Primary Gear Oiling

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atm92484
850 Super
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Primary Gear Oiling

Post by atm92484 »

I've done several A-Series engines but all have been for Sprites - starting to tear into my first Mini engine so this is probably a stupid question. What keeps oil from leaking past the primary gear bushings and onto the clutch?
GraemeC
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Re: Primary Gear Oiling

Post by GraemeC »

A lot will be flung out of the holes just behind the gear section, which are in board of the seal. The rest is down to the clearance of the bushes on the crank.
atm92484
850 Super
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Re: Primary Gear Oiling

Post by atm92484 »

Thanks. That was going to be my guess. A very BMC way of handling it - don't use a seal, just give the oil somewhere else to go!
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mab01uk
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Re: Primary Gear Oiling

Post by mab01uk »

Early 850 Minis had a thinner tail crank and an oil fed primary gear via an oil feed hole in the crank tail and used white metal bearings, this caused a lot of clutch problems due to oil leaking onto the clutch so the later primary gear had oilite Deva bushes designed by Glacier to run without the oil feed. Dealer fix mods at the time added a brass plug to blank off the oil feed and fitted the primary gear with the new type of bushes, so few remain oil fed unless the owner now desires total originalty!
atm92484
850 Super
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Re: Primary Gear Oiling

Post by atm92484 »

Sounds like I should be happy to have a 998 then!
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