Brakes Jammed On.

[Ramsden]

This weekend I experienced a problem with the brakes (not handbrake) of my Plus2. This involved the brakes coming on without my operating the foot pedal. The problem occurred after about fifteen minutes of starting the car from cold and having driven down a fairly straight A-road at between 50 and 60mph, involving little use of the brakes.

The first indication of a problem was that the car would not accellerate easily, I decided to pull over and in doing so noticed that the brake pedal had become incredibly hard with minimal/no travel.

On stopping I noticed that there was smoke coming from the front calipers. After five minutes standing, and several pumps of the brake pedal, pedal feel returned to normal, the wheels turned freely and the brakes functioned as before. I was able to make it home at a steady slow pace.

My instinct is to suspect the servo, a single replacelement Lockheed item activating both brake circuits. However, I am something of a newcomer to the world of car maintenance. Any suggestions and recommended remedies would be welcome.

The car was last serviced six months ago.

Cheers

Simon
'73 Plus 2 130/5

[theelanman]

Simon
my plus 2 (1967) did the same...it was with the original girling servo.....
I put up with the intermittant clamping on as I couldnt find the problem until the seals of the servo collapsed as I came upon a roundabout at the end of a bypass....
trying to stop from 80mph with no brakes is somewhat frightening.......I would therefore suggest that you either rebuild the servo........or buy one that has been reconditioned ......or replace it with a lockheed servo unit.....I personally went for the lockheed replacement as they can still be sourced as can the bits....where as the girling unit is obsolete and the new set of seals/O ring are very hard to source.........
the smell of fear is not good so I suggest acting sooner rather than late unless you plan on keeping the top speed to about 5mph
the recon girling unit is also more expensive than the lockheed servo.....I payed ?200 fitted for mine in August (lockheed fitted) where as the recon girling unit was ?193 +vat.......
there are a couple of good places if you need contact info give me a shout
cheers
Gareth
(1967 +2)

[Dave_Newcastle]

Had similar problem which I traced to the lockheed servo. In my case it was the small piston sticking on the air side of the servo (located under the white cap). A temporary cure was found by removing cap (appro six screws)and removing the membrane under. Then dropping in small amount of brake fluid and special brake seal grease to lubricate bore. Reassembled and it worked a treat. Previously brakes tended to stick on momentarily when pedal released and this all but cured that symptom.

Following advise from lockheed help desk who told me that this was common reported fault with lockheed servo on plus 2, I remounted servo in different orientation as per their advice. Previously the servo had been mounted with air valve (white cap) at top - ie 12 o clock position. They advised that it should be mounted at either 4 or 8 o clock position. Also ensure that the outlet of servo is slightly higher than inlet to aid bleeding. Did this and no problems since (five years later).

Hope above helps

Dave

[berni29]

I had the same thing happen in my plus 2 as well, except I was at the head of a queue of traffic at some lights. The brakes locked on and that was it. I could not move the car. Everyone behind thought that I was being bloody minded about leaving the car and not pushing it to the side of the road. It was a nightmare. When the recovery people turned up the engineer went straight round to the offside front caliper and opened the bleed valve a little. That released the pressure and got the car going again. From then on I carried a bleed spanner with me in the car. I cleaned the little filter on the servo and that seemed to cure it.

[dgym]

Just thought I'd come and add a plus one for the re-mounting of the Servo as after having read this post, I flipped my servo and it appears to have cured my brake sticking problem.

mounting instructions: http://gentry.zxq.net/Remote_Servo_Installation.pdf

cheers,
Jim