The Mothership Maintenance Log #107

pmac193 said: nice progress!
Thanks :D

I learned some important lessons today. The countershaft came back apart and I found some issues that needs addressing.

The shaft came back apart for two reasons: 1, I had forgotten to install one of the new bearings, and 2, I couldn’t get the synchro sleeve to go into 1st or 2nd gear and needed to investigate.

Disassembled again. I don’t have a hydraulic press, so I just pick up and drop the end of the countershaft on a piece of wood to get the press-fit pieces free :what:

After getting it all apart, I found that by dropping it, I had rammed the reverse gear synchro sleeve into the synchro rings and bent the lower one.

This happened because I’d installed the sleeve incorrectly. It turns out that the hub’s inside teeth aren’t uniform, and some of them have little lips that clip over the snap ring. Note the two deeper wells and longer teeth at the very top of the hub in this picture:

Also in the picture above, see how it’s possible to accidentally fit the sleeve such that those longer teeth fit into the big open rectangle slots instead of the deeper grooves if the sleeve is turned 60 degrees.

Here’s a side view where you can see that two of the reverse gear’s inner teeth are taller and have grooves.

Here’s a picture of the synchro. See how there’s a gap in the teeth every 60 degrees? Well, in one gap there’s a little block that keeps the synchro seated with the hub, at the other gap there’s just empty space for those two deep teeth on the synchro sleep to clip over the synchro snap ring…. So I had installed the sleeve 60 degree off from where it needed to be, and instead of snapping over the ring it just mangled it.

For now I just have one of the old synchro snap rings installed :| oh well.