Author Topic: Another puzzle: plunger A10 drive side crankcase aperture, what size?  (Read 1024 times)

Offline Swarfcut

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Rex, Just nipped into the Engine Shed.  My Early Plunger case has a hole  of 46mm.  The scroll sleeve is a Gnats's Knacker under this and is a tightish minimum clearance fit.  A smooth edged sleeve the same, but the smooth edge is wider than the scroll. Both sleeves are 56mm long.

   Also in the assortment is a later swinging arm sleeve,  51mm long. This is used with a spacer that runs on the later oilseal.  However, this is just a shade under 43mm. diameter. So it looks as if the problem is down to an incorrect size of sleeve. Track down the correct part as I have detailed earlier, and you have sorted it. No need to rip it apart again!

  The early cush drive on the early S/A had a single piece drive sleeve, so I would guess this is also 43mm, and this incorrect part could be what you have and the reason for your leak.


Online Rex

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Thanks again for the info, I shall suck it and see, as they say.