Brake fluid in servo

[Leekade]

Hi

I know there are some comments on the internet about this but I wanted to test consensus on my problem.

After suffering pretty much non-working rear brakes, I took off the servo and hydraulic pushrod housing and replaced the seals with SNG’s repair kit. As per the WSM, I attempted to remove the pushrod and really struggled as the seal at the servo end of the pushrod had crudded up. I eventually removed both pistons and meticulously replaced all of the parts and seals for which replacements were in the kit.

The servo and hydraulic pushrod/shuttle housing were refitted. When bleeding the brakes, the fluid in the reservoir quickly disappeared. On removing the servo again, there was a pool of brake fluid spring-side. This was cleared, pistons stripped again to check for errors on assembly (there were none) and the unit was refitted.

The brakes were in the process of being bled again and the same thing has happened.

I would point out that the PDWA had previously been stripped and reassembled with new o rings.

Would this suggest that the new seals are to blame?

Cheers

Adrian

[Leekade]

I’ve answered my own question - in spite of looking at the diagram countless times, I hadn’t noticed (or read about) a small bearing assembly at the end of the pushrod which acts as a little buffer between the slave cylinder and servo. During a PO’s tenure, the assembly must have been lost which explains why the last rubber seal appeared to have been glued into the servo-end of the slave cylinder. As this part doesn’t come with the servo repair kit, I’ve made a hard plastic replacement whilst I source a similar sized bearing.

The unit has now been reassembled and fitted for the fifth time and it seems to be holding brake pedal pressure. Perhaps the Youngtimers Show at Gawsworth Hall is still a possibility tomorrow...

Adrian