Practically Classics Forum

Hello All
I have just fitted new seals to both the master and slave cylinders on my 1967 anglia 105e after fitting I bled the system using a gunsons easybleed and every thing worked ok,whilst sitting in traffic in neutral last week I idly rested my foot gently on the clutch pedal and to my surprise it sank to the floor with absolutely no resistance whatsoever yet when the clutch was sharply depressed as you would do when changing gear or pulling away it was fine.I checked the reservior and there was no loss of fluid and when I got home I bled the system again using the easy bleed and when no air came out the old fashioned way with an assistant in the car no air came out that time either. Again when I pull away or change gear its fine but if I slowly and gently press down on the clutch pedal it just sinks to the floor.Obviously it shouldn't do this and if I hadn't fitted new seals and bled the system 3 times I would have said it was air in the system or weak seals,should I strip down both cylinders again or am i misssing something obvious and not connected to either here?

let me know what you think.

Keith.

Hi Keith,
Like you say, it sounds like something just isn't sealing well. I'm not familiar with your vehicle, but is it possible that you fitted a seal the wrong way around? What condition were the cylinders in when you stripped it all?

What happens if you put it in gear and hold your foot down on the clutch? Does the fluid eventually leak past and you start moving?

Paul.

Had the same problem wth brake MC on a jag - very scary Brakes ok with firm push but with gentle pressure, pedal would sometimes go to floor.
I didn't muck about and bought a remanufactured cylinder - did strip the old unit but it was a yucky coroded mess, the bore was pitted, probably porus and that was the culprit I rekon.
A NOS or recon unit should be cheap enough for an anglebox I would think

Wicksy wrote:....A NOS or recon unit should be cheap enough for an anglebox I would think

Bog-stock Girling CV, available absolutely split new for well under £20 from MM4x4. There's no need to faff on with old stock or "reconditioned".

I can put my foot on the clutch and leave it in gear for as long as I can be bothered and it doesn't go anywhere,I have re-built loads of cylinders in the past and would like to think that I wouldn't make such a basic mistake as putting the seal in the wrong way around,anyway I'm sure if the seal was in backwards then there would be quite a lot of fluid leakage into the car if it was the master cylinder and as I said I haven't lost any fluid yet although i did notice today that the clutch engagement has become noticably harsher and I nearly stalled it a couple of times as a result.Do you think this is a symptom of master cylinder problems ie a worn bore rather than the slave cylinder and should I bite the bullet and buy a completely new master cylinder? I would hate to get one and its still no better,this is a really weird problem and makes no sense to simple ole me!

hi the small seal on the end of the piston is a supposed to seal the resevoir when the pedal is pressed if this is not sealing the fluid will return to the resevoir , it sounds like it works when pressed quickly as it seals and holds under load but leaks under gradual pressure , is the thin spring washer behind the seal in place and ok , i hope this may help

Got a brand new master cylinder off ebay for £19.95 fitted it and problem solved,the original was weeping slightly from the big seal not enough to noticably show a drop in fluid so I guess it was a worn bore,should have got a new one in the first place!

Cheers everybody, Keith.