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Back axle - mixing and matching

Evening all,

Thanks to those (and there were many!) who answered my ad for halfshafts and CWP, and apologies to the gentleman whose number I lost and haven't got back to - you'll know who you are!

I've now sourced second hand, but need advice on how best to fit a roller bearing pinion into a ball bearing axle casing (both "D" type).

I already have new bearings (including the ball bearing at the pinion end). My simple mind says "turn off the step at the pinion end to make it just like the one I'm replacing". However, I gather that some would call that a retrograde step.

The alternative is to shell out fifty odd quid on a roller bearing (which I suppose I don't mind, if it's the proper thing...), and then drill/make up a location peg, and somehow adjust the spacing between the roller bearing and the matched pair of ac bearings adjacent to take account of the difference in the width of the races. That may be the proper engineering solution...but it's also where I get a bit lost!

Will it be obvious where the peg needs to be? Any advice on spacing the bearings? Or is plan A acceptable after all?

Oh, and I may still need a decent pinion flange if anyone has got one.

Thanks for your thoughts, as ever.

Geoffrey

Location: Norfolk

Re: Back axle - mixing and matching

I think you need to be a bit more specific about which Pinion you have. The part number is stamped on it.
You also need to be aware that the 1938/39 pinion 1A7297 with ROLLER bearing behind the gear has different (metric size) angular contact thrust pair 3MDJT25 = ID 25mm X OD 62mm X wide 25.4mm which has a single inner race and 2 separate outers ---difficult and expensive if you can find one (£45 each).....it has a rear roller 1 1/8" X 2 13/16" X 13/16"

The previous pinion 1A 7239, had double purpose bearing 1 inch X 2.5" X 5/8 with ROLLER 1 1/8" X 2 1/4" X 5/8"

Mar 1935 pinion BP117 had double purpose 1" x 2 1/4" X 5/8" with BALL journal (pinion shaft rear end) 1" X 2.5" X 3/4"

Have a look at the A7 Friends Archive for the spares lists which show different years details.

My late 1938/39 with the roller has a lip at the rear of the torque tube that stops the outer bearing race sliding into the axle casing and there is a peg ended bolt that screws into the torque tube at the front of the bearing to stop it sliding forwards....but there are different methods for different bearings/years/pinion shafts; and the various spacers and bearing houses are different.

Dennis

Location: NW Devon

Re: Back axle - mixing and matching

Thanks Dennis, I haven't got hold of it yet! But I can say it is the 5.25 ratio and therefore (I think?) pre- '37.

I'll check the part number when I get it and research as you suggest.

G

Location: Norfolk

Re: Back axle - mixing and matching

There's some info that may be useful in this thread:
http://pub25.bravenet.com/forum/static/show.php?usernum=2099944454&frmid=5&msgid=1016918&cmd=show

Location: N W Kent