Distributor - Purpose of Felt Pad

[Traveller]

For over 35 years of wrenching, I've always wondered what that circular felt pad is for that sits in the distributor shaft above the advance hold-down screw and covered by the ignition rotor.

Any ideas?

[964TargaC2]

Back in my British car days (MGA /TR3)you were supposed to put a drop or two of light machine oil on that pad..

[Traveller]

Originally Posted by 964TargaC2

Back in my British car days (MGA /TR3)you were supposed to put a drop or two of light machine oil on that pad..

That is what I remember reading a long time ago.

If that is the case, what purpose does oiling it serve; there are no moving parts? I remember asking myself that back in the days of VW Beetle ownership.

I'm just finishing off my dual-distributor rebuild and as I was about to put the ignition rotors on, I remembered to install those felt pads I had placed in a small zip-lock bag.

[Flieger]

Maybe just a hold-over from non-fixed advance (pre-Motronic) distributors?

[Traveller]

Originally Posted by Flieger

Maybe just a hold-over from non-fixed advance (pre-Motronic) distributors?

A Rennlister stated that the "oiled" felt pad was to inhibit corrosion.

I wonder how effective it was with an ignition rotor covering it. Maybe to inhibit corrosion of that screw under the rotor.