My 11bl occasionally slips out of gear under acceleration, i dont know if it is an adjustment that is needed or perhaps it is wear on a component.
Any guidance would be appreciated
This is most likely to be due to either incorrect setting of the clutch lock or wear in the détente mechanism ….. or a combination of both.
I recommend you start by checking the clutch lock mechanism. This is covered under the gearbox section, operation 117, item 8 in the Slough manual.
The manual assumes you have the bare engine and gearbox on the bench so you will need to undo the front ends of the two long selector rods and then remove the dust cover and gear selector (“Eifel Tower”) to access the adjuster. If possible I would also suggest removing the bonnet for best access.
The locking screw is 10mm a/f. It is recessed so only a box spanner or thin-walled socket will get to it, There is also usually a screwdriver slot in the head – but it is difficult to get it tight enough with just a screwdriver. When loosening the screw, be aware it is very short so take great care not to unscrew it completely because it is a nightmare to get it back into the thread.
Good luck. Let me know if you need more info, I do have a “layman’s guide” on file somewhere.
If that does not cure it the détente mechanism in the gearbox lid is probably too badly worn. Your best bet then is to find a replacement lid in better condition.
Many thanks for the advice Bernie , I’ll investigate the clutch lock over the next few days and let you know how I get on
First I agree with Bernie’s diagnosis. All I would like to add is that there is an easier route to the adjustment, but you do need a flat bladed screwdriver with an 18″ 450mm blade as in the picture. I am also assuming that the original Citroen 10mm bolt with a slot has not been replaced with an ordinary bolt!
1. Remove fan belt.
2. Remove cover from selectors 1 x 17mm bolt
3. Check adjustment. The fork and carrier clamped by the 10mm bolt are serrated and are always relutant to move over each other to get the required 1mm gap when the free play in the pedal is taken up. As Bernie said the bolt needs to be slackened sufficiently to allow the adjustment but care must be taken to not undo the bolt completely.
4. This adjustment should be carried out after the pedal free play has been adjusted as one effects the other.
All this can be done with the bonnet on, and this screw driver will get the bolt tight enough, in 40 years I have never had a problem.
When the corect measurement is obtained ( by sight is good enough, just remind yourself what 1mm looks like) you can check by putting the car in gear (engine not running) letting the clutch out fully and then attempting to move the gear lever.
Good luck, Philippe
Many thanks Philippe I’ll let you know how I get on
Hi folks I’m back again looking for advice, unfortunately the adjustment to the clutch lock has made no difference, I can only assume that the problem is wear on some components in the gearbox, any advice would be appreciated.
It sounds as if the détente notches in the selector rods in the gearbox lid are excessively worn. You will need to re.ove and dismantle the lid to get to the rods.
Usual fix is to replace the complete lid but good condition ones are becoming rare.
Thanks for the advice Bernie, does this mean gearbox removal or can it be done with the gearbox in situ?
The gearbox can stay in place but you will have to remove the rad and the cross member under it.
I suggest you put a packing piece between the gearbox and cradle to support the weight of the box before undoing the 4 fixings between the cross member and gearbox lid. If you don’t fill the gap completely so the box can drop a couple of mm, when you replace the fixings afterwards, there is no danger of trapping the packing piece.
Once you have undone those 4 central fixings, remove the four long bolts attaching the cross member to the jamboneaux. You will then probably have to “persuade” the cross piece a little to actually remove it.
You will then have access to the “Eeifel Tower” which needs to be removed before taking the lid off the box.
… penultimate paragraph should be …
“Once you have undone those 4 central fixings, remove the four long bolts attaching the cross member to the CRADLE. You will then probably have to “persuade” the cross piece a little to actually remove it”.
I have been told that one thing to check is the nut on the lower shaft of the gearbox. If that is loose, it can pop out of gear. I had that problem may years ago; the clutch lock was ok so I checked and tightened the lower nut and that did solve it. It’s worth checking before taking the top of the box off with all that is involved with that.
Thank you all for your advice, Larry can you explain to me what you mean by the nut on the lower shaft , is this behind the outer cover plate?
It is the lower shaft in the gearbox that is accessed by removing the lower plate that is held on by 5 bolts. Behind it is the nut that is held in place with a tab washer. it is possible that the nut has loosened, that happened to me once. Once I tightened it, it did not jump out of gear.