Sprint gearbox selector fork screw fallen out

[GrahamFountain]

I lost two gears from the box - 1st and second -, and they didn't fall out underneath. So I removed the extension from the top to see if they'd gone in there, to find that the screw holding the relevant selector fork to the rod has fallen out.



So the first question is how worried should I be about where it's gone and if I should be, what can I do about it.

I have a spare extension, but it is a bit different from the one that's on.





The top one is off the spare box, and the second the original one from the car. Both boxes have the same number V2947 on the casting. There's a longer number underneath that, but it will take some effort to read and copy here.

So the second question is do those differences matter enough to worry about, at least short term?

But then, even if they don't, is it better to swap the whole extension or steal the screw from the spare and put the original back? If the latter, any suggestions for torque? And do I want Locktight in there?

Graham

[Carledo]

You WILL need to find the original screw! It's bound to catch in something and destroy it if it hasn't done so already.

I'd suggest draining the oil (you never know, it might wash out of the drain hole) You might even be lucky enough to have a magnetic drain plug that it's stuck to. Still not found it? Go fishing for it with a "magnet on a stick" or better still, if you can find one, a magnet on a flexible rod. At least it's a steel bolt!

If it's intact when you find it, you can reinstall it (with lots of Loctite) or i'd use the bolt from the spare housing. It may be finicky of me, but I find it pays, in silencing effects, to keep bits of a well used box together as much as possible.

Steve

[GrahamFountain]

Thanks for that, Steve.

The magnet on a stick I have has a torch on the end and is too fat to get in - but thanks to Prime, I should have a thin'an here tonight. Tomorrow I'll pull the drain and see if I can poke about inside.

I think I've found a replacement for the screw from CanleyClassics - a 122653 Taper Wedglok. It looks right, and it spec. for a surprisingly large range of Triumph gearbox extensions.

The spare extension fits, and I get all the gears. Don't know about overdrive limit and reverse light switches, though.

But even though I did about 10 or 12 miles in 3dr and 4th, after it fell out, I worry about it jumping back into the gears. Maybe with the top off the box and a bucket of paraffin, I can wash it out. Might then have to waste some gear oil flushing the paraffin out.

Graham

[GrahamFountain]

Through the miracle of Amazon Prime bringing me the magnet on a stick today, and daylight saving, I had the chance to go fishing for the Wedglok screw. And lo and behold, after only 10 mins of scrabbling about down the sides of the cogs, it came out. Huzzah!



But, looking at it, and assuming the red stuff is something meant to lock the threads, is it not odd that that said red stuff has obviously not been screwed into the threads of the fork? I will look tomorrow to see if it will go in far enough to reach that stuff, in which case it don't seem like it was assembled right. Or, if it don't go in that far, and it is Loctite or similar, then it weren't dabbed on in the right place.

Graham

[GrahamFountain]

I've had a look at fitting this Wedglok back in the 1st/2nd selector fork, and it did go in at least 2 threads into where the Loktite was on the threads with only hand torque from a 1/4" drive screwdriver handle, using a 70-year-old hand at that.

But the one in the 3rd/4th selector in the original doesn't look to be fully screwed into the fork either, though it seems to be more than hand tight in the selector shaft. So that lets the fork move a bit on the rod. And I assume the fork moving on the thread can't be right - if there's meant to be a bit of free movement on the shafts, that should be between the unthreaded section of the Wedglok screw and the hole in the rod. But why then would it be called a Wedglok bolt?

So I looked at the Wedgloks in the spare remote. The two in its forks are in by quite different depths, but in neither case can I feel any play between the fork and the shaft. Certainly, there's no movement between the fork and the Wedglok, i.e. on its threads.

I also looked at the ROM, but all it says is on disassembly is "Remove three Wedgloks - one from each selector shaft." And on reassembly says "Secure the forks and actuator to the shafts using new Wedglok bolts."

That use of "secure" and the name "Wedglok" suggests to me that the forks are meant to be tight on the shafts, like in the spare, not a bit floppy, like in the original extension. I can't see any obvious taper on the unthreaded section of the Wedglok bolt or in the hole in the selector shaft, but I'm assuming the that's where the wedging is supposed to happen.

So, as the spare remote appears to work, at least it lets me select all the gears, I think I should Loktite the Wedgloks and tighten them so that they "secure the forks... to the shafts" in the original extension and re-fit.

But I am still a bit concerned that the 3rd/4th selector fork has been moving on the threads on the bolt when the bolt seems tight in the hole in the shaft. I assume that if I were just to turn it a little, that would take out the slack between the bolt and the fork, even if the Wedglok bolt don't move down the hole in the shaft. Hopefully, then, if I remove and refit it turned slightly, the Loktite will hold it in place for another few years, if perhaps not 50.

Graham

[xvivalve]

It's likely the movement that you've witnessed has over time cause the bolt to undo itself...

[GrahamFountain]

I'm told by Martin that the Wedgloks should be in almost up to the head, which they are in the spare remote. So it looks like the one on the 3rd/4th fork was in a bit better than the one on the 1st/2nd fork, but still not right. Still, it don't look like the 3rd/4th one was about to unscrew, and on Martin's suggestion that it might have damaged the threads in the fork, I've had a good look at them, and they look fine. Also, I've screwed its Wedglok back in for a test, and it does go in a bit further and will tighten the fork to the shaft, with no slack in the threads. So I think I got away with that one.

So I'm going to follow Steve's suggestion and put the original remote back, after I Loktite the Wedgloks in the forks - keeping them paired as they were (Wedglok in wedlock yet - it wasn't a shotgun marriage if her dad used a Glock).

Let's see if this solves the issue of it being a bit hard to get to second from third, but never from first, and never gruntingly.

Graham