Primary chain case replacement options?

My belief is that the 16H primary is unique to the rigid frame singles only and that is based on the '47 parts book and the 3 different inners that I have in my basement, none of which will fit my plunger Inter.

Previously Michael Rettie wrote:

My belief is that the 16H primary is unique to the rigid frame singles only and that is based on the '47 parts book and the 3 different inners that I have in my basement, none of which will fit my plunger Inter.

Wish you (Or anyone for that matter) had responded to my thread a couple of weeks ago, regards a 59 alternator Model 50 engine and a 57 pre F/bed frame, Michael. An alternator Dommie inner is not lining up but what I can tell you, keeping on topic; is that there is only one sealing band listed, meaning the circumfrences are all the same. Could it be that just the inners have different fixings and the basic Dynamo and alternator outers are the same?

It's more complicated than that, Neil. The shape of the top edge changed quite a bit too, initially when the face-cam mags were first used (they had a taller points cover which requires a jiggle to remove). Later cases still were relieved completely along the rear top edge. This may have had something to do with battery tray fitment.

I've also come across aspects of the footrest spacer opening not lining up but haven't been able to pin down why and when. Possibly with the gearbox changes they had more or less room available and had to re-position ? I can imagine that the laydown box limited the possible location of the footrest through-stud on the timing side and of course this had a knock-on effect on the primary side.

One thing that is really clear with Norton's policy of gradual evoloution rather than radical change is that many parts are clearly recognisable as Norton, will often look pretty similar and yet won't fit when you get them home. How types of rear brake pedal were there during the 1950s ? About a dozen, I think.

Previously richard_payne wrote:

It's more complicated than that, Neil. The shape of the top edge changed quite a bit too, initially when the face-cam mags were first used (they had a taller points cover which requires a jiggle to remove). Later cases still were relieved completely along the rear top edge. This may have had something to do with battery tray fitment.

I've also come across aspects of the footrest spacer opening not lining up but haven't been able to pin down why and when. Possibly with the gearbox changes they had more or less room available and had to re-position ? I can imagine that the laydown box limited the possible location of the footrest through-stud on the timing side and of course this had a knock-on effect on the primary side.

One thing that is really clear with Norton's policy of gradual evoloution rather than radical change is that many parts are clearly recognisable as Norton, will often look pretty similar and yet won't fit when you get them home. How types of rear brake pedal were there during the 1950s ? About a dozen, I think.

Interesting stuff for me; I have a hybrid; 48 plunger inter with 37 MS inter engine neatly connected with what looks like a WD (it's green inside....) primary cover system. How can I tell which one it is?

Are there any identifyiing features to look out for to discern which type I have? I guess being green it will be16H...

The comment on the sealing band being all being size I believe to be incorrect. I bought one for my 35 CS1 which was like a sloopy boot. I eventually bought a NOS one that fits, but with modern superglue solutions, rubber is about one of the best materials to cut and shut.

I appreciate your knowlege folks.

Cheers

Jon

Thanks Richard and Jonathan (Sorry to piggy back on this thread but I got nowhere with my own version)

So it appears there were a few versions, especially with regard to inners. I'm stumped at the moment. I am using the standard AMC box with the 57 frame. I had thought of taking my Ex WD 16H primary apart to see if that inner would fix it with new holes for the alternator housing but ideally:

Are there any suggestions for getting the Dommie inner case to line up. It can only be the frame that is the issue as the engine is a 59 alternator single and g/box is AMC..

Any ideas having come this far?

Thanks for your understanding, Stuart. Good luck.