Gear box locked up

[ETTony]

I am now reassembling after renewing the clutch, timing stuff, etc

About to mate the engine and gearbox housing and find the gear box is stuck in gear
It does rotate, the back and front rotate on oposite directions. (Is it stuck in reverse ?)
Tried disengaging, no go.
Rotated from the output and pinon nothing freed off.

At some point i stood the gear box and bell housing on its nose. Maybe this dislodged a ball bearing ? The gear stick has been wiggled around as I moved it.

What to do ?
Take it to the garage who is servicing my cylinder head. Get proper mechanics to free it.
"Pop" the top off the box, going well out of my comfort zone here.
Or kick it around my garage floor hoping it fixes itself.

I think i have answered my own question, unless the etype collective has a simple solution.

Thanks team

[ETTony]

4th option was to phone a friend (who was not available earlier)

Removed the cover, when I moved the reverse fork the gears freed up, phew.
Need a gasket, then job done.

[angelw]

Tony Wrote:

Removed the cover, when I moved the reverse fork the gears freed up, phew.
Need a gasket, then job done.

Hello Tony,
You have fixed the issue but perhaps not the cause. There are two ball bearings and a roller separating them, at the front of the Top Cover (inside); their function is to stop being able to select Reverse and Forward gears, or being able to move 1st/2nd and 3rd/Top selector rods at the same time. I would be investigating why you were able to have a Forward Gear and the Reverse Idler in mesh with Reverse Gear simultaneously.

Regards,

Bill

[christopher storey]

I would be investigating why you were able to have a Forward Gear and the Reverse Idler in mesh with Reverse Gear simultaneously.

Regards,

Bill

I'm not sure that he did . he said as I understood it that the gearbox was stuck in reverse as denoted by the input and outputs rotating in contrary motion. If he had two gears selected simultaneously, the gearbox would have locked up completely

[angelw]

Christopher Wrote:

I'm not sure that he did . he said as I understood it that the gearbox was stuck in reverse as denoted by the input and outputs rotating in contrary motion. If he had two gears selected simultaneously, the gearbox would have locked up completely

Hello Christopher,
You're correct. That will teach me to read all the Posts in the Thread. I read the Thread Title and the resolve and assumed that the gearbox was in Reverse and a Forward Gear.

Regards,

Bill

[ETTony]

Thanks for your input guys.
All good now.
Next job, remove, clean up and paint my hood frame.
I already have the correct paint.

[Hugo]

I was going to ask whether you had taken the lid off & simply not got the gear lever in the slots of the selector rods - knocking it into reverse and holding it there. If you hand't taken the lid off prior to this happening, please ignore this post!

[scratch01]

ive got exactly this same problem , i will take top cover off tomorrow , my only concern is why ?? and the gearbox has just been re built -- could do without this as i need to fit the engine

[angelw]

scratch01 Wrote:

ive got exactly this same problem , i will take top cover off tomorrow , my only concern is why ?? and the gearbox has just been re built -- could do without this as i need to fit the engine

Hello scratch01,
When removing and replacing the top cover, the gear selector forks should be in the neutral position and similarly the synchro hubs.

If the gearbox is either locked solid, or locked in one gear, particularly if the gearbox has recently been rebuilt, it could be that the selector rod lockout ball bearings and spacer roller may be out of position, or omitted. You will find these located in the guide bore for the centre (1st/2nd gear) selector rod at the opposite end of the top cover to the gear lever. During assembly, its not all that difficult to have the ball bearings fall to the bottom of the outside selector rod guide bores (3rd/4th gear and reverse). This condition can lead to more than one gear selected and a locked gearbox. Ball bearings at the bottom of the guide bores will inhibit the movement of the selector rods.

Regards,

Bill

[ETTony]

I have deduced that mine locked because I had up-ended it, which allowed the reverse lever in the box, to drop backwards or forwards.(gravity)
The gear selector had not been moved. So the gear selector fork, was out of sequence with the reverse gear lever on the gears.

[angelw]

Tony Wrote:

I have deduced that mine locked because I had up-ended it, which allowed the reverse lever in the box, to drop backwards or forwards.(gravity)
The gear selector had not been moved. So the gear selector fork, was out of sequence with the reverse gear lever on the gears.

Hello Tony,
The top of the Reverse Lever would have to move forward to have the Reverse Idler Gear engage with Reverse Gear. This can't happen inadvertently without some other problem existing with the Gear Selector Rods. A pin at the top of the Reverse Lever engages with a Reverse Selector Fork on the Reverse Selector Rod (Right most looking from the top). Accordingly, the Reverse Lever can't move unless the Reverse Selector Rod moves. Movement of the Reverse Selector Rod is inhibited by the Lock-out ball bearings and spacing roller at the front of the Top Cover, designed to prevent more than one gear being engaged.

Therefore, the Reverse Lever could only move independently if the Top Cover and Selector Rods weren't correctly assembled, the Lock-out ball bearings were out of position, or missing, there was a problem with the Reverse Selector Fork, or the Reverse Lever drive pin was missing or not engaged with the Reverse Selector Fork.

At some point i stood the gear box and bell housing on its nose.

If it were possible for the Reverse Idler Gear to move due to gravity, the location of the fulcrum bolt in the Reverse Selector Lever, gives the Reverse Idler Gear the mechanical advantage. The size of the Reverse Idler Gear is that of a medium sized apple and the weight of approximately 1/3 of a house brick. Accordingly, with the Gearbox and Bell Housing sitting on its nose, the weight of the Reverse Idler Gear and gravity would ensure that the Reverse Idler Gear wouldn't engage with Reverse Gear.


Regards,

Bill