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View Full Version : 2 x gearboxes with mainshaft pegs sheared off - repair?



65s2a
11th November 2014, 03:19 PM
My S2A started gear crunching noises when moving from 1st to 2nd for a few days. Then last week, something went and I could only select 3rd gear and had to drive home across the city in peak traffic with only 3rd gear (H&L). Gearbox out on the weekend, brass distance piece 2nd/3rd was broken. This is easy to replace however, both the pegs in the mainshaft are broken. The one that fixes the brass distance piece and the smaller one that fixes the thrust washer.
So I opened up a spare S3 gearbox that I had to see what it was like inside thinking that I might change it over and it too has the two pegs on the mainshaft sheared off.
I tried to drill the larger peg but it is hardened steel. Does anyone have any ideas or advice on how/who/where to get the pegs removed or the holes re-machined? Anyone else had to do this?
Otherwise the gearboxes are generally both OK.
Any ideas greatly appreciated. Thanks Les

chazza
12th November 2014, 08:34 AM
...Gearbox out on the weekend, brass distance piece 2nd/3rd was broken. This is easy to replace however, both the pegs in the mainshaft are broken. The one that fixes the brass distance piece and the smaller one that fixes the thrust washer.
So I opened up a spare S3 gearbox that I had to see what it was like inside thinking that I might change it over and it too has the two pegs on the mainshaft sheared off.
I tried to drill the larger peg but it is hardened steel. Does anyone have any ideas or advice on how/who/where to get the pegs removed or the holes re-machined? Anyone else had to do this?

Any ideas greatly appreciated. Thanks Les

This is a very common fault with the Rover box and according to Wagoo happens because the main-shaft flexes - his advice is to not use high revs in 2nd and 3rd.

But to answer your question; I had success on my S1 box by tapping the shaft on my anvil, which allowed one of the dowels to drop out of its hole slightly and so be drawn out with Vice-grips.

The second dowel was encouraged to move with a hook and pick set and it lifted with a powerful magnet; I used some CRC to encourage it to slip.

I think I was very lucky but it occurs to me now, that if they won't move at all, it may be possible to get them out using spark-erosion - a friend of mine had a broken tap removed from a cylinder head using this method.

Good luck,

Cheers Charlie

65s2a
14th November 2014, 07:32 PM
Charlie, thanks for the reply. I never heard of spark erosion method. I will research it. I'm also surprised with such a common problem not to have a ready solution available. If I figure out how to fix the mainshaft pegs on the two gearboxes I have (otherwise they are great) I will post it here. Cheers Les