gearbox output shaft nut size?

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mrb27
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Post Thu Aug 16, 2012 7:51 pm

heya, going to change the output shaft seal on the gearbox tomorrow and was wondering what size the nut is? im thinking a 28 or 29mm deep socket, both of which i dont have at the mo :P
just cant seem to find the size.. all i got is m20x1,5 and the part number 23 21 7 509 948. the gearbox is a manual 2.5i with the slim alloy gear link thing not the steel wide one going from the box past the gear lever hole if that helps lol

a little heads up would be great so i know what im off to machine mart for in the morning :)
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DanThe
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Post Thu Aug 16, 2012 8:22 pm

30mm, you need a special socket as they are not usually deep enough to clear the spigot that engages in the front of the prop.
Grrrmachine
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Post Thu Aug 16, 2012 8:44 pm

Just a quick q. Any reason you're changing the output seal?

I only ask because while leaky 'boxes are common, failed output seals aren't. It's usually the selector rod seal just above it.
mrb27
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Post Thu Aug 16, 2012 8:46 pm

hmm ok thanks :) i do have a 30mm deep socket buts its an impact and is far too thick.. im not shavin one of them down :P
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leeparkes
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Post Thu Aug 16, 2012 8:46 pm

Needs to be slim too so the socket sits inside the output flange, i got mine from Halfrauds and worked perfectly.
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
DanThe
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Post Thu Aug 16, 2012 9:40 pm

I have a deep halfrauds one too, had to have the inside machined out though
mrb27
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Post Fri Aug 17, 2012 12:07 am

Grrrmachine wrote:Just a quick q. Any reason you're changing the output seal?

I only ask because while leaky 'boxes are common, failed output seals aren't. It's usually the selector rod seal just above it.
oh, so normally the oil is running down past the output seal and fooling the untrained eye :P

well ill still swap it out just in case but looks like i should look into a new selector rod seal too then :O

thanks for the heads up :)
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leeparkes
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Post Fri Aug 17, 2012 12:14 am

DanThe wrote:I have a deep halfrauds one too, had to have the inside machined out though
Think mines one of the Advance ones with the 6 sides.

Btw to the OP dont forget to pop the locking washer out before trying to get a socket on, it gets tapped into the flange to keep the bolt where it should be.
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
Grrrmachine
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Post Fri Aug 17, 2012 7:39 am

mrb27 wrote:
oh, so normally the oil is running down past the output seal and fooling the untrained eye :P
Exactly. Output shaft requres dismantling of the output (as you can see). Selector shaft seal just pops out with a small-blade screwdriver winkeye