Beck TD, Part 53: A Special Transmission Tool

I've been enjoying this project to rebuild an antique Volvo M41 transmission - it has been quite the learning experience. The M41 is an overdrive transmission, and that is a very different beast from the M40 trans that I recently rebuilt. One of the interesting aspects is that the overdrive shift action is done with hydraulics at very high pressure (over 500 PSI), using an oil pump built into the overdrive unit.

Of course, when you're rebuilding, you want to inspect and repair that high-pressure pump, and it turns out it has a part that requires a special tool to remove. It's called the "non-return body" and it's down in the bottom of a hole. This photo is a bit hard to read, but you can see the non-return body at the bottom of the hole, and the part itself is shown in the inset at the top right. It's not a normal hex head. Instead, it is sort of an oval with flat sides:

More on the "Very Specific Jack"

In my last post (link) I detailed the creation of a "very specific jack" to use with my new ER32 Spin Indexer (link). Its mission in life is to support the far end of stock mounted in the indexer, far above the milling machine's table. Here's a photo:

A Very Specific Jack

I recently posted about an addition to the machine shop equipment at the Grant Street Garage: an ER32 Spin Indexer (link). In response to that post, my friend Jake pointed out that I should have something at the far end of the work in the indexer to keep it from flexing, lest I get inaccurate or inconsistent results. Even a large rod can flex a few thousandths of an inch with just fingertip pressure. This photo makes the issue clear:

Beck TD, Part 52: Saving a Switch

Here's the second post in a row about extraordinary efforts to try to save a part that is basically junk! The photo below shows two switches removed from the broken shifter in the M41 transmission I'm trying to resurrect (see Part 51 for more details):

The ER32 Spin Indexer

Wow, if you even made it past the title of this geeky machinist post, you must be pretty interested in machine work! A spin indexer is a useful tool that lets you precisely locate round stock in a milling machine, and rotate it very accurately in one degree increments.  This photo shows the indexing wheel that has holes every 10 degrees, and the 10 offset holes that bring it down to one-degree increments. There's a pin, not shown, that locks the rotation at the desired setting.

Waste Not, Want Not

In Part 51 of the Beck TD saga, I told about the start of a big experiment: rebuilding a locked-up, rusty M41 overdrive transmission. That is progressing pretty well, but I took an interesting side trip the past couple of days. In the last post, I didn't mention that in addition to the rust and bad bearings, the M41 transmission had taken a hard hit at some point - so hard that the "remote shifter" had broken in two! In the photo below, the top part shows the remote shifter currently in Beck TD, and the lower part the pieces of the broken shifter tail from the M41. The hit was so hard that the heavy shaft inside was bent as well, and the top of the shifter plate was bowed.

A Mildly Embarrassing Repair

It was back in 2016 when I received a used Sherline lathe for Christmas. Click here for the post announcing that addition to the shop. Here's a photo from that post: