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Sideroad
13th February 2011, 01:50 PM
The other day just days from getting the 2A re-rego-ed I broke another gear stick. I got stuck in 3rd, but used low range 3rd, high range 2wd 3rd and over drive. Hence it was a 3speed 3rd gear box. :)

First time it happened was about 6mths ago and left me in neutral only just out of an intersection and blocking one lane. Followed by a hasty tunnel cover removal and selecting 2nd to get me home.
It was replaced with a dodgy welded one I had in a pile of spares. This lasted a surprising 6mths, given 4 mths of that was spent in the shed while the suspension and drive-train were repaired and numerous roadworthy items attended to. Looking at the welds, I am surprised it last more then one gear shift.
I considered welding the original one, but noticed that the ball is of a different steel and had originally had the stick fitted into the ball.
I considered that the strength would never be the same if I welded it, as the weld location is at the end of such a big lever (gear stick) and would fatigue over time. Given that the original lasted over 40yrs, I thought to do the same.
I bored out the stub in the ball to a depth of 17mm (in a lathe, but could be done in a drill press or by hand) and chiseled out the thin wall left after the boring. I could have bored deeper but figured it was deep enough (I didn't want to risk machining the original bore)
I then linnished and hand filed the gear stick end down to 0.2-0.3mm larger then the bore size. I left the gear stick in the freezer for an hour and heated the ball over a gas cooker (not too hot, but enough to expand the metal).
I had made a jig to support the threaded end of the stick on hard wood, whilst the end was help in the vice. Using vice grips, I placed the ball on the end and bashed it down using a copper mallet and lump hammer, finishing at the depth mark already on the stick end.
Now I just have to re-assemble it all.

drifter
13th February 2011, 03:23 PM
Well done!

JDNSW
13th February 2011, 03:57 PM
Well done. I would have been inclined to have turned a cone to shrink onto the lever and come up against the flat on the ball. This would spread the load. I'm afraid I have never done this - always just welded the lever back on!

John

Sideroad
13th February 2011, 07:07 PM
Thats a very good idea. Only issue would be that the bend is only about an inch from the end now. But if I had cut the bend off, rebend further up the shaft, slid a snug fitting cone on then do my tolerance fit, slide the cone back to the ball and then tig weld the cone onto the flat of the ball.
Maybe next time, but great suggestion.
If it lasts another 40yrs then I'll have plenty of time to redo it in my 70s :)


Well done. I would have been inclined to have turned a cone to shrink onto the lever and come up against the flat on the ball. This would spread the load. I'm afraid I have never done this - always just welded the lever back on!

John

Lotz-A-Landies
15th February 2011, 12:53 PM
A similar repair was done in 1952 by the Army Design Establishment when tropical testing the Holden grey engine in a 1948 Land Rover.

The main difference with their repair (done by the side of the road in Western Qld) was that they tapped the ball and threaded the stick before welding to stop the stick turning.

Well done by the way. :)