Flavia Hydrovac brake servo required

[phil-m]

Does anyone have an old Flavia remote servo for sale, the remote Hydrovac type. Mine has developed a bit of a habit for brake fluid so I would like to rebuild another and then swap them over. Any advice on rebuilding would also be greatfuly accepted.

[lancialulu]

Consortium sell an after-market replacement and Omicron renovate if that helps. It is a weird system - I have just got a Flavia Vig and am going through it before the MOT. I bled the brakes in the normal way without realising you should first start at the slave cylinder. Anyway seemed to be OK and changed the fluid and got the air out.....

[ColinMarr]

Phil,

I missed this question when you first raised it – sorry. The remote servo fitted to Flavia and Flaminia earned a poor reputation for unreliability, but in my experience a lot of this was unfounded. I successfully rebuilt the servo for my car in the mid 1980s and went on to do two more for others. The system is only marginally more complicated than the dual circuit master-cylinders fitted to Flavia and Fulvia – it you are OK with that then doing the servo should be no more problematic.

The most common fault was brake fluid getting past the seals at the vacuum chamber end of the unit, into the chamber and then into the inlet tract with lots of white smoke in the exhaust to prove it!

One of the problems then was the lack of seals. Rebuild kits were not available in the UK and at least two of the cup seals seemed to be almost unique to this system. I searched through the parts bins of a motor factor that was supposedly a Lockheed agent and I found cup seals that did the job, others were simple ‘o’ rings that were easy to obtain.

Another problem was that the design of this system involved a side-shoot from the main cylinder going off at an angle (and hence blind) to the air filter, so that it was impossible to push the piston out with a wooden dowel. The trick (leaned from the wizard Tony Amato) was to tap the flange end of the side-tube with a pin-hammer until low-and-behold the piston with its ‘o’ ring rises up out of the housing until you can grip it to pull it out. Any slight damage to the flange needs to be flattened out.

Cleaning up the bores with very fine abrasive paper, fitting new seals and putting it all back together seemed to complete the job.

Of course, you may now find an alternative remote unit off the shelf, but when I did it that wasn't an option.

Good luck!

Colin