Any Crashbox repair specialist out there ?

[splitpartsunlimited]

anybody could direct me to a Crashbox repair specialist or someone that is familiar with crashbox gearboxes ?

i have some nos ring and pinion sets , that has 31 teeth on the crown and 7 teeth on the pinion ....they didn´t fit on a customer´s split gearbox .

i am completely confused , since i had them in the shelf as "crashbox parts" for years ......

i will really appreciate any info given !!

thank you !

Ricardo
_________________
in my Garage:

1951 crotch cooler split
1971 1302 cabriolet
1981 Mercedes Benz 230 military "Gelandewagen"
2010 Mercedes Benz c200 kompressor touring

[peter schepens]

Ricardo, Hallo;
I have looked in my parts book from 1956. There is part nr 11517141 as non synchro rack an pignon 7x31 and 113517141 for Synchro gear boxes.... crashbox for sure. Maybe there is a difference between the split and oval gear box inner parts or just the difference between synchro and non synchro.
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Zelensis, glassfibre body made in Belgium , disigned and built on a VW platform About 25 body's built.
Hebmuller info wanted for http://www.hebmueller-registry.com/home.html

[Ivan Fuller]

There is an early and a late version. I think a length difference of 2mm in the pinion somewhere. I think they are interchangeable but requires a shim and other parts or modification? - Its about 15 years since I did mine so I cant remember exactly. I think I used a 1954 bus service manual which provided the info on what to do. I'm not near the book right now to refresh. My car is 47.

Peter & I typing at same time. The pinion shaft is very different to look at on a crash box verses syncro box - split case box up to "61?. Bearing in mind standards had crash boxes until then. Its possible the dimension change came about for the later housings?

[splitpartsunlimited]

so what gear box the 7/31 ring and pinion would fit ?
_________________
in my Garage:

1951 crotch cooler split
1971 1302 cabriolet
1981 Mercedes Benz 230 military "Gelandewagen"
2010 Mercedes Benz c200 kompressor touring

[Ivan Fuller]

Ricardo,

Its been a while but I believe 7/31 would be same ratio for crash & later boxes. That's not to say other ratios were not out there.

[Sameleon]

Hi

Have a look to this project. I hope that this will brings more light.
Split ring & pinion can be swapped between kdf ,split & later split case NON sync trans. sync trans known from ovals and early bugs are completely different and cant't be used for split.

http://www.samsgarage.org/projects/1950-brezel-aus-schweden/toc/60-prevodovka-skrin

http://www.samsgarage.org/projects/1950-brezel-aus...iferencial

http://www.samsgarage.org/projects/1950-brezel-aus...kompletace

http://www.samsgarage.org/projects/1950-brezel-aus-schweden/toc/63-prevodovka-osazeni-diferencialu

http://www.samsgarage.org/projects/1950-brezel-aus-schweden/toc/64-prevodovka-razeni-poloosy

http://www.samsgarage.org/projects/1950-brezel-aus...kompletace

[coolairX2]

Hi guys,
I happen to be the customer in question. I thought it might be helpful to see the parts side by side.

https://www.dropbox.com/sh/1tx2bnmsxt9hsrn/AADu1qzMIJP_6iXBvBwq-1COa?dl=0

Even though the ring gear has 31 teeth instead of my 35 it seems to be the same dimensionally. But, the height of the pinion gear looks to put the orientation of the gears in a different location. So I would say it is not a drop in replacement. I would love to know if I can use this piece.

-Craig

[Bruce]

[johnshenry]

I had Bill Capatch rebuild my '51 crash case in Arizona. Arizona Transaxle. Haven't used it in my '57 yet, but he seems to be highly regarded and did good work....
_________________
John Henry

'57 Deluxe
'56 Single Cab

[Ivan Fuller]

Ricardo,
The photos confirm you do have a crash box crown wheel & pinion.

Sameleon has some good reference photos of the procedure required to set up the clearances required. In his case perhaps just checking.

My old friend & VW trained mechanic said to me that they rarely had to change any shims when doing a plain bearing replacement - which was often with pinion bearings only lasting 20-30000 km. (He showed me how to jam the axle on the bench and spin the box up by hand - you can tell even before it goes in the car if its going to whine).

However - changing for a new crown wheel & pinion is NEVER a bolt in replacement. The setup procedure must be followed or it will be noisy and or smash itself.

The tolerances are etched onto the parts and procedure in the factory manual as shown. The factory tools help but it is possible to do it without them or the etchings albeit a lot more time consuming.

When you get the factory manual if you cannot follow what they are saying it really would pay to have someone do the work who can. As mentioned the early factory manuals document the two versions length difference and what to do. I also expect they will clarify ratio differences.

Note on Samelons photos that the drive pins/dogs are getting worn - this will ultimately cause the box to jump out of gear. (something in the back of my mind is telling me these pins and carrier are different in the two versions - 71 & 73mm perhaps). I had a spare set made all hardened correctly- might be able to have my friend find them if you need but I think they are available.

It would pay to research the different ratios. 7/31 is same as later beetle and slightly higher geared - I had a 54 box in my split for a while and it was fine although I had 1200cc Pistons. It may be a bus/beetle thing as the bus has reduction boxes. Sorry I am away from all of my manuals now and cant check for you.

[Sameleon]

Hi Ivan

Pins are not worn, this is the later midifications with grinded ends. KDF and early split has smooth ones, later with grinded ends for better shift 3th and 4th gear.

In the other hand. On my crashbox posted above, there is mixed setup used (same as Richardo has).

New style pinion with small groove for securing bearings and old style 3nd gear (without grove) and old style bearing.

Differences between old & new style pinion described here. Old one on the left, new on the right page.

[coolairX2]

So as I understand it the 7/31 gear set is a later part BUT can be used in a crashbox (which has a 8/35 gear)?

Does it require machining, if so can someone elaborate? Don't think my transmission shop is capable in modifying it.

If I can use this 7/31 gear I would like to use it as I have it in hand. But, I don't want to take the chance and work with it and lose my chance to return it in the same shape.

-Craig

[Ivan Fuller]

Samelon,
That's the pictures in the manual! You can see the extra shim behind the bearing. My box was a 47 didn't have the stepped dogs. The other 47 in NZ jumped out of gear and the old guy changed them out probably in the '60s or early 70's. Mine were definitely starting to wear so we made new ones. Its also a bit of a mix of original and later bits I got at Bad Camberg. Also someone was in there before me and I seem to recall it had the later pinion but it was not set up properly. Things were not so easy then - internet was only just starting to take off. Interesting VW made the modification on the pins. Its so long I cant remember if we did this. 3rd to 4th is easy. 3rd to 2nd not so happy if the rpm not right.

Coolair do you have access to a service manual from the early '50s? The information is relatively straight forward to follow if you do. There is no machining of the case, probably a hard shim to make.You will most likely need a selection of diff side shims and pinion shims. These could be made or salvaged from later box. Samelon are the pins and carrier different?

Ivan.

[coolairX2]

Unfortunately I only have a later manual. If it is only a shim I suppose these could be made. The shop looking at it has a lot of experience just not VW experience and they don't have a ready selection of old trans parts.

I will bring it to them to see if they could make it work. Ideally I could talk to someone who has retrofitted this later part.
It seems like it would be a stronger part as the teeth are beefier and could better handle the load that the Okrasa is putting out

Thanks for the info guys

[Sameleon]

Ivan, carrier and pins with same dimensions across all years. Important is that pins are in excellent condition and carrier as well. If not, shifting is not so smooth as can be.

Here is my part of the NOS crashbox collection. Left side with new style pins, right side with old style. This is not rust, this is transport wax on it.

[splitjunkie]

My early 70's parts book lists

111 517 141 as Ring Gear and Drive Pinion Unit 7:31 Non Synchromesh

113 517 141 B as Ring Gear and Drive Pinion Unit 7:31 Synchromesh

7:31 is the only gear ratio listed for the split case transmissions. Later tunnel case transmissions had 7:35 but there was a 181 part number that had 7:31.

Your R&P is for a split case non synchro transmission as it has the proper splines and oil groves.

I think they made the gears slightly larger at some point for the split case transmissions so it should still fit but as was previously stated a proper setup will be required to have it function correctly.

_________________
Chris

You know, a lot of these scratches will buff right out... Jerry Seinfeld

[coolairX2]

Thanks for the information.

As far as I can tell when the trans was originally rebuilt by BBT they used a later ring & pinion as it is a 8/35 gear set.

As stated I should have a 7/31 gear set. I called Arizona transaxle and Bill cracked an original crash box open and it has a 7/31 gear set.

So it seems I should have the 7/31 gear set and mine is non original. Given that it should fit maybe with some original shims .

My transmission shop may not be able to handle doing this as they are not a VW shop though they have setup transaxles.

[splitjunkie]

spend the extra money and get someone who really knows these transaxles to do the rebuild.
_________________
Chris

You know, a lot of these scratches will buff right out... Jerry Seinfeld

[Ivan Fuller]

Not sure if this is a stupid question - Are you sure you have a crash transmission.
Can you downshift from 4th to 3rd or 3rd to 2nd with double de clutch.
If it has 8:35 pinion and this part is not listed as an option.....

[splitjunkie]