15 replies to this topic

[BaronVonchesto]

Hi all, finishing the rebuild of my rod change A+ gearbox here, and it's time to torque up the two big nuts. Am following Guesswork's guide, so it says to disengage the gear selector by turning the lever 180 deg anticlockwise.

 

my problem is i can't seem to do that! it goes up to about 90 deg where it gets stuck. the selector is blocked by the fork for what i think is the 1st and 2nd gear. Am i supposed to force it or something? Saw a video on classic mini DIY of Cole doing it and he disengaged the selector effortlessly.

 

As far as I can tell the interlock spool only goes in one way so i don't think i fitted it the wrong way, but it feels like the bottom lip of the spool is catching the fork or something...

 

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[Its a min]

I had a similar problem but with a little bit of jiggling as I was turning it with very little force and it turned.

[Pigeonto]

Done one today. No force, ever.

Lots of wriggling on the selector shaft and at same time encouraging the 1st/2nd and 3rd/4th hubs to their neutral positions then start again.

Assuming the assembly is all correct up to this point

Edited by Pigeonto, 03 June 2019 - 08:30 AM.

[unburntfuelinthemorning]

As above, don't force it and you're right it is the first/second gear fork.  The third/fourth fork is at the input end of the 'box.  When fourth is selected it connects the input shaft directly to the mainshaft, the layshaft still turns but doesn't transmit any drive.

[BaronVonchesto]

think i'll just get a friend to help and we will tighten both bolts simultaneously. that way we wont have to lock up the gearbox since i still cant disengage it...

[Spider]

The Bell Cranks are like just out of alignement.

 

Check Reverse is completely disengaged and then jiggle the 2 Syncho Hubs back and forth a bit, with some light-ish turning pressure on the Selector Shaft, the Cranks will align.

[mini13]

now that is an interesting thought.

 

obviously you would only need to lock it into 4th, and you wouldnt have any torque going through the laygear so no risk of damaging teeth. you could just put a breaker bar on the diff end, lie the case on its side, and torque the input gear in a down ward motion against the floor, could make the whole process a lot easier as a one person task.

 

Anyone got any good reasons why this shouldnt be done? apart from needing two specialist sockets.

 

 

 

think i'll just get a friend to help and we will tighten both bolts simultaneously. that way we wont have to lock up the gearbox since i still cant disengage it...

[Spider]

 

Anyone got any good reasons why this shouldnt be done? apart from needing two specialist sockets.

 

 

 

think i'll just get a friend to help and we will tighten both bolts simultaneously. that way we wont have to lock up the gearbox since i still cant disengage it...

 

 

The issue I see is that you don't know and have no way of measuring how even the torque between the two nuts is being distributed. It sorta sounds fine on paper, but the later Mainshafts have a different thread to the 1st Motion Shaft for one thing.

[Rorf]

Is the selector fork new? Maybe the casting is a bit out at the bottom and so the selector is making contact with it when you are trying to turn the selector anticlockwise.

If that is the case then you will have to dismantle the box again and file that area of the selector to ensure the selector head can move past it.

[mini13]

I was wondering about that, as the shaft is floating I was thinking the same should be applied at both ends as if they were torqued individually, obviosly were it a stud with 2 nuts through a material this wouldnt be the case though...

 

I cant find any references/info on line, and I dont know enough about threads to work it out.

[Spider]

I was wondering about that, as the shaft is floating I was thinking the same should be applied at both ends as if they were torqued individually, obviosly were it a stud with 2 nuts through a material this wouldnt be the case though...

 

I cant find any references/info on line, and I dont know enough about threads to work it out.

 

In all likelihood, it would probably end up close enough, but I'd prefer to do each nut on their own, then you know they are both 'there'.

[BaronVonchesto]

the selector forks are not new. I thought of changing them, but when i read here that even new forks can come out of clearance i figured there wasnt any point in changing them.

 

ill try jiggling the synchros like moke suggested, but otherwise what ill do is put a breaker bar on the small nut side and get a friend to step on it while i torque the big nut, then swap and do the same to the small nut.

 

that way its unlikely the toque will be off. will use red threadlocker as well to be sure.

[Spider]

Aside from doing the Nuts Up, you would want to be sure you can select all gears before going to far.

[BaronVonchesto]

i ended up doing the 2 socket thing. was really difficult to torque it up because even with someone standing on the gearbox, it still was lifting off. here's hoping the torque is close enough and the combo of threadlocker red and the locktabs will be sufficient.

[unburntfuelinthemorning]

You need someone very heavy standing on the gearbox.  Failing that pushing down from the ceiling whilst standing on the 'box helps.

 

Another way is to put the 'box on the engine and lean the engine on it's side while someone stands on it.

 

All good fun.

Edited by unburntfuelinthemorning, 14 June 2019 - 11:56 AM.