gearbox bearing shims

[kevin s]

Thanks Mike,

The only thing that worries me in a gearbox is the magnet coming adrift , I did think about blind drilling the plug from the outside and glueing it in a couple of mm below the surface.

All the parts tp re-build it are here, and I've been going though all the parts to re-use, only issue I have found is the rear bearing carrier, firstly it has this damage that looks like it has been hit with a punch.

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And secondly with the alighnment peg matchong the rear case the cut out for reverse dosen't match.

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Fortunately the one from the second gearbox aside from needing a clean is in good condition and lines up perfectly.

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No idea how this could be wrong unless they changed they position of the peg at some point and the wrong part has been fitted.

[kevin s]

started putting it together today, using the bbq heated up the front bearing and it dropped straight on, washer then tab washer followed by nut done up as tight as I could holding the shaft (need to go and get an old clutch plate from my lock up to finally tighten both nuts).

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For the rear one heated the bearing carrier up and dropped the bearing in with the circlip in place,

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6

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the heated the assembly up put it on the 3rd motion shaft with a spacer shim followed by another spacer shim, the tube, speedo gear, washer, tab washer and nut.
a couple of issues though, while wiping the rear synchro hub over it spring apart, found 1 ball and the 3 springs but 2 balls are still AWOL, used the ones out of the second assembly to put it back together with a tie strap, one tip for anybody else doing this, make sure you get the one flattened off spline in line with the plunger otherwise you won't get second gear (so I ended up doing it twice!).

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that was relatively quick to fix, the second issue came about when I went to fit the reverse gear shaft lock nut, the thread in the case is stripped, looks like it has previously been bodged with chemical metal or something. So I have 2 choices either fit a helicoil or clean up the second case but then it's likely the shim I have bought for the layshaft won't fit, I've ordered a helicoil because I suspect it will be here before I get round to cleaning the case anyway.
So for now all work on it is stopped.

[kevin s]

In the end I bit the bullet and cleaned the second case up reverse idler is in OK, unfortunately it does need a thicker layshaft shim, the one I have gives a snug 0.1mm/ 4 thou clearance, while you could probably get away with it what's a few days to wait until it's spot on clearance next one up is now ordered.

[kevin s]

thought about this yesterday evening and remembered I had the other front thrust washer, so today I measured that, and it is around 2 thou thicker than the one I was using, this means I now have a gap of around 2 thou, I reckon I can carefully take 1 thou off the back shim with a diamond stone to give the required 3thou clearance, after 10 minutes or so I had taken 1/2 a thou off but my fingers were freezing, so another session in the warm in the kitchen this evening should see this sorted.