeball" test at the hardware store and they didn't have anything near it. Even today mm-based stuff isn't so common in the US.

The Bosch p/n on my '79 Euro fuel distributor is 0 438 100 027. I'm pretty sure they're all the same for 928s.

Looking at the book, the later models were more complex as lambda control was added on Mercedes Benz's later models with KE-Jetronic and Audis with K-Motronic.

jpitman2

We have a sister company that distributes O rings, both Metric and Imp, so I will see if they carry these sizes, and let you know about the hard one.
jp 83 S

Chuck Schreiber

Rich,

Just sent you an email!

Richard S

Rich, i received the file, thanks!!

Peter F

Me to,

great write up, will go and by an o-ring set tomorrow.

Thanks!