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Gearbox

Lining up the gears

0.15mm play Finally we had all the spare parts to re-assemble the gearbox. Especially the rings to reduce the 2nd and 3rd gear float took some time arrive. There is one ring that locks up the 2nd and 3rd gear that is available in oversized thicknesses. However that availability appeared to be only hypothetical. We realized the end float for the 2nd and 3rd gear would end up just a bit over the upper spec limit. Well, it is what is it is. Several experts assured me that even twice that amount would not be an issue running the car.

gearbox is ready While we were putting the gearbox together, Daan took some pictures. We also engaged the different gears to check and double check the function of the gear selector. For the fun of it we added a picture to show the gearbox with the selector rods extracted and 2 small inserts showing the geabox with the 2nd gear engaged and the reverse gear engaged respectively... We want to share our learning. The only thing that did not work was the turret with the stick itself. There is a pin with a spring in the turret. Its function is to create extra pressure moving the stick to the left to differentiate between the reverse gear and the 1st/2nd gear. If you push the stick gently to the left and then forward, you will be in the 1st. Pushing it harder against some resistance, you will be in reverse. The pin and the spring responsible for this extra resistance turned out to be jammed. To disassemble everything I drilled out a locking pin. After cleaning out everything I used a new type of aluminium solder material. That is, new to me. Worked great!. Just have to heat it up considerably and evenly. Good to know that aluminium is that easy to repair.

Ho Ho Ho The gearbox itself it completed, including a new clutch pressure bearing and refurbished clutch slave cylinder. It is clean enough to put it under the Christmas tree. With the gearbox under the tree and still a few days for Christmas, it is time for some reflections. What else are we going to put under the tree? Dear MG enthusiasts: it is time to clean off the dirt from your hands too and do some serious shopping for your friends and family... and your MG :) ...

On gears and bearings...

Speling in de laygear The only part that has not been taken apart up to now was the gearbox. To still work on the gearbox once the car is rebuilt is not quite possible. In fact to later work on the gearbox would require the engine to be take out to access it. All the more reason to make sure the gearbox is in perfect condition before we build it back in. We were not able to do a test run with it, so all we can do is visual inspections and check for tolerances. The literature also gives some indications of part that have the tendency to wear. The layshaft is one of them and indeed that was indeed a part in need for replacement.

Worn gearbox parts We will have to replace that along with the layshaft bearings. Of all the 3 synchro rings, the one of the 2nd gear was definitely the worst. The 4th gear ring is still good enough. The 1st gear is not synchronized, just like the Peugeot 404.

The cardbox gearbox For the rest the the gears themselves look ok. The play on the layshaft is on the high side. We will first put the new layshaft in with new rings and then we can check again... For the time being we put all the gears and parts in a cardboard box: the 'gearbox'.

'How on earth will you be able to put it back together again', is what some of you will think. Well it is not that bad. There are a lot of drawings and sketches in books, so for now I think we will be ok. Time will tell: If the MGA once completed all of a sudden has 4 reverse gears and one forward, we definitely did something wrong...