Has anyone successfully rebuilt a brake master cylinder using the seal kit from superformance? They only have a kit for the later E-series master cylinder however the 3 internal seals are the same on an L-series. I have both master cylinders apart (L-series and E-series) on the bench and both are 7/8" bore as per the workshop manual. The old seals from both master cylinders are around 22.6mm diameter but the new ones are almost 1mm larger plus I'm not crazy on the quality as at least one seal has a noticable offset centre hole. Obviously I'm concerned about the tight fit and the supplied seals are probably for a 23mm master. I also read that the 7/8" seals that are available have poor fit. Is there an alternate known good source or will these be ok? Thanks, Andrew
Yes I did a rebuild using them ... I had real problems bleeding the system , I don't know why ... and generally I could not get the brakes to work correctly .... Eventually I bought a new complete master cylinder and chucked outvote old one ..... Perfect brakes ... I'm not saying it was the seals but as you say the quality is not great ... Actually I have spent many thousands with the U.K. Company and I like them but s lot of stuff is not very good and some is just rubbish or won't fit .. I just bought some rack and pinion stuff .... Wrong size and even wrong threads ...
Thanks. I followed up with my brake rebuild shop, visibly poorly made seals (centre hole offset by ~0.4mm) are no good and he agreed what I have been supplied is likely for a 23mm master cylinder. I'm following some leads on correct seals. Also, there is some info out there on the internet about replacing with cup or lip type seals instead. I was told not to try this, it will fail and the original designers got the rounded seal design right if sized correctly for both shaft and bore.
I had my 308 QV master rebuilt by Apple Hydrolics on Long Island. They will resleve it so you won't have any issues, if you want the original in the car.
Ron Karp sleeving in CA did all mine in stainless sleeves, he's been helping me and they have the correct 7/8" seals available. I was just trying to use up parts I bought some time back... unfortunately now in the bin.
Yep, I fully understand. The problem is the crap that they now offer for rebuild kits makes the $$ saving not worth the time aggravation loss. I would always rebuild my british stuff, but the quality of the stuff just kept getting worse and worse.