Master cylinders

[Eric R]

I understand that the P5 3-litre has two master cylinders. At least one is leaking. Can anyone guide me to a source for replacing them. Does one of them usually come with a complete servo unit?

[norvin]

Only one master cylinder on the brakes, so not sure what you mean by two, if it is only the seals gone in the master cylinder you can buy a kit of new seals for it, with the servo brake fliud can be forced into the servo and drawn into the engine which will be burnt off as white smoke. If it is the master I would try and repair it as m/c are not cheap.

[Eric R]

1000 yds after a full service and standing for a week, found I had no brakes! Restorers tell me there are two master cylinders - one is leaking from underneath and the other might well do so after the first one is repaired!
No sign of fluid on the floor so it is suggested that it might have gone into the servo unit - in which case servo and the attached master might need replacing.
I don't have the skills to restore myself. Best option at present seems to be to send the unit to www.pastparts.co.uk who offer to restore for around £90 + Vat so i guess thats where i will have to go.
Thanks once again Norvin.

[norvin]

The part on the vacum unit is not a master cylinder it is the valve body, if you have no leaks that you can see then yes it could be the valve body leaking fluid into the vacum cylinder.
PS. It could be a wheel cylinder leaking but if you had a full service would think they would have taken off the brake drums.

[Eric R]

wheel cylinders and shoes replaced on the service

[Phil Nottingham]

You have the infamous and incredibly unreliable when it ages - Girling Mk2 Servo - replace with later simpler chepaer and better Lockheed as used on teh P5B and P6 see earlier posts on SEARCH and JRW thread!