02J leaking between cases

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
I'd thought that I'd posted something about this some time back but am not finding it.

Planning on doing a clutch change on the wife's car: 2003 Golf. When we'd gotten it from her son (we'd bought it for him and then we got it back) I'd noticed a leak from the transmission. It's not a bad leak, but it's not one that appears to be common (I've scoured the Internet and haven't found anyone having a similar leak). We bought this car from the original owner; he'd had the clutch replaced at some point (not documented other than I have a receipt for the clutch- LUK; pretty sure it's not the stock clutch because the car has a Stage 3 tune and DLC1019s). Means that someone messed with it: I've already found traces of some less than impressive wrenching by a professional!

The leak is coming from where the transmission case and bell housing case come together, right near the drain plug. It's NOT from any of the seals. I applied some more toque to the housing bolts but that didn't help: likely tightened more than they should have been but I don't think it's problematic.

I don't want to yank things and be caught flatfooted. I am wanting to have plans in place for various scenarios.

One option is that I'd have to swap for a rebuilt unit. I'd prefer to avoid this because the current transmission shifts flawlessly and the wife is very happy with it (she hates my car- 2nd gear synchro is hammered from a PO).

Another option is to seal things up but I am at a loss as to how this would be done. I cleaned off the bottom and put some sealer on the outside to try and contain the leak: I haven't checked since then because there's nothing I could do about it if it didn't help. There is no sealant that I've been able to detect from the factory (on any of the cars that I've had). However, looking at one rebuilder (first one popping up on a search- no endorsement) I see that they DO use sealer. Someone's rebuild could as readily leak as a reseal by myself: parts costs are less an issue than TIME- I don't want to face it leaking after getting everything back together.

Will be doing the clutch later this summer. Initially I'd put it off because I only wanted to tackle the suspension refresh. I figured that the clutch could wait. But there's signs that the clutch might be starting to slip (as she reports). I'll likely be putting in an SB Stage II Daily: German Cascade Auto doesn't appear to carry my DC Stage 1 clutch anymore- I LOVE that clutch and would put it in her car in an instant.

Not sure that pictures would do anything to help elaborate on this: getting pics on this site is horrendous anyway.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
It is a mated surface, with some sealant used from the factory.

Not very common, or at least not anything beyond some really slow seepage over a long time. If you are 100% certain it is coming from there, then the only way to fix it would be to take the transmission out, and take it apart, clean it up, and reseal it.

The sealant used is specific: the part number is AMV-188-200-03 but I have used the same AC-Delco brand assembly stuff I use on engine oil pans and sealing flanges and it seems to work just fine.
 
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UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
Yeah, that's what I figured would be required, which is why I was waiting to put it off until I did the clutch.


What's the most appropriate/best sealer to use?
 

Mongler98

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Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
Check fluid level. If it's still close enough, just up the service fluid change on it or keep an eye in its level each oil change. I'd leave it. It's a lot of work to pop open an O2J with specialty tools and pullers required. Not worth the hassle unless its leaking a puddle when you park it.
 

jimbote

Certified Volkswagen Nut
Joined
Jul 10, 2006
Location
spiral arm, milky way (aka central NC)
TDI
Tacoma 4x4 converted to TDI
once the trans is out it's about an hour job to split the case and reseal. Use ultra grey, honda bond, yamabond or similar. Remove and clean the magnet while you're in there.
 

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
Will I need any special tools?
 

Mongler98

Top Post Dawg
Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
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UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
I didn't figure it was a TOTAL rebuild: I have a document for that. I was figuring a simple "YES" or "NO." I may opt to farm this out to a local trusted transmission shop.
 

Mongler98

Top Post Dawg
Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
I didn't figure it was a TOTAL rebuild: I have a document for that. I was figuring a simple "YES" or "NO." I may opt to farm this out to a local trusted transmission shop.
1st video shows how he split the case.
You can stop there and put it back togeather
Imo I would out a LSD in there with bolts and replace the synchro and give the entire thing a cleaning. Why not go full out and basically have a new trans. Pulling the trans out and putting it back in is most of the work, I do agree there. But you will find it just takes time unless you are fimilure with this stuff.
 
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