Club G40 Forum

Technical => Engine and Transmission => Topic started by: Nick_S on February 14, 2009, 05:42:41 PM

Title: Bargain box?
Post by: Nick_S on February 14, 2009, 05:42:41 PM
I bought a spare gearbox the back end of last year which is apparenlty off a Vento. Now i've only just noticed this might have an LSD fitted, due to the driveshaft flanges both rotate in the same direction when done by hand. It does the same on my ATV avec Gripper LSD, but not on my OE late CEG box.

I've had a look through both filler holes on the boxes and i can see the OE flat head crown wheels bolt heads.

Here is the box off the Vento:

(http://img.photobucket.com/albums/v292/nicksiggy/Speedo1.jpg)

As you can see the oil seal on the flange looks replaced and the sealant between the casing does not look OE type to me.

Could I have found a bargain box with Gemini diff or am i missing something :)

Title: Re: Bargain box?
Post by: hayesey on February 15, 2009, 12:44:05 PM
best bet is to crack it open and see, not hard to seperate the casing halves just a few bolts.
Title: Re: Bargain box?
Post by: Nick_S on February 19, 2009, 08:37:03 PM
Cracked it open today. Looks like a VAG diff, but the crown wheel is rivited on. There are no nuts on the other side of it, just more flat heads. Is this a late modification to the 085 boxes?

(http://img.photobucket.com/albums/v292/nicksiggy/Diff.jpg)

Look at the thickness of the edge of the crown wheel on a pressed on version in Mr Hayes photo.

(http://derby.polog40.co.uk/photos/diff_fitting/diff-3.jpg)

The main oil seal in the bell housing was on its way out, the spring inside it was chewed up and half hanging out. Hopefully only a few quid from the dealers

(http://img.photobucket.com/albums/v292/nicksiggy/Bellhousing.jpg)

Title: Re: Bargain box?
Post by: hayesey on February 19, 2009, 10:08:14 PM
that's weird nick, it looks like a bolted on crown wheel on that side.  Do you have a photo of the other side of it? 

I would say if you can get those rivet things out somehow (they surely must come off one way or another) then the crown wheel could well fit an LSD. 
Title: Re: Bargain box?
Post by: Nick_S on February 19, 2009, 10:12:15 PM
Yeah thats what i thought, if i want to fit an LSD into it i'll have to introduce them to mr tungsten carbide drill bit :D

Reason i got this box as a spare is because it has the same gearing an as an 8P, but with a longer final drive ;D

And for anyone who has not seen where the magnet is located in these gearboxes, it's at the bottom of the box, in the middle next to the crown wheel. You can see it cleaned of swarf and filings in my open box photo.
Title: Re: Bargain box?
Post by: Nick_S on February 22, 2009, 09:52:05 PM
Pics of the diff rivits.

(http://img.photobucket.com/albums/v292/nicksiggy/PICT0086.jpg)

(http://img.photobucket.com/albums/v292/nicksiggy/PICT0088.jpg)

Looks like i'll be seeing how tuff those rivits are sooner rather than later. The diff bearing on the drivers side comes off really easily in your hand. On close inspection, the diff housing is really badly scoured and worn where the bearing sits on. I'll see if i can utilise the diff housing JP race gave me back from my G40 box.

If you count the teeth on this crown wheel, there are 62. An 8P and CEG has 65, ATV has 60.
Title: Re: Bargain box?
Post by: hayesey on February 23, 2009, 09:24:02 AM
what's the code of that box?

Title: Re: Bargain box?
Post by: Nick_S on February 28, 2009, 12:43:31 PM
CHL

Makes me wonder how the mk4 polo box crown wheels are fixed on because this is the same design. ETKA shows nuts and bolts for the diff on this box ???
Title: Re: Bargain box?
Post by: hayesey on February 28, 2009, 08:44:02 PM
well I was reading something just a day or so where someone was saying that the reason mk4/5 boxes fail is those rivets so I guess they are the same.  Apparently the rivets are prone to shearing off and vw sell a "repair kit" which I guess consists of some nuts and bolts.  I still reckon you'll be able to put a diff in that box.
Title: Re: Bargain box?
Post by: neil_dubgt on February 28, 2009, 11:36:29 PM
/\ yeah thats right


thats the final drive yeah? those rivets are the ones that shear puncturing the gearbox casing and draining the oil out!

there upgraded by using stainlesss nuts and bolts opposed to the rivets...that shear  :-\

interesting to see inside..
Title: Re: Bargain box?
Post by: Nick_S on March 01, 2009, 10:37:07 AM
Very interesting. If this is the case then i reckon my late CEG will have the rivits too when i crack it open and i also suspect the late GT gearboxes CEH? will have the rivits. Maybe only the G40 boxes got the nuts and bolts from factory because of motorsport links/uses???
Title: Re: Bargain box?
Post by: Nick_S on March 14, 2009, 07:43:08 PM
Drilled out the rivits and removed the crown wheel earlier.

(http://img.photobucket.com/albums/v292/nicksiggy/Photo-0183.jpg)

Was fairly straight forward if you have some hardened drill bits. I can now fit this to my spare ATV diff housing or an LSD in the future if need be ;D
Title: Re: Bargain box?
Post by: Nick_S on March 20, 2009, 12:48:23 AM
Just read a post on Club Polo about someone thinking their diff bearings are shot. One of the replies posted this link:

http://www.volkswagenspares.com/page.php?page=Gearboxes (http://www.volkswagenspares.com/page.php?page=Gearboxes)

If you scroll down it mentions about these weak factory rivits being a common failure.
Title: Re: Bargain box?
Post by: hayesey on March 20, 2009, 09:16:57 AM
yeah that's the same thing I was thinking about in my earlier reply.  apparently when those rivets shear they are prone to punching a hole through the gearbox casing!