Original Vanagon manual gearbox failures and solutions

[gears]

.
I think the stronger bellhousing is just to avoid cracking, which does happen occasionally when off-roading. It certainly isn't going to help with mainshaft rigidity, as we already have a quill-shaft (2-piece) design, AND we aren't hanging the engine off the bellhousing unsupported (like Type I).

Anyhow, I like the looks of the Go Westy bellhousing. It looks like a quality piece to me.

As for a stronger main case, I believe that this is already in the infancy stage. I expect the final product to be far stronger than even the German aluminum main housings.

Our gun-drilled mainshaft ISN'T going to cure the ball bearing race erosion that we were talking about earlier. I really just put the photo up because we were doing "show & tell".

The oil-fed GT mainshaft will hopefully help with the 4th gear needle bearing "false brinelling" issue, and it will certainly help with the poorly oiled, pathetic rear needle bearing. (This bearing still should be upgraded to Type I.) As we were making mainshafts anyhow, I felt the oiling option should be incorporated. After all, you don't HAVE to oil feed it.

No, the eroding bearing issue has two possible solutions (aside from dumping more oil into the general area as many have already been doing):

1) It's time to return to use of a 4th gear thrust washer, just as Rancho and one or two other shops have been experimenting with. This will add 20% to the surface area contacting the ball bearing race, and just may be a partial solution.

2) Straight-cut 4th gear. This is an almost guaranteed solution. The possible downside is a noisier gear, however, huge strides have been made recently allowing a straight-cut to be reasonably quiet. To be quite honest, our racing tooth profile 4th gears are sometimes noisier than we'd like. So, in the future, we'll probably make a portion of our 4th gears as straight-cut .. just as we've done with Porsche street gears for a number of years. (Virtually all Porsche race gears are straight-cut now.)
https://www.thesamba.com/vw/gallery/pix/1090981.jpg

This will be full circle for me, as the first 091 off-road gearsets I ever experimented with (in 1988) were straight-cut (although not nearly as nice as what I now propose). https://www.thesamba.com/vw/gallery/pix/1129657.jpg

I plan to incorporate all of this into my next transaxle, along with Joe's billet intermediate housing.
_________________
aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

[Pcforno]

Exciting times! Thanks for all your work gears! I assume the new main case will have a larger bore for the type 1 needle bearings. I can’t wait to see the new intermediate housing - I’m guessing it will have direct oiling ports to MS bearing and a better MS retention plate. Will it be available or the general public?
It’s kinda funny, my rebuild is holding up great but lusting after all these new transaxle improvements. Certainly I’ll eventually need a rebuilt and it’s great to know we have some options. Thanks again for all your great work gears👍🏻

[gears]

Probably a cast-in steel bearing section, like early Porsche 915 ..
_________________
aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

[Waldi]

Some interesting pics about
- cleaning factor synthetic oil
- oil circulation
- where the needle bearing gets his oil from
- why a main bearing retainer is necessary
- why you should not use a paper gasket between bearing shield and low gear housing.

Syncro 16 box with 100k km, no failures

[Waldi]

How to diagnose a worn out pinion bearing if you are not sure to hear it while driving.

Put the car on a elevator, drive in through the gears by using the emergency break, record the noice. Make the record visible with a pc.
Share the record to compare with others or compare with a fresh rebuilded box.

Edit:
Even this Syncro box with 270kl with clearly noise on decelarating or driving downhill with engine break, had no pinion damage.

https://youtu.be/T4vpgpRh1as

https://youtu.be/98JvH2gIQao

[Sodo]

[gears]

The mainshaft race that this bearing rides on exhibits too much wear at times. Wear here increased when VW went to smaller needles in '68. The earlier bearing rarely wore the mainshaft excessively.

Tiny needles tend to skid with the more slippery oils, especially at higher rpms. So, conversion engines revved to higher rpms (than the OE 2.1), combined with slippery synthetic lubes, will wear this area more.

Anyhow .. I can't say that I agree it gets "enough" lubrication from oil splash in all instances. Like to rev your engine? Expect to see more wear.
_________________
aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

[candyman]

[gears]

That wouldn't be what I consider high revving. Subaru engines easily rev to 5K, and some folks hold them at high revs going up grades. That's when I'd expect to see added wear (which is one reason I've had gun-drilled mainshafts made).
_________________
aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

[Waldi]

Just to make clear, the main ball bearing has no measurerable wear from 4th.
But the bearing shield has. The wear on the bearing shield is asymetrical, due to lack of bearing retainer. This means also the load from the 4th on the main bearing is asymetrical. Which could lead to more wear on the bearing with more km.

Paul, isnt GL5 oil more slipperly than GL4 ?
I have seen about 5 damaged (pitting) mainshafts on about 200 boxes.
High revs, heat due to to less oil, and high load in 1st with low revs are some reasons which can lead to this. A combination of all this will.
I can just say from my own experiance on my box, that driving 150 km with no oil due to a boken synchronizer G-R and a hole in botton of the lowgear housing, do not destroy anything in the box.
I had 2 broken synchronizers within 200k km driving with a light flywheel on the AAZ. Also all my synchonizers were used but without play when installed.

[Waldi]

The black in the box are not from steel particles but from aging residues in mineral oil.
Like carbon dust.
Same as in black engine oil. Atleast the oil filter cannot filter it out.

[DanHoug]

on my 87 4spd i had the same black coating above the gear oil line. it seemed to be some sort of oxidation and while magnesium oxidation is typically white, there might be something in gear oils that causes a black variant.

interesting article on magnesium oxidation...
https://www.cycleworld.com/2013/09/10/developments-in-preventing-magnesium-corrosion/
_________________
-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[Waldi]

The black is all over the box with mineral oil.

[Waldi]

Don't install this weddle gears into your box


Link


Link

[gears]

The syncro cone on Weddle gears are free-floating on purpose. Not the best design for synchro ring longevity, but not a disaster either. We actually do the same (loose-fitting spline) on synchro-less Porsche dog-box gears.
_________________
aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

[Waldi]

Indeed, spending money for non longlivety trash is not a desaster. If you do it all days long.

[Sodo]

Your video showed the synchronizer cone loose on the splines. It was so loose that it falls off with a light touch. I agree this looks like a quality problem. Have you asked Weddle about it? Maybe they don't know yet.

The synchronizer cone is used only for a short moment to match the gear speed to the hub/shaft speed.
The bronze synchronizer ring is "loose" as well.
Can you explain the problem that looseness at the splines will cause?
_________________


'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[Waldi]

Not only loose but with significant side-play. No need to touch the ring to fall off. Both 3rd and 4th the same.
Thats not only a problem for the synchrorings on in-out-shifting also without shifting there is contact with the synchroring and gear ring. The synchronizers are light not sitting on splines, the gear-ring is heavy.
I see another problem on the behind-grind on the teeth due to the side-play and we all know, ones there is play on splines it becomes fast bigger.
You can here the clack-clack in the vid. Now imagine what happens if the TDI is hammering there.
It would be easy to do the spline exact for shrinking and even better weld it after. But hey, the profit.
I am curious now how Paul gears look in my TDI Sika box after 15k km.
But atleast they were fixed together. And as long i dont feel and hear them, they will be ok.
I see good Synchronrings on 300k km boxes, would be interesting how long they last on this for me not acceptable gears.
My orignal gears in my white synchro have about 450k km.
I am kinda with Paul that it is not as dramatic if they are already installed. Not dramatic nuff for taking them out again as long they work.
I will not discuss further about them.
Its everyones joice.

Edit: to say it more clearly,
If you shift out of the gear you pull the gear ring due to the behind grind against the synchronrings. That means you use them double times as usually.

[westyventures]

Waldi, instead of spending so much time trashing Weddle, WHY NOT CONTACT THEM if you feel there is a problem? Perhaps they are unaware.

[Team WorldTour]

I'm going to step in (it) here for just a second.
I have to offer some defense to Waldi here. True, Gears does have alot of experience, no question.
But Waldi has a made a good name for himself here in Germany. He is known here, and people do respect his work.
I would not dismiss his opinion out of hand.
That being said, please continue.
_________________
1990 Feldjäger Syncro AAZ
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