User guide

Section I - Trouble Shooting & Guidelines • Page 7
TROUBLE SHOOTING THE HYDRO-BOOST - Part 1
HYDRO-BOOST BRAKE BOOSTERS
PROCEDURE FOR NOISE - SLOW OR INCOMPLETE BRAKE PEDAL
RETURN - OVERSENSITIVE BRAKING - SELF-APPLYING BRAKES
NOISY BRAKE BOOSTER
VERIFY COMPLAINT
1. TYPE OF NOISE.
2. WHEN IT OCCURS.
IF THE NOISE OCCURS
DURING:
• HIGH BRAKE PEDAL
EFFORTS.
• QUICK PEDAL RELEASE.
SEE NORMAL OPERATION
NOISES AND COMPARE WITH
A KNOWN ACCEPTABLE SYS-
TEM.
HYDRO-BOOST BRAKE
NOISE CHARACTERISTICS:
NORMAL OPERATING
NOISES
NORMAL HYDRO-BOOST
BRAKE UNITS WILL PODUCE
CERTAIN CHARACTERISTIC
BOOSTER NOISES. THESE
NOISES OCCUR, FOR THE
MOST PART, WHEN THE BRAKE
PEDAL IS MANIPULATED IN A
MANNER NOT ASSOCIATED
WITH EVERYDAY BRAKING OR
DRIVING HABITS. THE GEN-
ERAL CATEGORIES OF NOR-
MAL OPERATING NOISES ARE:
(1) HISSING NOISES AND (2)
CLUNK CLICK/CHATTER
NOISES.
IF THE NOISE
OCCURS DURING:
• LOW BRAKE
PEDAL EFFORT.
• ENGINE IDLE -
NO PEDAL
EFFORT.
• NORMAL DRIVING
CONDITIONS.
OPERATE THE VE-
HICLE UNTIL THE EN-
GINE IS AT NORMAL
OPERATING TEM-
PERATURE.
DUPLICATE THE OP-
ERATING CONDI-
TION ABOVE AND
LISTEN FOR NOISE.
COMPARE RESULTS
WITH A KNOWN AC-
CEPTABLE SYSTEM.
ERRATIC OPERATION,
STICKS, BINDS OR GRABS.
RUN PUMP AT FAST IDLE.
PULL THE BRAKE PEDAL
REARWARD WITH APPROXI-
MATELY 10 POUNDS FORCE.
RELEASE THE PEDAL AND
MEASURE THE DISTANCE
TO THE FLOOR BOARD.
MAKE A 100 POUND BRAKE
APPLICATION. RELEASE THE
BRAKE PEDAL AND AGAIN
MEASURE THE PEDAL TO
FLOOR BOARD DISTANCE.
THE PEDAL SHOULD RE-
TURN TO ITS ORIGINAL PO-
SITION.
IF THE PEDAL DOES NOT RE-
TURN PROPERLY, CHECK
THE PEDAL TO BE SURE IT IS
OPERATING FREELY. COR-
RECT ANY STICKING, BINDING
AS NECESSARY.
IF PEDAL IS FREE - CHECK
FOR OBSTRUCTION IN THE
RETURN LINE AND CONNEC-
TIONS BETWEEN HYDRO-
BOOST AND PUMP RESER-
VOIR.
REMOVE OBSTRUCTION OR REPLACE LINE AS RE-
QUIRED. IF CONDITION REMAINS, CHECK FOR A
DAMAGED REACTION END. IF DAMAGED, HYDRO-
BOOST SHOULD BE REPLACED OR REPAIRED.
IF THE PEDAL IS
FREE OF ANY
BINDING CONDI-
TION, AND THERE
ARE NO OB-
STRUCTIONS IN
THE RETURN
LINE, REMOVE
THE MASTER CYL-
INDER RESER-
VOIR COVER.
OBSERVE THE
BRAKE FLUID IN
THE RESERVOIR
WHILE RAPIDLY
DEPRESSING THE
BRAKE PEDAL
ONE INCH.
FLUID SURFACE
SHOULD HAVE
SOME MOVEMENT
OR SPOUT IN THE
FORWARD RESER-
VOIR SECTION. MI-
NOR SPOUTING
MAY OCCUR IN THE
REAR RESERVOIR
SECTION ALSO. IF
NO MOVEMENT OR
SPOUTING OR
FLUID OCCURS IN
FORWARD RESER-
VOIR SECTION,
THE HYDRO-
BOOST UNIT IS DE-
FECTIVE AND
MUST BE RE-
PLACED OR RE-
PAIRED.
IF HYDRO-BOOST WILL EMIT NORMAL HISSING NOISES WHEN ABOVE NORMAL BRAKE PEDAL EFFORTS ARE
APPLIED (40 LBS. PEDAL EFFORT AND UP). THE HISS SOUNDS ARE PARTICULARLY NOTICEABLE WITH THE
VEHICLE MOTIONLESS AND WILL INCREASE IN INTENSITY AS PEDAL PRESSURE INCREASES ABOVE 40 LBS.
AND SYSTEM OPERATING TEMPERATURE INCREASES. LOUD HISSING SOUNDS AT OR BELOW NORMAL (20-
25 LBS.) PEDAL EFFORT WARRANTS INVESTIGATION.
CLUNK, CHATTER OR CLICKING NOISES WILL BE HEARD WHEN THE BRAKE PEDAL IS QUICKLY RELEASED
FROM HARD (50-100 LBS.) PEDAL EFFORTS.
SECTION I - TROUBLE SHOOTING & GUIDELINES