Interesting Pertronix Problem - PeachParts Mercedes-Benz Forum

Litton · #1 12-10-2003, 12:11 PM

I am still fighting a small problem with my Pertronix installation. No matter what I do, the vacuum retard/advance no longer functions.

The vacuum is fine, the module is fine, the plate moves great.....everything is mechanically OK and the centrifical advance works just fine. Only there is no change in timming even though the plate is moving. Prior (2 hours) to the Pertonix installation the vac retard worked perfictly.

I have had several conversations with Pertronix and they are very interested.....but baffled. We are at the point where they have asked me to send the complete distributer to them for evaluation. This I am going to do in a couple of weeks, but, in the meantime I will just run without the timing advance when the A/C on.

psfred · #2 12-10-2003, 12:32 PM

Does the Pertronix module move with the plate? If so, I don't see how it could not be working. If not, you won't get any change in timing.

Litton · #3 12-10-2003, 02:46 PM

That is exactly why Pertronix is concerned. Everything appears to be fuctioning perfectly but the timing doesn't change.

That said, I was able to observe the plate and module moving by removing the cap/rotor/dust cover and applying vacuum to the module with my hand pump. The plate would move at ~ 6" of vac. Then I would reassemble everything (hand pump still connected but no vac), start the car, set timing to +7 and then pump the vac to ~15". No change in timing.

I can only think of two things, the angular displacement is not sufficient due to an error in the sensor, or the assembly is binding when I reassemble. In fact I think I will go check if there is any possiblity that the dust cover is contacting the module.