aux. power brake booster 66 w100

moparverb · Post by **moparverb** » Thu Jan 11, 2007 7:18 am

here is a question for all. my 66 w100 has single cyl. brake master on the fire wall then under the cab it has a vac booster with another single master that has a 4 way tee to connect left front right front and both rears. i bypassed the whole thing for now and just coupled the master to the fronts just to move around, my main question is has anyone rebuilt this type of system? or i was thinking about going with a duel cyl master and proporting valve to the drum brakes like i did on my 66 d100. thanks jason

Post by **Hobcobble** » Thu Jan 11, 2007 8:22 am

I haven't messed with that type of booster on your
W but I did convert my '61 D200 to a dual reservoir
master cylinder. I used a junction block from a '71
W200.
John

Website · Post by **wideblock** » Thu Jan 11, 2007 7:51 pm

man did you ask the right question at the right time. i just spent a week doing all this to my 65 crew cab. what you have is known as the hydro vac system. i never found anyone who could rebuild them, but i didnt look real hard either. if you want to just go to manual brakes. take the line from the master to the port on the splitter block that the hydrovac plugs into. its that simple. youll have to make a new line. but its not that big a deal. then remove the hydro unit. now, if your gonna convert to a diual master, it aint hard, but, no wait, BUT, youll have to rerun all the lines to make it fit right. see the factory dual line systems had the power booster on the fire wall, so the splitter block was on the frame just under the master cylinder. your splitter is under the drivers seat. about 2-3ft from where it needs to be to make the swap easy. personally, i would go with the 67 dual res cylinder and a 67 power booster. they are both still available thru car quest and napa. then re run the hard lines. youll wind up with a much safer truck by doing this. if you stay single res cylinder, then just by pass the hydrovac with a single new hard line. or you can do like i did and just use a coupler to join the line to and from the hydrovac, thus by passing it. but that was temporary, so the ugly coupling didnt bother me.