Firstfives.org

Hi all,

I have a 1976 520 with a 78-80-ish 528i motor and running gear in it. The car has been off the road since 1994 and I'm the fourth or fifth owner since then. The motor is rebuilt, and looks wonderful, but I've struggled a lot with sorting out little issues to get it running properly. In the end I got a guy who has a lot of experience with M30s to work on it. He had it running, but when trying to set the timing with the distributor, the car would spit the distributor out of the block and stop, at which point he sent the car back to me and told me to fix it, then he would do the timing. I found out that one of the springs way down in the guts of the distributor had become dislodged and would jam it occasionally. I put the spring back, despite knowing it might have sustained some damage, because I could not find replacement parts. However, after putting it back together, the car now only runs on 3 cylinders. All plug wires were checked with the timing light and three of them are not getting spark.

My plan is to buy a replacement distributor, but the numbers stamped on the housing have me confused. Do they make a difference? My current one is a 0237302013, which seems very uncommon. Can I buy any Bosch PGFUD6, or are there internal differences?

Any other tips on parts to replace or ways to troubleshoot this?

Cheers,
Kjetil

The distributor is driven at the camshaft end, both meshing with helical gears and the distributor is bolted to the head. Is the entire distributor being “spit” out of the head? I’m not sure how that could happen but then I’ve never experienced what you’re describing. If that did happen you have a much bigger problem than a spring within the distributor. Use realoem.com for part number comparisons and you may want to research your engine number to determine the year it was built.

The distributor to head bolt must have been missing. That's the only way it would get "spit out".

The distributor to head bolt was loose, in order to adjust the timing. When the spring caught in the distributor mechanism, it stopped that from rotating and subsequently the helical gears forced it out of the block.

But my question is whether there are any internal differences in the various Bosch PGFUD6 distributors, like different springs or weights or similar, that would affect how the motor would run?

The motor number seems to be 7989156.