Marelli Ignition Distributor Rebuild and Run Test

Hello! Today we take a look at an ignition distributor. This one came to us very hard to turn. After disassembly and cleaning, we solved the turning problem but found some other wear. We address the wear points and rebuilt the ignition distributor.
Next, we ran it up on our distributor machine. This shows the advance in half crankshaft. Right at the top of the advance curve, you can see a bit of points bounce, where there are more firing events. We correct for this, and with out the correction, you could see bounce at a much lower point.
Enjoy the build and run test.
Thanks for watching!

[@donthompson9525]

Kurt rebuilt my Marelli several years ago. I enjoyed seeing the process.

[@klassikats]

Glad you could see how it is done. Kurt

[@charleseckberg1947]

National treasure to the Porsche community here.

[@klassikats]

Thanks. Kurt

[@JF-4444]

Cool test machine!

[@klassikats]

Thanks! Kurt

[@Dernie1000]

Great Job!

[@klassikats]

Thanks! Kurt

[@RichieRich845]

Looking forwards to to this rebuild 👍

[@klassikats]

Thanks 👍 Kurt

[@JF-4444]

So many good tips in the video.

[@klassikats]

Glad you like them! S

[@joshuahonel7321]

Great video!

[@klassikats]

Glad you enjoyed it Kurt

[@RichieRich845]

👍

[@klassikats]

Thanks. Kurt

[@kevinthomas8768]

Kurt , is that a roll pin holding the gear on or a pin that has been peened. I peened my new pin but I’m not happy with the results. It’s to thin on the edges and I worry it will flake off. Does a roll pin work and will it stay put ? Thanks.

[@klassikats]

On the Marelli distributors, I use a coiled pin. Mainly because the pin size is 5 mm versus the available 4 mm pins used by the Bosch distributors. I have been using a coiled pin in distributors for the last 25 years. Never had a failure or an issue. Kurt

[@kevinthomas8768]

Kurt , when installing the new shaft pin to hold the gear on , should I slowly peen it or is a harder hitting process ? Getting the edges peened over is tougher than expected.

[@klassikats]

Kevin, Peening the pin takes quite a bit of force. You also have to make sure that the distributor shaft is well supported so that you do not damage either the distributor housing or bend the shaft. Kurt

[@kevinthomas8768]

@@klassikats Thanks Kurt.

[@kevinthomas8768]

@@klassikatsKurt I peened the pin into shaft while supported but I’m not happy with the results. The pin was an OEM part but the process of peening made the edges of the pin very thin and I am worried about it flaking off in the engine. Any suggestions?

[@dickieb2233]

That's really informative thanks. However, you mentioned case hardening after excess heat of welding. Please, how is that done? CH not the welding.

[@klassikats]

To case harden a part it will need to be sent to a specialist shop. Kurt

[@dickieb2233]

@@klassikats ah thank you. So it is not like annealing or quenching in oil and water.

[@klassikats]

It is similar to that process but just in a more controlled environment to maintain hardness levels and depth. Kurt

[@dickieb2233]

@@klassikats Thank you. Brilliant work and it has made me less inclined to want to strip these engines myself. Better leave that to you. 👍