Author Topic: Primary Case Oil Seal  (Read 271 times)

Online Miker

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Primary Case Oil Seal
« on: 20.06. 2020 05:58 »
I need to change the Primary Case Oil Seal on my 1951 za10 motor (where the gearbox shaft goes through ). What is the best way to remove the rivets? Also what to use to reinstall ( Rivets , screws , etc)
Cheers,
            Mike

Online Greybeard

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Re: Primary Case Oil Seal
« Reply #1 on: 20.06. 2020 08:58 »
Be very careful with this area; the metal is thin and the rivet holes are close to the edge.

I drilled out the rivets and reassembled with small nuts and bolts*. Normal Pop rivets are hollow so will leak oil. Maybe you could obtain blind Pop rivets.

*I found that the nuts rubbed against the gearbox sprocket. I turned them round. The bolt heads still rubbed. I had to grind the heads thinner.

Offline AdrianJ

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Re: Primary Case Oil Seal
« Reply #2 on: 20.06. 2020 17:15 »
I think I drilled it out and used 6 BA nuts and bolts and Loctite.
It’s OK so far but I’m not confident.
Adrian
'53 Plunger Flash, Steib S500.


Online morris

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'58 BSA A 10 SA
'52 BSA A 10 Plunger
'55 MORRIS ISIS
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Re: Primary Case Oil Seal
« Reply #4 on: 21.06. 2020 01:04 »
Thanks everyone , Very much appreciated *smile*

Online Minto

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Re: Primary Case Oil Seal
« Reply #5 on: 22.06. 2020 01:30 »
I ground the flat heads off the rivets with a Dremel then just pushed the remains through with a pin punch.
I replaced them with three flat head M4 screws with nuts, but had to file the heads down about a mil, i shaped some washers for the nut side to lock into the raised edge of the lip on the inside plate then loctiited the nuts, then bent an edge of the washer over the nuts. The abutment ring keeps the clutch thrust washer well clear of the nuts. Nowt rubs but it's all a bit fiddly.
Enjoy
Jase
52 A10 plunger
Aprilia RSVR

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Re: Primary Case Oil Seal
« Reply #6 on: 22.06. 2020 10:02 »
To protect the seal I put a plastic bag over the gearbox shaft before inserting it, then pulled the bag off.