Have been having fun and games with the gearbox for the last 2 weeks, a gearbox change has been on the cards for a while as the synchromesh on 3rd and 4th has been pretty non existent for the last couple of years, I've just been double declutching and it's not been too much of a problem. The plan was to get another box as a temporary replacement and refurb the original box at my leisure over the winter before switching the boxes again, I bought a 4 pot gearbox locally and managed to get hold of a 6 pot bellhousing for £25 so I got the two bellhousings swopped over and pulling the old box out.
After following the green bible's instructions of just undoing the rear propshaft from the transfer box and finding that there's not enough room to clear the bellhousing studs before you hit the prop I eventually removed the prop completely and the box flew out with no problems.
At least the box going in is a bit cleaner!
With the replacement box in place I did an oil change on it now that I could get an oil pan under it, the oil change came with a prize:
Bugger.
I filled the box up anyway and as the floor was still out and the propshafts still removed I fired up the engine to run it through the gears, all of the forward gears sounded fine but reverse was very different, quite clunky, not a good noise. I thought as it was a temporary replacement I could live with that so I got everything reassembled and took it out for a mile long test drive, when driving there was a clunking from every gear and a vibration from the gear lever. 'Bother' thinks I. At this point the plan changed, the new plan was to do a very quick refurb on my original gearbox, sort the synchro and as many bearings that I could get to with out splitting the gearbox from the transfer box and then get it back in the vehicle asap. I spent some time scraping all kinds of filth off of my original box and cleaning with gunk before opening the box, at this point it was fairly evident why the synchromesh didn't work, the last two oil changes I've found a synchrohub spring in the catch pan and had hoped that there'd be one remaining, apparently not, all were AWOL.
EDIT - photobucket apparently doesn't like this video, it just shows the baulk rings completely loose.
Started pulling things out:
The baulk ring looks ok but the dog teeth are knackered - junk.
This snap ring became the bane of my life for a while, 90 minutes later I was the victor.
Third gear used to whine, apart from the pitting there's no obvious wear but this is being replaced anyway.
The dog teeth on second were knackered too so that's going in the bin along with it's baulk ring that had similar wear.
My reverse selector fork had some 'interesting' wear on it, where the rest of it went (and when!) I have no idea, probably ground into a million tiny swarf particles over the years. New vs old, spot the difference.
This is everything that got replaced, primary pinion bearing, layshaft front and rear bearings, mainshaft front bearing, 2nd and 3rd gears from the main shaft, 3rd/4th synchro hub, reverse selector.
Then it was back to stripping the vehicle out again and swopping the box for the second time in 10 days, this time round it only took me 9 1/2 hours from picking up tools and getting things out of the vehicle to starting it up and taking it out for a test drive, for an 'enthusiastic amateur' working on my driveway I'm happy with that.
I drove the refurbed box a few miles and it's behaving itself, its really weird having synchromesh again, I'm finding myself still double declutching which I guess isn't a bad thing.
The ball bearing that came out of the replacement box was one of the detent balls, which one I don't know and quite why it's making noise I'm not certain of, it's possible the gears aren't meshed properly after having the layshaft disturbed when I took the bellhousing off, I'm not sure, I'll open it up at some point and have a look.
