Antony
G-Wagen Club SA
A little while ago I noticed that my brakes were feeling quite hard and there was a hissing sound of air escaping in the driver foot well. I tested the vacuum system with a kit I bought at Adendorffs and sure enough, the system pumped up to the correct vacuum, and held it unless I pressed the brake, then it lost all vacuum so I suspected my brake booster had developed a leak, not great news as the ones we have in the G are not serviceable and they are expensive to replace.
I took the car to Summit Brake in Rivonia Rd, where they were kind enough to quickly test it and confirm my diagnosis. The hunt began for a second-hand booster. There are tons of them lying at CJ Autospares in Edenvale, but only one or two with the correct four bolt firewall configuration. Eventually I bought one off one of our members here, who was kind enough to sell it to me. It was from a LHD G and the fork that attaches to the brake pedal needed to be shortened by about 27mm. Summit Brake was kind enough to do that and test it for me all for 1 hour's labour charge. I fitted it myself, there's only six nuts to tighten, four on the firewall and two on the master cylinder which you need to remove to get the booster out, but you don't have to open the brake circuits, so no bleeding required. That is what the coils in the brake lines under the master cylinder are for.
In my research I saw that a W140 S500's brake booster will also fit, the R107 450 SLC fits too but thats even older than our Gs and if you find one, its likely already broken
I took the car to Summit Brake in Rivonia Rd, where they were kind enough to quickly test it and confirm my diagnosis. The hunt began for a second-hand booster. There are tons of them lying at CJ Autospares in Edenvale, but only one or two with the correct four bolt firewall configuration. Eventually I bought one off one of our members here, who was kind enough to sell it to me. It was from a LHD G and the fork that attaches to the brake pedal needed to be shortened by about 27mm. Summit Brake was kind enough to do that and test it for me all for 1 hour's labour charge. I fitted it myself, there's only six nuts to tighten, four on the firewall and two on the master cylinder which you need to remove to get the booster out, but you don't have to open the brake circuits, so no bleeding required. That is what the coils in the brake lines under the master cylinder are for.
In my research I saw that a W140 S500's brake booster will also fit, the R107 450 SLC fits too but thats even older than our Gs and if you find one, its likely already broken
