Monday, May 30, 2016

Operation: Steve Austin

Just like the Six Million Dollar Man, it's time to rebuild the transmission.  I got a start on the third motion shaft (mainshaft) today.  The Haynes manual is pretty detailed about reassembly instructions, so I followed those.

First up - 2nd gear.  I cleaned the gear, loaded the roller bearings up with assembly lube, and installed it on the shaft.

Then, mounting the assembly in a vise with soft jaws (just like the manual says), I began the fight of my life.  At least, that's how it felt.

The next step is to install the thrust washers and the locking collar that holds the gear in place.  There are two little pins with a spring between them that holds the collar.


After fighting with this for an hour, I figured it out.  The trick is to push one pin in (which pushes the other pin out, but more on that later), line up the thrust washers under the pin, line up the collar with the thrust washers, install the collar on the shaft, and push one side of the collar down to cover the pin you pushed in.  Then, you force the other pin in and push down on the collar until it clicks into place.  Once the collar's all the way in place, you rotate it to lock it in place with the pins.

This is impossible.

So I did what any desperate man would do--I cheated.  I modified the collar a bit by giving one of the retaining teeth a slope to allow the collar to slide over the pin.  The tooth I modified is the one that sits over the pin I was trying to push in, of course.  It's hard to describe, and I didn't take a picture of the modification (but I did something similar later, and I took a picture of that).  The modification lets the collar slide over the end of the pin as you push it in.

Eventually, success!

Next up on the docket is to flip the shaft over to install 3rd gear.  Similar to 2nd gear, I cleaned it up and lubed up the roller bearings (which let them stick to the shaft, by the way). This time, though, there is a single spring loaded pin that gets installed before the gear is installed.  Then, the gear slides into place.  Note that you cannot forget a single roller bearing, or you'll have no bearing at all after a short time.  There's lots of them.  I didn't lose any, twice.


Like I said before, I modified this retaining collar to give a tooth some slope to allow it to slide over the pin as the pin is pushed in.  The modification doesn't take away any strength since the collar is twisted to lock it in place with the pin.  The pin I modified is just before the 12:00 position.

It was quite a bit easier to install (heck, given it was impossible before, anything's easier).  The other key was having one of these.  It's a little cheapo pick that I nipped off the end.  The curved section lets you get it under the collar and push in the pin.

In the end, result!

That looks like the hardest part, until I get to the next hardest part... rebuilding the 3rd/4th synchro assembly.  It's got three spring loaded balls that I can't wait to lose all over my garage.
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Cleaning Things

I finished the teardown of the remote housing.  The only thing I'm not going to remove is the linkage because it's been in there forever and I don't want to mess it up.  It's just a little grungy and some degreaser will take care of it.  The transmission is now completely disassembled.


I also did a little cleaning and painting.  The transmission mount is all pretty now.

I also disassembled the master cylinder and cleaned it up.  It needs honing--the bores are still 3/4" and good enough that honing will clean them up (I hope).  I have a rebuild kit.

Finally, I couldn't stand it any more... I cleaned up my Moto-Lita steering wheel.  I had hung it in the garage and 12 years later, it was gross.  It cleaned up nicely, though.  My dad restored my original wood rimmed wheel, so now I'll have two!  Maybe I'll mount one on the passenger's side as a gag.

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Sunday, May 29, 2016

Transmission Takedown, Part 3

Now that the transmission proper is apart, it's time to tackle some cleaning and the remote housing.  But first, the transmission mount.  I think I know why the gearshift was vibrating--the center mount was separated and basically a rubbery, gooey mass.  I can see where the mount got bent when it let go.

After a little quality time in the blasting cabinet and a visit from Big Hammer and his friend Mr. Punch, things look much nicer.  I'll prime and paint the mount before reinstalling the rubber bits.  Boy, I love having that cabinet.

Next, the case.  You won't believe it, but I got the case in the blasting cabinet. I cleaned every mating surface I could reach.  Then, because it was full of oily sand, it got degreased twice and scrubbed, then run through with an engine oil gallery brush, then washed in brake cleaner, and now you can eat off it.  It would be a small meal, though.


I left the patina on the outside since there's a little factory overspray still visible.  That's how they came, apparently.  But all the gunk is gone, gone, gone.  It's ready for reassembly.

I got started on the bottom part of the remote control housing and got it apart, but not cleaned.  There are very few parts here--the speedo drive and the shaft and arm that controls the selector fork rods, and the rear oil seal.  I now know why I always had a little leak out the back (and that isn't a personal problem, no matter what you may have heard)--the oil seal was as hard as a rock.  It needs replacing.  But I'm keeping it, because you never throw anything away until its replacement is fitted.  I heard that from a really wise man once.


Last, but certainly not least, is the upper housing that connects the shift lever to the arm that moves the selector fork rods that move the selector forks that engage the synchros that smoothly connect two gears together and make the engine drive the rear axle.  And that's how you do the skeleton dance.
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Parts Time

Here's everything I need to rebuild the transmission.  Well, almost everything.  The kit I got from Victoria British didn't have the rear oil seal I was supposed to get, so I have to give them a call.  But yay, parts!

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Transmission Takedown, Part 2

After soliciting a little advice from folks on the MG Experience BBS (Oh my God, who remembers what a BBS was?), I sallied forth with the first and third motion shaft teardown.  There were four key items I needed to proceed:
  1. A bearing separator;
  2. A driveshaft yoke;
  3. A big hammer;
  4. A big wrench.
I started with the first motion shaft.  The shaft needed the driveshaft yoke to hold it in place so I could remove the bearing retaining nut.  The big wrench (1 5/16") did its job well.  (A side note on that wrench--I got it on Amazon for $12, and Prime shipping meant I had it in two days.  I mean, jeez, what CAN'T you buy on Amazon?)


Once the nut was out of the way, the bearing separator came into play to, you guessed it, separate the bearing from the shaft.


That was surprisingly easy.  No gear teeth were harmed in the removal of the bearing.

Next up, the third motion shaft.  This guy has the bearing in a plate that fits into the transmission housing.  I decided the easiest thing was to remove the plate, then the bearing.

Time for the big hammer (whom I call "Big Hammer") and the vise.  I sort-of-gently drove the bearing and shaft through the plate, and it came off without a problem.  The plates are not reproduced, so thank goodness.


Nurse, I need a bearing separator--stat!

The thing is, the puller part of the set only had about a 9" depth.  So I got a little creative, and with some threaded rod and grade 8 nuts, I made a really long bearing separator.

And boy, it did the job.

The thing is, the tool was not well constructed.  The separator was cheap and wobbly and already showed significant wear after a single use.  If you buy a bearing separator set, don't go cheap.  Buy a set that has no slack in the retaining bolts (in other words, well machined).  I got away with no damage but I was not pleased, so it went back.  I fully expect to need to buy one again, because tools.

Anyhow, with the bearing gone, I was able to remove the first gear cluster--it just slid off.  I didn't disassemble it to prevent little flying bits from leaving my vicinity.  Removing second gear is a bit of a chore, though.  There is a retaining collar that is held in place with two spring loaded doohickeys.  You have to push one in, then turn the collar, then push the other in, then turn it the rest of the way.  Then, it's not happy to just slide out, so gently tapping on the second gear cluster gets it moving.


Removing the doohickeys and the little bitty baby thrust washers allows the second gear cluster to slide off.  The second gear synchro was stuck in place (which I didn't recall being a problem), but it was only just a bit stuck and came off with a gentle tap or two.



And there you have it.

Here's the inventory of what came out of the inside.  The biggest piece of advice I can offer is to be uber-organized and bag everything.  Throw nothing away until you have fitted its replacement.  And keep everything clean, clean, clean.

Now I just need parts...
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Sunday, May 22, 2016

Deconstructing Tranny

Since it's now too warm to get any meaningful body work done, I figured I would do what I threatened and tear down the transmission. The Haynes manual is really quite descriptive as far as tear down and assembly in this case (usually, it's described as "assembly is the reverse of removal").

I've worked on every part of the Midget to date, except for the transmission. I can't say that any more!

First, I had to clean my workbench.

Then, I put a transmission on it.

Next, I removed the remote control housing.

After that, the side cover. There are a couple of selector plungers that came out with a little help from my air gun.

Next up was the clutch release fork and the front cover. The front cover had never been removed, I suspect. It was tough.

The reverse gear locating pin came next, followed by the selector forks and rods.


The manual says to measure the end float on the laygear (the one that doesn't have selectors and transmits power from the main shaft to the input shaft). This is cleverly done by moving the reverse gear out of the way and measuring the gap between the laygear and the back of the box. Mine measured out to 0.008", when it should be a max of 0.003".  So new thrust washers are needed. I'll have to figure out the right one, but they come in a range of sizes.

EDIT: After measuring with my vernier caliper, it looks like I'll need a .130" washer.

EDIT 2: After measuring the new front thrust washer, I need a .128 washer to bring the endfloat to 0.001" as recommended by many.  Fortunately, I bought one.  It will be close and I may have to do a little work to get things right.  I can always use the old front thrust washer--it's pretty good--but I'd rather replace it.

The most difficult part came next--removing the main shaft (or "third motion shaft"). It has a bearing and a whole bunch of gears on it held in place by a plate that press fits into the case. That was fun. Eventually I ended up clamping a grip wrench to the shaft and tapping on it to extract the plate. But it came out with no damage.

Last was the removal of the reverse gear, the laygear and the input shaft (first motion shaft). The last was easy--remove a retaining clip and lightly tap the shaft into the case, then remove the assembly.

I ended up with a completely stripped gearbox.  Result!

It looks like the main shaft bearing is ok, but I will replace it anyhow. The input shaft bearing is trashed. The roller bearing between the main and input shafts is pretty bad, too. However, everything else looks amazingly good. No debris or flakes in what was left of the fluid or coating the inside of the case. The gears look decent. The box worked well other than that vibration, so I think it will be better than ever when I'm done.

I ordered a rebuild kit from VB that has just about everything I need. I will have to order thrust washers from Moss, though, since it seems VB doesn't carry them.  What the heck. It's just another $250, right?  That pretty much taps me out.  Good thing I got a little birthday money to cover the gap.

Next time, I tear down the main shaft assembly. That should be fun. I'm a little nervous because if I get that wrong it's a real pain to set right, given I would have to remove the engine and gearbox to work on it. But it's just a machine. A working one, even. So I should be able to figure it out.
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Monday, May 16, 2016

The Heat Is On

Well, it's finally summer.  High of 104 over the weekend.  (Oh, wait... it's still mid-May.)  Too hot to work on the Midget in any serious capacity, so I think I'm likely done for the summer with any body work.

My dad and I did pull the transmission and starter off the engine that was in the car, though.  We cleaned 12 years of garage gunk (and a couple years of road gunk) off it, too.

I think I know the cause of a vibration around 50 was, though.  The input and main shaft bearings are deceased.  I've got a good 1/8" play in each, so it's going to be transmission rebuild time.  I think the innards are OK otherwise, since it was quiet and shifted smoothly.

I bet I can manage that over the summer... I do have an air conditioner installed in the garage, but it's not powerful enough to really take down the heat when it's 110 outside.  I wouldn't want to be sanding anyhow with the door closed, either.

But once we did that, we built a shelf and rearranged the garage.  I have a lot more room and the car isn't smashed up against the table saw like it was before, so I'm pretty sure it will survive until fall without getting banged up.

I'm just glad I got as far as I did this spring.  I was hoping to have the car in primer, and I ended up not too far away.  This fall, there will be paint!
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