Brake locking master cylinder issues

25th March 2012

I had been becoming more aware that it was not so much my engine carburetion problems that was preventing my buggy running correctly , but the brakes being applied whilst driving without the pedal being depressed. This was more noticeable whilst traveling up hills as the buggy would slowly come to rest with all four wheels locked. I could tell this was a hydraulic issue as If I bled the rear brakes. The brakes seemed to release and the buggy would roll again for a bout 5 miles before the problem repeated.

I decided that I would have to take the plunge and purchase a new master cylinder even though my previous master cylinder had seen little wear. GSF sell to different quality replacements and I went for the German. I decided to paint the Master Cylinder before fitting . I painted it with red oxide primer and Hammerite Hammered finish black paint. I left the bungs in place whilst I painted to ensure that the paint could not ingress into the internal parts.

The front wheel was removed to allow access to the M/C . The three brake lines was then undone with an 11mm spanner. Oddly no fluid came out of the MC before I put in the the bungs. I then undid the two 13mm bolts in the drivers side bulkhead and allowed the M/C to be removed. The general outside condition of the unit was fair. I drained off the brake fluid from the reservoir to a Jam Jar that could be taken and dispersed of properly. I removed the reservoir from the M/C as it is just a press fit and cleaned it thoroughly. The Brake fluid that came off the car seemed noticeably stiff. I took the rubber washers out of the old M/C and reassembled them into the new M/C. The Volvo reservoir was just pushed back into the grommets till it was seated.

The refitting process was pretty straight forward. I removed the M/C rubber hood and thoroughly greased the inside before replacing the cover. This whole unit was then passed through the bulkhead onto the activation shaft. Once in place it was propped in place and bolted through the bulkhead. The brake lines was then attached and the whole brake system was bled with a one man bleed kit.