Brake master cylinder seals

The smile is wearing rather him now … I’ve just spent an hour struggling refit the piston into the brake master cylinder (single system) only to eventually get the piston into the bore but leaving a sliver of rubber seal behind,
now this is the second attempt with new seals since the weekend ending with the same result.
This is a job I’ve done several times on the Elan and also on other cars and I’ve never had this issue before, the last time on the Elan several years ago was very simple … and I can confirm everything was lubricated better than the inmates in a Nevada cat house.
The previous seal kit came from SJS, this latest one from Paul Matty but looking at the packaging etc. I suspect they are the same supplier.
I’m starting to wonder if there’s a batch of slightly oversize seals out there.

Has anyone had similar issues recently and does anyone have a set of recently purchased seals to obtain measurements from.
Going to have a chat with the two companies mentioned in the morning.

I had a problem with a clutch master cylinder kit purchased from SJS a couple of years ago, not with the piston seal but with the dust cover which was too stiff and inflexible to stretch over the fixed clevis on the pushrod without splitting. Got a refund from SJS and bought a kit from Demon Tweeks it’s marked Girling and made by TRW. No issues with that but it was more expensive … I guess you get what you pay for.

demon-tweeks.com/uk/girling … aign=85386

Hi,
You really shouldn’t be struggling so I would guess there is something very basic wrong like the seal is the incorrect size or it is contaminated.

Regards
Steve