Quote from: Rupert on 18 February, 2022, 18:08:16
It may be more a question of do the followers and the inserts they run in really need changing? If the followers go up and down ok without excessive side to side play then leave well alone?
There's a lot of side play with the inlet follower particularly but, more importantly, they really need to be in another (half decent) crankcase casting.
Quote from: Rupert on 18 February, 2022, 18:08:16
There's one correct original cam follower on eBay at the moment from dynamo dunn, so you can at least see what it looks like. Item 325015367365
I'm slowly getting to grips with this now; I've been scouring the parts book looking for something that looks like what is already there but, of course, it's another red herring! I have already seen that follower when searching EBay but it looked completely wrong (i.e. completely different to what is in there already) - now I know why!
That would also explain why the tappets were so difficult to set as they are partially located "up the tower" and not nicely in the chamber intended for them. So I'm guessing that another PO modification was custom length push rods to accommodate the over-length and bushed cam followers.
Do you know what the significance of the partly helical holes are? Is it to reduce surface area and thus friction, maybe to impart rotation of the follower to spread the wear? Any ideas?
Anyway, thanks for you help, now at least I understand what should be there so I now have a couple of options 1) try and restore it back to the original (parts permitting) or 2) contrive a similar replacement system to that that is present using more freely available M20 parts (for example).
Cheers!
Alan