Bosch Hydromax brake booster info

[CarolinaHD]

For my 1967 c50 292, I added power steering with brackets from ebay, I'm using all factory drums on the 4 corners, new nickel copper brake lines, new dorman rubber brake lines, relined shoes and utilizing 2 of the factory brass brake blocks for the new split system master cylinder. I opted not to use a proportioning valve because it's all drums. You will need some 10lb residual pressure valves for each line. Google for more info about this.

I ordered a brand new complete Hydromax unit for $450 off ebay and it bolted right in. This particular part number didnt bring up much info but I believe it's from a freightliner. I also bought a Delco hy-power style booster from a mid 80s c50 and it bolted right in as well. The main difference between the two is the hy-power booster has 1 high pressure inlet and 2 outlets, high pressure and low. This is similar to the smaller trucks hydroboost where the fluid flows down to the steering box from the booster. The Hydromax system has 1 inlet and 1 low pressure outlet. This is ideal for my truck because it doesn't have power steering.

The inlet size is 1/2" oring tube and I could not find that fitting anywhere. I had to find the factory high pressure line for a 2007 c5500 and have a hydraulic shop cut off the other end for the factory power steering pump. The pump outlet is 3/8" so the shop crimped a 1/2" fitting on the hose and used a 1/2"-3/8" compression adapter with the factory tube.

My plan for hooking up the backup pump is to retrofit the harness from a kodiak/topkick or just wire it to a relay and momentary push button incase of ps pump failure.

I plan on plumbing my residual valves in between the copper and rubber lines right below the master cylinder.

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