Parisienne V8-307 5.0L (1986)
Brake Proportioning/Combination Valve: All Technical Service Bulletins
Brakes, Brass Combination Valve - Extended Pedal Travel
Number 86-5-19B
Date 11/88
Subject:
INCREASED PEDAL TRAVEL - POWERMASTER
1986 PARISIENNE WAGON (BLEED SYSTEM, REPLACE COMBINATION VALVE)
"This bulletin supersedes bulletin 86-5-19A, dated 9/87. This bulletin has been revised to specify "brass" valve for P/N 25509419 and clarify this brass
valve is the only type now available; added a sentence under "Diagnosis of Condition" regarding cast iron combination valves."
DIAGNOSIS OF CONDITION:
Some 1986 Parisienne wagons may experience increased pedal travel at higher mileage/extended use. This may be the result of air ingestion at the
combination valve and traveling to the left front caliper.
In order to diagnose this condition, bleed the left front brake assembly. If this results in less pedal travel, the combination valve should be replaced with
brass valve Part Number 25509419 to prevent reoccurrence of the condition (this brass valve is the only type now available from GMSPO). The entire
brake system should be re-bled, and master cylinder fittings checked for proper torque. If the pedal travel is still long and no air is found after the initial
bleed, refer to the Service Manual for the servicing procedure.
Any cast iron combination valve in dealer stock may be used on other applications.
ADDITIONAL SERVICE INFORMATION:
Some dealers are still replacing the whole Powermaster unit instead of using the appropriate service kits available for the Powermaster assembly. Proper
diagnosis per the Service Manual will indicate the correct kit to use.
The following repair kits have been released to assist in servicing the Powermaster brake units. The labor times indicated include time for the functional
system check and diagnostic procedure.
PART
LABOR OP.
LABOR TIME
NUMBER
DESCRIPTION
NUMBER
NUMBER
18011279
Pump and Motor Asm. Package
H0980
.8
18014977
Pressure Switch Asm.Package
H0778
.4
18014978
Accumulator Asm. Package
H0985
.3
18013293
Reservoir Cover Asm. Package
H0610
.2
18011398
Boot Package
T1377
.4
18010875
Bracket Package
T1378
1.1
18011403
Sump Hose Package
H0745
.3
Parts are currently available from GMSPO.
