Gear linkage overhaul

First off: access and overhaul of the gear linkage is extremely difficult. Allow plenty of time for this, and try to obtain all the parts beforehand. The access method is not at all obvious. It got easier the second time, but believe me, you will not appreciate having to detach the linkage more than once…

Removing the linkage

The gearlink is a clever isostatic arrangement. This allows the gear lever to be solidly mounted to the bodyshell, while being isolated from transmission movement. This is really nice, and is a big improvement on horrible, modern, rubber-mounted FWD changes. The downside is that the linkage is pretty complex, and any free play results in a sloppy gearchange. I decided to overhaul the linkage, without realising just how awkward this is:

1. It is best to get the car well off the ground. The rear axle needs to be free, so use ramps at the front and axle stands at the back under the chassis. Chock the front wheels and leave the handbrake off.
2. Detach the exhaust hanger hoops, and the two rear mountings. Let the exhaust hang down, or remove it completely if this bothers you.
3. At the front of the transmission, remove the 17mm cross-member bolts (three each side).
4. Place a jack under the axle tube, and raise it carefully. This will lower the front of the transmission, and allow limited access to the gear linkage. This distorts the propshaft rubber donut, so only go as far as you dare.
5. Inspect the linkage, and try to determine where the free play is. It is wise to have all the replacement parts ready before proceeding any further. As a minimum, you’ll need the four nylon bushes. I needed to replace the lever and link bar as well (although I didn’t realise untill I had removed the linkage from the car!)
6. The long selector shaft is attached to the mechanism with a roll-pin. If you are lucky, this will tap out. It was seized solid on my car…
7. To detach the linkage, first unbolt the left-hand gearbox mountings. There are two bolts through the gearbox flange, and a smaller bolt on the left which holds the static ball joint in place. Remove all three, together with the isostatic link and spacer.
8. You should now have access to the linkage. Note how far the crossmember has been lowered.
9. Locate the 17mm nut which attaches the lever to the gearbox selector shaft. Remove the nut. You might find this easier if you detach one end of the small link rod. This releases rear of the gear linkage.
10. Now move to the front of the linkage and pull off the boot at the base of the gearlever. Remove the bolt to detach the front of the gear linkage. Withdraw the complete assembly rearwards.
11. Yay! The linkage is now off the car and you can inspect it. This is where you find that you have forgotten to order some vital part…
12. You can also remove the gearlever assembly – it is held in place by four bolts. It is a bit of a faff, but it makes it easier to renew the bush and also to clean out any crud that has collected if the boot was split. The interior gearlever gatier was also torn, so I replaced it with one from another (unknown) Alfa. Note that the genuine part is expensive.

Now for the easy hard bit…

The overhaul!

Begin by dismantling the linkage and inspecting all the joints carefully. On my car, the ball joint in the middle of the isostatic lever had suffered severe wear, and was causing most of the slack. Suprisingly, it is available as a separate part (you don’t need to buy the whole lever). However, I decided to renew all the moving parts as there was detectable wear throughout the mechanism. The main inspection/wear points are:

• Front of selector rod: Grooved metal bush, two O-rings, rubber boot.
• Rear of selector rod: Two black nylon bushes, two O-rings.
• Isostatic lever: Main ball joint, two white nylon bushes, metal spacer tube.
• Link bar: Ball joint at each end.
• Static ball joint: Joint, rubber boot.

Most of the linkage is easily dismantled. The fun and games really began when I tried to remove the moving flange at the rear of the selector rod. The flange and bushes are held captive by means of a roll pin in the main shaft. The pin should tap out fairly easily, but needed a lot of force on my car. Then the rear end of the selector rod ought to detach from the shaft. Unfortunately, it was also siezed solid, and there is no easy way to shift it. I used penetrating oil, plenty of heat from a blowtorch, Molegrips on the end of the rod and a decent Stillson wrench on the main shaft. Note that the main part of the rod is hollow, so don’t apply any force here. Eventually it did free, but it was an absolute bugger to shift. Just to really finish things off, I managed to break one of the lugs off the flange while tapping it off. Doh! Better use a soft hammer next time…

The flange is cast iron, so it wasn’t really repairable. Once I had got all the bits, reassembly was fairly straightforward. I used molybdenum disulphide grease (the black, sticky stuff you use in gearboxes) in the joints that need lube, and copper grease for the fixed parts.

The gear linkage is now much improved, and a lot more precise. It’s still not perfect, though. I wonder if it was ever good, even when new..?