Engine Series a mag pinion

[Stanley Chappell]

two questions which is the best mag pinion tufnol or white nylon type who sells them note series a 500 with 3 holes
also the self extracting pinion has a very small gap to the crankcase any ideals on the best way to seal I am using
belt drive to dynamo and don’t want oil creep in the mag cover
thanks
Stanley Chappell

 

[A_HRD]

The Series A mag pinions are much bigger toothed than the postwar ones. On that basis I am quite happy to use the Acetal/Delrin white ones made by Maughans.

Peter B

 

[Vincent Brake]

POM, delrin or acetal, expands a geat deal. Causing load on bearings, if not taken into acount
Tufnol is much lower in expansion

 

[A_HRD]

Most 'A' single mag pinions seem to have a very sloppy fit. However, a shim or two under the mag provides even more clearance.
I'm not sure Tufnol ones are available anymore(?), but I'd like to be proved wrong...
Peter B

 

[Vincent Brake]

Yes available

HPC gears.

Bit machining yourselves