Page 1 of 1

#1 Oil leak automatic gearbox

Posted: Tue May 01, 2018 8:01 am
by Djerome60
Hi everyone,

after the first 100 miles with my newly restored serie 3 2+2 the little leak i had on my BW 12 is getting bigger. I initially thought it was coming from the oil sump and it's why i have ordered the aluminium conversion kit but i have just found out that the leak is coming from the kickdown solenoid connector.
My question is therefore : can i change the seal of the connector without getting the GB out? I believe that i can get access from the bottom if i remove the valve block? (can i remove the valve block without any specific tools)

Many thanks in advance
Regards
Jérôme

#2 Re: Oil leak automatic gearbox

Posted: Tue May 01, 2018 1:27 pm
by lowact

#3 Re: Oil leak automatic gearbox

Posted: Wed May 02, 2018 3:33 pm
by Djerome60
Many thanks.
I have actually an hard version of this manual but in this case it does not really help.
Nevertheless i found out that the connector mentionned can be accessed from the bottom by removing the oil sump.
I'll do the operation once i would have received the new oil sump and connector seal and i'll post some picture if it can benefit someone else.
Regards
Jérôme

#4 Re: Oil leak automatic gearbox

Posted: Tue May 29, 2018 7:21 am
by Djerome60
Hi everyone,

i found the leak it was indeed coming from the connector but it was not the O ring but the connector itself which was broken.
I fix it with a speacial Loctite sealant as interim solution and works fine.
No more leak.

Image

#5 Re: Oil leak automatic gearbox

Posted: Sat Apr 06, 2024 12:25 pm
by Colin
Hi Guys
This old chestnut again I'm afraid BW12 Auto Gearbox leaking fluid
Have suffered all of the above exactly same as the originator of the thread Dejerome60 - newly rebuilt box 2 new genuine Jaguar cork gaskets etc - new second Hand oil sump - glued the gasket to the sump open a flat surface before fitting - Checked all of the obvious places such as kick down switch etc as shown by Dejerome60 all ok. Used tiger seal - also coated the cork gasket in varnish (apparently a Jaguar bulletin suggests this ??). Now down to last but one resort. Has anybody used the rubber type gasket made out of Duraprene offered by SC Parts. Not cheap at £32.00. (they refer to it as uprated)

Last resort is an aluminium sump circa £1200

https://www.scparts.co.uk/thumbnail/2c/ ... 0x1920.jpg

Asking if anybody has had issues using this uprated seal let me know otherwise I will give it a try and advise the outcome

Thanks Guys

Colin W
S3 V12 73 2+2

#6 Re: Oil leak automatic gearbox

Posted: Sat Apr 06, 2024 7:16 pm
by kashma77
Djerome60 wrote:
Tue May 29, 2018 7:21 am
Hi everyone,

i found the leak it was indeed coming from the connector but it was not the O ring but the connector itself which was broken.
I fix it with a speacial Loctite sealant as interim solution and works fine.
No more leak.


Hello Jérôme,
congrats for fixing the issue, where in france are you from ? maybe we can take a spin together, I live in Annecy :bigrin:
kindly regards
Ralf

#7 Re: Oil leak automatic gearbox

Posted: Sun Apr 07, 2024 8:18 am
by Cavern
Hi
I’ve tried both type of gaskets and have stayed with the cork type using Victor Reinz gasket sealant. Not because of the cost, but found the cork to be adequate when installed correctly.
I have the original unrestored auto transmission with 56000 miles and original sump pan.
I had a slight oil leak on the right hand side which ran along the length of the sump pan gasket edge and would drip onto the right hand exhaust pipe, so I’ve tried both options during this.
I found the kickdown switch had very slight movement on the outside but wasn’t sure if it was an acceptable amount of movement due to “originality”/age as it’s not secured in place and there was little oil under it.
I removed the sump pan, disconnected the electrical connection to it and removed from the casing (easy to do on a ramp). The “o” ring rubber was slightly hard and slightly loose, but not bad for its age.The switch condition was okay so I replaced the seal ring. Fitted a cork gasket with Victor Reinz and it’s been dry since.
Best regards
Mark

#8 Re: Oil leak automatic gearbox

Posted: Sun Apr 07, 2024 9:58 am
by Colin
Hi Guys
Thank very much for responding

Kashma77 - I don't think it is the kick down switch is leaking. I have felt all around and above the sump pan and can see no signs of any fluid running down, however in light of what Mark said I will investigate that again. The box was recently rebuilt so I would assume (probably wrongly) that all of the seals would have been replaced.

Mark - My symptoms are exactly the same as yours RHS of sump drips onto the RH exhaust pipe. The drip appears to develop after shutdown and is a small drip but eventually stops.

The car is still undergoing restoration so I am not able to get it out on the road and get it properly hot so that's not helping as it may seal itself (Wishful thinking)

I'll try the rubber seal with a cork backup as options are running out. I currently have 14 hex bolts and washers securing the sump but I see from the parts manual Page 31.07/26.07 "10729" looks like a flanged bolt which are NLA. I am told that the bolts are UNC 5/16 x 1/2 so I have managed to get some from Westfield fasteners M8 x 12mm stainless these appear to spread the load better than bolt/washer. More often than not the bolts are overtightened and they distort the sump so will need to check that it is flat but I am on my new secondhand sump.

Ill look into the Victor Reinz as well

Thanks again guys will report back

Colin W
S3 V12 1973 2+2

#9 Re: Oil leak automatic gearbox

Posted: Wed Jul 10, 2024 11:59 am
by Colin
Hi Guys
Just wanted to report back and make a confession.
I purchased the duraprene gasket from SC parts and it is indeed bulkier than the cork gaskets but not cheap - I purchased cork gaskets as backup which are cheap.
(Just a note the cork gaskets being supplied these days are dual BW8/BW12 so have an extra bolt hole in 10728/1 not a problem but caused a bit of confusion albeit I didn't use the cork gasket.) The new fasteners I purchased were of course metric so that was a no go. We fitted the duraprene gasket using the victor Reinz sealant - I had someone dress the sump pan which had some minor undulations. All went well left it over the weekend to cure and fthen filled the transmission sump and it still leaked. Now comes the confession - we had already checked the normal leak points such as the solenoid/speedo etc which were all dry but luckily my painter (who is now called Hawkeye) spotted the leak from the oil return pipe angled union which was only finger tight. Once tightened now dry as a bone. I have to say even after being pointed out to me I still could not see the leak but nevertheless it's now cured.) This sump has leaked for 46 years after it was previously reconditioned in 1977 and I now have a dry sump. I probably need to add that the box has been reconditioned again recently when the box was taken out and put back and is where this new problem emanated.

Colin W
1973 V12 S3 2+2