Draining the Gearbox oil

[Stephen Archer]

I need to replace the oil in the transmission of my Series 1. Is it necessary to remove both drain plugs (the one underneath and the one on the side) as the one on the side appears almost impossible to get at ?
Thanks
Steve

[Huib]

Yes. You have to remove both.
To get to the rear one you have to cut a piece of an Allen key off and operate it with a spanner

[Stephen Archer]

Thanks Huib, that's my challenge for this weekend.
Regards
Steve

[Stephen Archer]

One other thought,
Are the plug threads tapered or do I need to use washers under the plug ? If so, what diameter are they ?
Thanks
Steve

[william]

You will need a fiber washer with the size of 28mm out and 22mm in.

[Tim Heath]

I use soft aluminium washers (found a bag in the spares I bouht with my last car) - of course you could use copper which is what I always found on undoing these horrible plugs. You may be unlucky and find it so tight the brass has worm and youcannot get it undone.

Tim

[Stephen Archer]

Thanks guys,

Used the cut-off piece of Allen key to remove the plug and aluminium washer to seal.
Not as difficult as I feared.
Regards
Steve