How to repair cracked transmission shift boss

[kevinm]

I noticed that one of the shift bosses on my 1990 syncro transmission is cracked and has almost fallen off. Any suggestions on how to repair this?

Fom below, passenger side, looking slightly toward the front:

From below, passenger side, looking more toward driver side:

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90 Syncro Westy, "Ludwig"

[dhaavers]

Gotta say it: DO NOT try to weld a spare piece of magnesium on there. Just…don’t.



- Dave

Sorry…someone who can actually help will be along in a minute.
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86 White Wolfsburg Westy Weekender
"The WonderVan"
<EDITED TO PROTECT INNOCENT PIXELS>

[uberaudi]

Here's a quick plate I made to address my severely corroded mounts on an old trans.

Brickwerks also has a kit you can just buy now too.
https://brickwerks.co.uk/product/gear-linkage-repair-plate-kit-t3-83-case-saver/
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'84 Adventurewagen 1Z TDI, '08 Audi Avant Quattro 6spd BHW TDI

[kevinm]

Thank you Uberaudi. I have dangerously little expertise in fabbing something like what you did so I ordered the Brickwerks product. I'll report back once installed.

- Kevin
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90 Syncro Westy, "Ludwig"

[dobryan]

That Brickwerks kit is a great price too!
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Dave O
'87 Westy w/ 2010 Subaru EJ25 (Vanaru) and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[kevinm]

Following up on this. I indeed ordered the Brickwerks repair kit ( https://brickwerks.co.uk/product/gear-linkage-repair-plate-kit-t3-83-case-saver/ ), and prior to installing it I attempted to JB Weld the two shift boss pieces back together.

I started by mixing up some JB Weld and clamping the two pieces together. As it turns out, a large clamp works well for this, as the jaw opposite the shift boss is stopped by the other side of the gear carrier. I rested the clamp on wooden blocks whose height exactly matched the needed height of the clamp. After clamping, I also inserted into the shift boss hole a dowel wrapped in parchment so that the hole wouldn't get clogged with JB Weld.

I figured I'd use a lot of JB Weld because why not? I attempted to keep the existing mating surfaces clean. In the photo below, the two bolt heads on the right side are removed from the transmission gear carrier and then re-attached over the Brickwerks repair plate.

Here you see these two bolts removed and the repair plate ready for attachment. I used the washers as shown to ensure the plate mounts evenly.

After attaching the repair plate, the existing shift rod bushing plate can be reattached to the shift boss. It's slightly forward of its prior location by the thickness of the repair plate, but I didn't notice any difference in shifting ease (or lack thereof).

Since I had JB Weld around the shift boss, I did not tighten the bolts attaching the shift rod bushing plate to the boss much past about 12 ft lb, and I used nylon insert locknuts (pictured) on them to prevent them from loosening. So far so good.

I'm really satisfied with this Brickwerks part, as it fit perfectly and saved me several hours of fabrication trial and error. I don't believe they import to the US right now due to tariff issues, which is really unfortunate.
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90 Syncro Westy, "Ludwig"