Brake issues 82 f700
Thread Starter
|
New User
Joined: May 2020
Posts: 1
Likes: 0
Brake issues 82 f700
Hey guys I am new to the site. I just got an 82 f700 with 370v8. I have brakes but not until the pedal reaches the floor. Then the kinda lock. I don’t have the hydrovac system. I have an electric motor on the back of the master cylinder. Attached to what I assume is a power booster. My parking brake is a standard push with foot pedal on the far left. So not the Lucas system. The electric brake motor light is on on my dash. Solid no blinking. Just like the pedal has no pressure then all of a sudden the brake engages at the bottom of the pedal. Help if you can please.
Fleet Mechanic
Joined: Feb 2007
Posts: 1,652
Likes: 79
From: Mooresville, NC
OP - your system is a Hydro-Max Power Brake Booster that uses a 50/50 split hydraulic, newer systems (1984 on) use a 60/40 split so you have to source the right parts, DO NOT INTERCHANGE. Basically, with the light illuminated on the dash it's saying the RESERVE SYSTEM, controlled by the electric pump motor assembly below the master cyl/Hydro Max Booster Assembly, is INOPERATIVE and won't be there when you need it -- do not drive this vehicle. The reserve system detects when normal hydraulic flow is interrupted and that electric motor kicks in providing power for stops. Areas to check:
(1) Orings -- there are two sealing orings @ pump --- they fail frequently and should be replaced with higher quality orings
(2) Electrical -- electric pump motor relay and pump operation, wiring
(3) Air in system -- bleeding
(4) Malfunctioning check valve in Hydro Booster Assembly
Here's a fast way to do a basic checkout:
With engine off, depress the brake pedal. The electric motor SHOULD RUN, amber light on dash should illuminate and the warning buzzer should sound.
Start the engine, push the brake pedal several times. There should be no warning signals and the electric motor SHOULD NOT RUN.
(1) Orings -- there are two sealing orings @ pump --- they fail frequently and should be replaced with higher quality orings
(2) Electrical -- electric pump motor relay and pump operation, wiring
(3) Air in system -- bleeding
(4) Malfunctioning check valve in Hydro Booster Assembly
Here's a fast way to do a basic checkout:
With engine off, depress the brake pedal. The electric motor SHOULD RUN, amber light on dash should illuminate and the warning buzzer should sound.
Start the engine, push the brake pedal several times. There should be no warning signals and the electric motor SHOULD NOT RUN.
Thread
Thread Starter
Forum
Replies
Last Post
captain2207
1987 - 1996 F150 & Larger F-Series Trucks
2
Sep 20, 2013 06:49 AM
baby2000
1999 - 2003 7.3L Power Stroke Diesel
16
May 26, 2009 04:19 PM
