RHD Clutch Master Cylinder 12/86 Car - problems!

Post here for mechanical and engine topics such as fuel issues, transmission problems, rough idle, exhaust, electrical issues, etc

Moderators: GRNSHRK, ron, bfons

Post Reply
Pod
Platinum Member
Platinum Member
Posts: 4492
Joined: Tue Mar 16, 2010 8:32 pm
Location: usually in the barn, Kent, England.

RHD Clutch Master Cylinder 12/86 Car - problems!

Post by Pod »

I've recently bought a 12/86 635CSi manual car with an LPG conversion. The clutch master cylinder is leaking, so I bought another + slave. I was so happy to find that I was able to remove it easily - the hydraulic line flare nut was no problem at all!

Then the problems started. The replacement is more than 2" longer than the one I removed and will not fit as it will impact upon the rear of the engine. If you look at the photo attached, you will note that the original cylinder has an extension piece before the hydraulic line is attached. However, upon looking up the schematics (and many adverts) on-line, I can see that the part supplied is "correct". So I presume the CMC fitted to my car was only fitted to the relatively small number of (later) RHD cars manufactured. Maybe BMW used a CMC for another model and adapted it? I've searched, but can find none listed for BMW models with this shorter cylinder - they all appear to be identical to the longer one I purchased.

Dimensions-wise the original CMC is c.165mm long, including the extension at some 40mm. The replacement is c.218mm long.

Has anybody else come across this and if so, how did you resolve the problem? Did you find a part to fit? I've done a search on the forum to no avail :(

I've thought of cutting down the new CMC and drilling/tapping a thread. This will not be particularly easy, but may be the only way to get a new CMC in situ. I'd rather look for an easier solution :wink: (BTW, I do not think the original CMC can be rebuilt due to amount of corrosion in the bore).

I've looked at a late S1 car, which has a 90 degree elbow on the end for the flare nut, but it is located onto the firewall, but inside the footwell, by two bolts to a flange and not by the 10mm bolts running parallel to the steering column. An early S2 car has the CMC mounted on the outside of the firewall, so that's different as well!

If other members with RHD manual cars have had similar problems in finding a replacement, maybe I should consider having a batch of these longer CMCs shortened?
Attachments
CIMG6066.JPG
CIMG6066.JPG (1022.16 KiB) Viewed 1412 times
CIMG6065.JPG
CIMG6065.JPG (1 MiB) Viewed 1412 times
Post Reply