Installing Hydroboost brakes

[papajeep]

Okay. It’s been a while since I indicated my desire to add hydroboost brakes to my 1981 CJ8; but that is because I ran into some problems in the process. My mechanic, and my son both encouraged me to get rid of the manual brakes and switch to hydroboost. They both recommended them over vacuum assist brakes as being stronger.

Hydroboost brake systems use the power steering pump and fluid to exert a hydraulic like system to increase the pressure to the brakes.

So, I scoured the web and found a hydroboost unit from a salvage lot in the South. Sorry, but I don’t remember the exact location or the name of the supplier. The unit was off a ’97 Dodge Ram 2500 diesel. I would strongly suggest you get the hydroboost unit complete with master cylinder and reservoir and the hose kit for an easier install. I listened to my son who said it would be cheaper to get it piece meal; but it was aggravating to me. I purchased the unit; then the master cylinder, then the hoses in three separate purchases, but I would not try that again.

NOTE: My unit was off a ’97 Dodge, as I stated, and the brake lines bolted directly into the Dodge master cylinder and the hoses screwed directly into the power steering unit and into the steering box. My son used a newer unit and needed to get adapters to fir the master cylinder as Dodge went to metric sometime in the 2000’s.

 

[papajeep]

The procedure:
Remove the old manual unit.

[FONT=&quot]Align the new unit against the firewall with the hydroboost reservoir to the top. Measure the distance to your brake pedal and mark new holes for the unit. (It helps to have another person help you with this.) I needed to cut out about 2” (if I remember correctly) of the plunge rod and weld the ring end back onto the unit.

[/FONT] [FONT=&quot]The plunge rod; cut, re-welded, and installed.[/FONT]
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[papajeep]

Be sure the plunge rod is long enough to keep the pedal extended.
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[papajeep]

Drill the holes in the firewall and mount the Hydroboost unit.

I needed to place an adapter block between the hydroboost and the master cylinder as the unit had mounting holes at 30 degrees and the master cylinder has holes horizontal. (Again, get a COMPLETE unit so you have everything you need)

Attach the master cylinder and reservoir.

[FONT=&quot]Attach the brake lines.[/FONT]

 

[papajeep]

[FONT=&quot]I needed to place an adapter block between the hydroboost and the master cylinder [/FONT]

 

[papajeep]

Attach the hoses. (A power line from p.s. pump to hydro unit; power line from hydro unit to steering box; return line from steering box and hydro unit (tee them together) to the p.s. pump) I used my stock p.s. pump and steering box from my old AMC 360.

 

[papajeep]

The biggest hangup in my install was the reservoir. I got my unit all together and tried to shut the hood, but the reservoir was too tall. I cut a ¾” piece out of it and glue the two pieces together to make it shorter. All three times that I epoxied, super-glued, etc the plastic together, the brake fluid dissolved the glue. So, again to the internet I went to find a smaller (in height) reservoir. My choice was a PBR Brake Master Cylinder (part # W0133-1621626; Available from Auto Parts Deal or Auto Parts Warehouse).

 

[papajeep]

New PBR reservoir installed. The hood now closes.

 

[papajeep]

Fill the power steering pump with fluid.

Fill the reservoir with brake fluid and bleed the brakes.

Be careful the first time you apply the brakes! They are strong! I have a soft pedal feel, but I need not press very hard for the brakes to hold. No more cramping at long red lights, or shifting to neutral to ease the pressure of manual brakes.

ONE PRECAUTION: If you are wheelin’ and the engine shuts off; you have about three pushes on the pedal until you no longer have brakes. The reservoir on the hydroboost unit is to help in this situation, but you would be best to keep you Jeep running.


This is a pic of the final installation: