How to make your own 27mm allen / hex tool to remove the selector cover and timing hole plug in the trans

DIY 27mm Tool

Here are a few pics to show how to get the 27mm selector cover removed without a 27mm tool...

An old rusty 19mm bolt, the lockrings from a Pelolok bolt kit, half a dozen washers for the 13mm bolts used around the 020 case, a MK2 rear shock spring cap perch washer, an old square nut, and a couple random washers.... something in there should do the trick.

This works fairly well, the bolt turns a bit then gets wedged in place. As long as the head of the bolt stays pushed in flat against the selector cap, this would work...

Using the square nut, it fits much better than a couple stacked washers, and shims the bolt better. 3 nuts slightly thinner would be ideal, but this works as well. I could find 3 nuts and hit them on the grinder wheel to fit them perfectly if desired....

I found the nut for the 19mm bolt, and it is taller, so it fits better into the hex head.... weld the nut in place, shim it with 3 smaller nuts as shown above, tack those nuts in place and you have a tool for the selector cap, and the green timing check plug!

The above method works great in a pinch, but if you'd like a more permanent solution that's better fitting and easier to find when you need it, read on:

Head to the hardware store with your 27mm wrench or socket and find a 27mm bolt and nut.(2 nuts, depending on which one of the options below you choose.)

Either butt 2 nuts against each other on the bolt, weld an old socket to the bolt, or weld the nut to the bolt, then use a 27mm wrench or socket to remove or install the plugs in the trans.

I found this in my tool box, it's part of an old bicycle crank arm puller. Turns out, it fits in the trans plugs.

I made my own 27mm hex tool, simply by inserting the crank puller into the socket and welding them together:


Below you can see the crank arm tool inserted in the timing hole plug and the selector cover. It's almost a perfect fit. Welding a 27mm bolt into a socket would work just as well, if not better.

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