Dummy Learns Transaxle

[Clatter]

[Clatter]

Something else I'm learning here with all of my "This box had this part and the that box had that part" stuff..

A "good core" as in a never-rebuilt factory transaxle, or one rebuilt to original, is rare these days.

None of my four transaxles had a good core to just rebuild.
Three had been rebuilt with parts from different boxes.
The only one that hadn't was wasted..

As Craigslist, or friends, or junk cars, are our only source of cores, it's going to be a crap-shoot.

You'll have to know what you're looking at, unfortunately, because the last guy might have gotten it wrong.
_________________
Bus Motor Build

What’s That Noise?!?

[Lingwendil]

Leave it here!

I really appreciate the context of the teardown and parts comparison leading up to it all.
_________________
73 super beetle thread http://www.thesamba.com/vw/forum/viewtopic.php?t=649622 Back on the Road!

Modify your Kadrons for SVDA http://www.thesamba.com/vw/forum/viewtopic.php?p=8115884#8115884

Cast iron VJU4BR8 SVDA reference thread- https://www.thesamba.com/vw/forum/viewtopic.php?t=...mp;start=0

Need replacement filters for original Kadron aircleaners? WIX #42087 is a perfect fit, as is Napa Gold #2087!

[airschooled]

I look forward to reading more. As a co-dummy, it’s easy to sift through the noise.

I’ll be doing this next month, so keep up the mistakes, er, learned lessons!
Robbie
_________________
Learn how your vintage VW works. And why it doesn't!
One-on-one tech help for your Volkswagen:
www.airschooled.com

[Clatter]

This Saturday morning we had a great lemon crepe breakfast with blueberries and..



Pushed forward a bit with a quick overhaul of the "failed rebuild" trans;
Noodling around and learning how these things go..


Before, it was interesting that they had installed a retaining bolt against the mainshaft bearing outer race:

Now i know why - bearing was loose in the gear carrier and fell right out.
Because the other swing trans had a tight mainshaft bearing i liked it better.
Knocking out detent plugs by just tapping them thru with a drift is SO easy!
Duh.

They did re-bush one of the shift rail bores, though..
Makes me think tight shift rail bores are more important than tight mainshaft bearings?
You can retain a loose mainshaft bearing with a plate or a bolt, so no big deal..?
Or is this just a 'cheap rebuild' thing?
I'm guessing any good rebuild would have the mainshaft race tight in the gear carrier..


Having a chance to see the fit of different shift rail bores is interesting.

Some of them are SO loose!

Moving on with the build, rear little mainshaft bearing was crunchy feeling - like it had dirt in it.
Bearing had been driven in by the cage and crushed against the rollers.

Took my best set of used carrier bearings and made 'setup bearings' out of them.
This way i can do easier initial setup of shims for preload of carrier bearings and R/P backlash.
OD of races got sanded down on a belt sander so they go in/out of the side covers easily.
ID of roller bearings got opened up with a little flap-wheel so they slide on/off diff snouts.
Cleaned up and ready to start playing diff.

Tried to figure out a way to lock spiders for checking backlash.
Tim's book says a piece of paper, or..?
I dreamed of jamming some copper house wire in there and leaving a bit sticking out the hole.
That way you wouldn't have to disassemble the diff to retrieve these after setup, just yank the wire out.

Fail.
Anyone have a slick trick for taking slop out of a diff?
PITA completely apart/together..



Stabbed the pinion shaft for an initial check of case fit and R&P.
Heat gun took forever got me nowhere.
Couple of halogen painter's lights did the trick and then some.
Just a few minutes and the pinion slid right in..

Started fiddling with making a backlash tool.
Stabbed some 'baseline guess' shims in and looked at numbers.

Fun to fiddle a bit and figure things out.

Carrier bearing shims are $10/ea. at Weddle so i didn't just order one of each.
Have some ideas for the shims i need now, so hopefully we'll get some numbers that make sense next time.


All in all, this is looking quite possible...
_________________
Bus Motor Build

What’s That Noise?!?

[nsracing]

The carrier needs to be re-bushed. Almost all of them need that done. It is rare to see a carrier not worn. The bores wobble out on the outer -as the springs push against the shafts, the distal side of the bores wear out.

I have posted in my gallery when I rebushed them years back.

but here they are...

[nsracing]

I used bronze earlier in the projects. But I found that aircraft aluminum material works good too... 7075 T6 Alum.

It is a little lathe work and ream job.

Oh..and I made a tool for installing the balls in a second without fucking up the bores.

[Clatter]

Thanks for the detailed reply, Nick.

Seems like, if you had a handful of the bushings,
All you would need is a couple of reamers and a drill press?

Maybe a drill bit and two reamers?

At $50 no core it seems like a no-brainer to get a bushed gear carrier:
https://www.thesamba.com/vw/classifieds/detail.php?id=2346072

Until you do a few of these boxes;
Then you coulda bought a couple of reamers and be all set forever.


On that note,
I found a smoking gun..
Weddle says you need to have your mainshaft bearing race tight in the gear carrier.
A loose mainshaft bearing is No Bueno - retainer plate/bolt or not.
Here in the instructions for the plate:
https://weddleindustries.com/sites/weddleindustries.com/files/downloads/9371-INST.pdf
"2. Check to see that the mainshaft bearing fits tightly in the gear carrier housing. If the mainshaft bearing is even slightly loose, the gear carrier housing should be repaired or replaced with a refurbished unit."


Unless, of course, you're trying to turn around a cheap rebuild at a good price.
_________________
Bus Motor Build

What’s That Noise?!?

[Clatter]

NLA!!
Those words we hate to hear..


Rear mainshaft bearing.
Guess i can just use the bashed one - it'll probably live for a while.
https://weddleindustries.com/products/113-311-125/113-311-125


Snap-ring at the end of the mainshaft..
https://weddleindustries.com/products/004-311-317/004-311-317
Bible says it's to be replaced every time.
Dished washer presses on it and tries to work it loose.
Failed Rebuild trans here it popped off.
Saw somewhere the groove in the shaft can get worn or rounded - ruins the mainshaft.
Plus, they fly off and disappear!
Do we even want a used one that slipped and rounded the edge in the process?


What do we do now if there's no more mainshaft circlips?
Buy a Honda?
_________________
Bus Motor Build

What’s That Noise?!?

[nsracing]

If the bearing bores are loose, then something else you need to fix too.

What I have done before when time-crunch came for racing trans and no other parts were available, I re-machined the bores to accomodate a feeler gauge material, trimmed to size and pressed the old bearing in there -worked really good too. YOu can add retaining bolts/washer if you like. But the bearing press-fit has to be present..or the bearing will just wobble out.

But...you gotta know how much to machine off and still maintain a proper press-fit for the bearing. If you don't have a mill and boring tools kind of moot point.

The beauty of having machines is you can adapt pretty much anything you want.

How far do you want to go into this hobby??

[modok]

"Loose" or "not loose".
How loose is loose?

These things either have a clearance or an amount of press fit.
And to determine that you have to MEASURE the bearing and the hole.
if you just put a few punch marks in the bore then the bearing fits tight......? That will fool a lot of people but that's now how it works.

But if loose is "loose enough to move around" then most of these nosecone side mainshaft bearings are loose, because they are wearing into the nosecone in the thrust direction. Find me a nosecone that ISN"T worn there! Maybe it exists? I don't know I'm not an expert
So does that mean that all need to be fixed immediately? Surely not.

You will have to find your own "service limit" for how loose is too loose.


A great rule of thumb is .001 per 1
Either as a healthy press fit for a non moving part or a good clearance for a moving part. If there is no specification then that's what I'd go with.

do you want to be a "transmission builder" or a "transmission mechanic?"
If you aren't your own machinist then you will need to fine one.

[nsracing]

The mainshaft nose bearing barely got press-fit in it from the factory. I am thinking it needs a little more. With all the engine mods we do now, the tranny has barely got a look over and left behind expected to keep up w/ more power and abuse.

People neglect the tranny all the time. Back in the day, I made modified Liberty-pro style rings for my drag trans. They sported thicker teeth w/ hardened tooth faces. After a whole afternoon of drag racing, I will teardown the trans and see how the rings were holding up. Pretty soon, I had this idea only the 1st/2nd needed the Liberty-Pro rings and kept the 3rd/4th w/ synchros.

Trans are fun to do if you have the tools and machines to back it up. But it is frustrating to me if something needs done and I don't have the tool for it. But that is all before I had my machinetools.

Now, it is just matter of finding time to go in the garage and be dirty. I am so busy at work. I am happy that people still have the time to tinker.

Clatter - keep at it. You will find your groove or comfort zone.

When I started w/ trans, Mr. Long (Long Enterprises) sent me a small crate of rings and bearings and stuff. He explained to me where all them metals went in the trans.

[Clatter]

Thanks for sharing the wisdom, gents.

I am really fortunate to have worked in a machine shop for a few years.
At least i have a feel for fits and whatnot,
And can measure if inclined to do so - like Modok says.
While some are true experts at fitting things into holes,
There is a lot to be said about checking a fit by feel.
That's what gauge pins are for, right?


A couple of good friends close by own lathes.
One is a hooptie with not much good tooling,
But another is pretty nice, even though the guy isn't a machinist.
Seems that basic facing is mostly what needs done, so no matter.

Additionally, i just found a guy who is a solo prototype guy with a nice shop.
Unlike most of these places, he'll do little dumb jobs for $20(!)
He's a block away from the kids' school and starts early.
Can pick up/drop off and not be late to work(!)
Because none of my friend lathes are small and have a spindle stop,
Got a set of spacers for my trans jig (to do early 4-bolt pinion style) way within .001".

Also, having him do a whole slew of pinion 3rd gear snap rings on the surface grinder about .002" different from each other.

So that's my solution right now for dealing with the inevitable machining operations that arise.
Yes, it would be FAR nicer to just turn around and whittle off a thou or two as i go along right there at home,
But,
Alas,
Until the right deal comes along on an old surface grinder or lathe, I'll have to get by like this for now.
_________________
Bus Motor Build

What’s That Noise?!?

[Clatter]

As for gear carriers, I'm coming to figure out what the deal is and how it goes.


Many have tooled up to do shift rail bushings because that's the most common repair needed and also easiest to do.
It only requires a couple of reamers, some bushings, and away you go.


The job of tightening up mainshaft bearing bores is a different deal altogether;
Likely involving a jig-bore or expensive tooling.

With type 1 transaxles, there seem to still be good core gear carriers around - good meaning mainshaft bearing bores still an interference fit to a new bearing.

With 091/094 Bus/Vanagon transaxles, the gear carriers are more precious (and more abused) so it's worth it to tool up and sleeve mainshaft bearing bores.
Go Westy does this, for example; dig also their end-play shim.
https://www.gowesty.com/product/transaxle-drivetrain/23511/gear-carrier-?v=

Weddle seems to just go straight to an aftermarket aluminum gear carrier.
All of their remanufactured 091 gear carriers are out of stock..
As long as the machining accuracy on these aftermarket gear carriers is good, it seems a better way to go?
https://weddleindustries.com/products/6384/6384



With type 1 gear carriers on a cheap rebuild like we have here, the results are fairly predictable if you look at the market right now.
A guy like Rich Roberts, who is selling gear carriers with the shift rail holes re-bushed, he'll take the time to find gear carrier cores with a tight mainshaft bearing bore,
because he's selling for money and his customers are likely to care.
You would probably find something similar in a high-quality rebuild going into a built performance box from the big builders.
They are likely to be back apart for inspection or repairs, and people are paying a premium price.

In most of your major rebuild houses, trying to turn out a bunch of stock rebuilds for a good price,
They will sleeve the shift rail bores, but if the mainshaft bearing isn't tight, they will go ahead and put the thing together and sell it.
You can put in a bolt or a plate to help retain it, maybe some loc-tite or some peening, and away you go.
Most stock rebuilds don't have high demands or do a lot of miles these days anyway.


So there you have it..
If you really care, try and find a gear carrier with a tight mainshaft bearing bore.
If you're just slamming it together, a little loose on the mainshaft bearing isn't the end of the world.
_________________
Bus Motor Build

What’s That Noise?!?

[Clatter]

More Drivel!

SWMBO had us in the crawlspace all weekend sealing up ductwork,
But i was thinking about transaxles the whole time.
I'll get to MCM one way or another - but until then doing what i can.

She might be a Big Badass Boss most of the time,
But how many of you have a girl that will allow this?

Here's something I'm learning that is valuable;
What exactly you might get if you order a cheap stock rebuild from a "Big LA rebuilder".

Scott didn't exactly say it outright ( )
But really,
What you can get is a carefully-selected assortment of the WORST parts.

Case in point; our example here - the "Failed Rebuild";
Such a crappy collection it didn't even work..

Many places advertise new pinion and mainshaft bearings,
And here that was true.
It had a new China mainshaft bearing, and a new pinion bearing - that i didn't see any markings.


Looking again at the pinion bearing area,
I now know what it is we got here; A "worst" collection of parts.
3.88 ring n' pinions are prized over 4.12s.
People like the earlier mainshafts with the nut on the end.
Later pinion nuts are stronger and have bigger shims.
Steel-cage rollers are wider and stronger.
Basically what we have here is a mishmash of parts all selected for their UN-desirability.

Had a later nut, nice new shim assortment, and some earlier steel-caged rollers,
So decided to dig in.

Red lock-tite was used so the torch came out.

Had to use a BFH on Tim's tool to knock it loose;
Kind of like one of those wacker tools for axle nuts.
Good on the last builder that it was tight at least..
Here the new nut is coming home.
Gave it 188 ft. lbs and some red lock-tite for good measure.

Since the pinion bearing was a new one and installed i decided to leave it in place.
One thing that bugged me was that the clearance to 1st gear was crooked,
So i did this step that they likely skipped - pressing it all home.

After selecting some better gears and shims,
got .008" for 1st and .006" for 2nd,
And the 3rd gear snap ring went on tight and right.
Used a blunt chisel to drift it easily home.

That's better.
Now at least i got the better parts i have here in-place,
And i know the nut is tight and clearances right.


_________________
Bus Motor Build

What’s That Noise?!?

[Clatter]

Ah the teeth..
We've all woken up from a bad night out drinking with a broken tooth or two, eh?

Here's what Rick Long had to say about the subject:

He was selling his re-machined sliders, but why?
How legit a move is it to just break off the fat teeth?


Here on the Failed Rebuild, the fat teeth are broken off,
But the skinny ones ain't lookin' so fine either!

This gear from my stash was looking a bit marginal.
Any of you guys care to comment about this one?
Time to break these fat teeth off?
Looks like it might be ready to jump out of gear to me..

This one was the best i had so i used it.
Would this be considered "good used"?
How good used is it?

Anyways,
If one of you guys who knows these things could comment,
I'd be very appreciative.

Here's one of those scenarios where experience plays in.
How good is good or bad is bad??

_________________
Bus Motor Build

What’s That Noise?!?

[Clatter]

Once the case came out of the dishwasher i gave it some rattle bomb.
Just like Scott says to..

Because i don't have any fancy pinion tools,
Or even one of those expensive continuous inch-pound wrenches..
I'm going to have to be setting up the diff by feel and cover lift-off.

And since the cover doesn't just lift off,
Was thinking it might be OK to slightly sand down a little along the inside of where the cover interferes?

Now i know the o-ring seals it there plus we can glue it up,
But,
The cover needs to locate tightly, right?
Can't have any movement of the cover to case..

Any of you guys use a setup cover clearanced like above for checking diff turning/preload?
How consistent are the dimensions from one cover to the next?

Guess you could use a setup cover, feel the turning torque,
then switch to your final cover and make sure it felt the same.?

How do you guys do it?
_________________
Bus Motor Build

What’s That Noise?!?

[Clatter]

As much as a newbie would like to eliminate using "feel" for turning torque..

It's pretty tough finding a torque wrench that will accurately measure such small amounts.
At least without spending a ton..
https://www.toolsource.com/dial-wrenches-14-drive-...13708.html
_________________
Bus Motor Build

What’s That Noise?!?

[modok]

Put it together with .010 shims (or some other size as needed) in the gap, measure the end play with a dial indicator, do math

Or you could tighten it, then back off the nuts, then measure the gap

[Clatter]