I have a P5 3 litre MK IA 1962 with manual gearbox.
It has locked up in third gear while the swan-neck gearlever shows it is in 4th gear.
Probably the arm operating the rods acting on the gear cogs (the arm that has pear-shape on the bottom end) has jumped out of position.
Does anyone have clever tips on how to rectify this issue ?
Suggestions shall be most appreciated.
Kindest regards,
Christopher
I have finally arrived at a conclusion - happy to report the car and gear box is running flawlessly. On the swan-neck design of the MK I and IA, there is a rod with a pear-shaped oblong at the base. This rod is mounted vertically.
The oblong can break off the rod, so that it becomes 5 - 10 mm shorter. The rod occasionally turns brittle, causing this to happen.
What happens next is that instead of the rod WITH oblong is firmly within the claw of the (horizontal) rod (that is shifting the gears inside the gearbox), the rod being too short will slip out of the claw. It won't be able to move back within the claw for it is just too long (1 mm or so) to get back into position.
Compare it to a joint (shoulder for instance) coming out of position, and a physician forcing it back into position.
What I did to cure the problem was this:
1. Build out the swan neck and rod assembly, by loosening four screws on top of the gearbox, below the parcel shelf.
2. Ascertain if the oblong is missing.
3. Peek into the top of the gearbox, with a torch using your mobile phone camera to watch in 45 degree angle, or use the mobile phone to take a video or photo.
4. You will be able to see the oblong inside one of the claws, unless it has fallen out onto the wayside during driving (this part of the gearbox is open, so it can fall out on the side).
5. Some cars have had the issue before, and instead of an oblong a plastic piece resembling the oblong has been fitted. This piece is called a "Vulkollan". It slides onto the shaft in lieu of the oblong
6. Obtain a replacement rod (for a P4 or a P5; gearbox shifting mechanism is practically the same) with the oblong in place - beware of brittle items that won't stand the test of time.
7. Alternatively, obtain a new Vulkollan from a parts supplier, take the one that is made for the P5 MK II for instance. Fix it to the rod where the oblong is broken off. Note the vulkollan can slide off, so it must be fixed somehow as otherwise you'll be stranded. Drill a very fine hole through the rod and fit a splint, for instance. Glue might work too.
8. Make a TEMPORARY fix; in lieu of the Vulkollan and oblong simply take a wine cork. Drill a hole in it BUT stop the drill bit 5-10 mm from the end of the cork, and mount on the rod. This will make the rod 5-10 mm longer and consequently not come out of position by slipping over the jaws of the horizontal gear switching rods.
8B. reduce the diameter of the cork to 8-10 mm. so it will engage in the jaws and not refuse to enter.
8C. after entering the rod with cork assembly firmly into the jaws, rotate the nut that has three small screws (they have small springs) to adjust he elevation / how deeply the rod with cork protrudes into the claws. This nut and the spring-loaded screws are sitting on the plate the fixes the gearshifter assembly to the gearbox. If the wine cork is "too long" this can be compensated with the adjusting nut by reducing the extent of protrusion / intrusion.