Off Road Unlimited 63500-D Chevy/GMC Hydro-boost Upgrade Kit for 88-93 Trucks, Suburbans, and Blazers - Manual (Page 2)

ORU - Hydro-Boost Kit ‘88-’93 GM 1500-2500 Suburbans and Blazers
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page 1
INSTALLATION NOTES:
• Inspect the contents of the kit and read the entire instructions before proceeding.
• We recommend this installation be performed by a qualified technician.
• Torque all hardware to factory specifications.
• We recommend using red Loctite on all bolts.
• When removing wheels, support vehicle with jack stands.
1) Disconnect the battery.
2) Disconnect the brake pedal rod retaining clip and washer carefully.
3) Disconnect the brake lines from the master cylinder, then remove the master cylinder.
4) Remove the 4 vacuum brake booster to firewall attachment nuts, then carefully remove the
brake booster from vehicle (you may have to gently pry the unit loose of the firewall).
5) Assemble the brake pedal rod adapter onto the hydraulic brake assist unit threaded pedal
rod, applying a small amount of grease to the brake pedal rod eyelet.
6) Install the hydraulic brake booster carefully to the firewall, with the hydraulic fittings facing
downward, the accumulator bottle to the driver’s side, while aligning the brake pedal rod to
brake pedal interface as required.
7) Using the 4 replacement nuts, securely fasten the hydraulic assist unit to the firewall.
8) Bench bleed the replacement master cylinders thoroughly, then install securely onto the
hydraulic brake assist unit (’96 – ’99 C/K2500 “hydro boost spec” MC recommended).
9) NOTE: Since you have not introduced any large amounts of air into the brake lines during these
procedures, it IS possible to connect the brake lines to the replacement master cylinder (leaving
the fittings a bit loose initially), allowing gravity to bleed the remaining air out of the lines at
these connection points. After the fluid begins to drip out of these line connections, tighten up
the lines. (Tip: have a towel handy to catch the fluid)
10) Adjust the brake pedal height setting by spinning the threaded pedal rod in or out of the
adaptor as desired.
11) Double check for appropriate thread engagement at pedal rod adaptor, (10-thread minimum)
and then tighten the brake pedal rod jam nut firmly. (Do not over torque!)
12) Connect the pedal rod to the brake pedal, install the retaining clip and washer securely.
13) Remove the existing p/s high side power steering line, allowing the system to drain.