Syclone V6-262 4.3L Turbo (1991)
2.
Ensure that the master cylinder is full.
3.
Install two bleed valve tools on the 4WAL EHCU at the high pressure accumulators (HPA).
4.
Install one bleed valve tool on the combination valve. DO NOT OVER TIGHTEN THE WING NUT. Doing so will result in brake fluid leaking
from the combination valve.
5.
Back off the two internal bleed screws on each side of the EHCU 1/4 to 1/2 turn.
6.
Use a conventional bleeding process (pressure, vacuum or manual).
7.
Bleed the 4WAL modulator before bleeding the wheel cylinders.
8.
Open the bleed valves at the front of the modulator one at a time for approximately 10 seconds. DO NOT OVER TIGHTEN.
9.
Always maintain a full master cylinder.
10.
Bleed the right and left rear wheel cylinders.
11.
Bleed the right front and left front wheel cylinders.
12.
Remove the bleed valve depressors and tighten the side internal bleed screws. DO NOT OVER TIGHTEN.
13.
Evaluate the brake pedal feel. If firm, continue with this procedure. If the pedal is soft or spongy, reinstall tools and rebleed the system, starting
with step 1.
14.
Perform 3 function tests using the manual test or the Tech 1 function test procedure.
15.
Road test the vehicle, applying the brakes several times.
Without ABS System
Manual Bleeding
1.
If vehicle is equipped with power brakes, remove vacuum reserve by applying brakes several times with engine off.
2.
Fill master cylinder reservoirs with suitable brake fluid. Be sure to always keep master cylinder reservoirs at least half full during entire
bleeding procedure.
3.
If master cylinder is suspected to have air in the bore, it must be bled first, as follows:
a.
Disconnect forward brake pipe connection at master cylinder.
b.
Allow brake fluid to fill master cylinder bore until it begins to flow from forward pipe connector port.
c.
Connect and tighten forward brake pipe at master cylinder.
d.
Depress brake pedal slowly one time and hold, then loosen forward brake pipe connection at master cylinder to purge air from bore. Tighten
connection, then release brake pedal slowly. Wait 15 seconds, then repeat sequence, including 15 second wait, until all air is purged from
bore.
e.
Bleed rear bore of master cylinder as front bore was bled.
4.
Bleed right rear brake as follows:
a.
Depress brake pedal slowly one time and hold.
b.
Loosen bleeder valve to purge air from brake, then tighten bleeder valve and slowly release pedal.
c.
Wait 15 seconds, then repeat sequence, including 15 second wait, until all air is purged.
5.
Bleed left rear, right front, and left front brakes, in that order, using same method as for right rear brake.
6.
Check brake operation and ensure pedal is firm. Also check master cylinder fluid level and add fluid as necessary.
7.
Turn off brake warning light by applying moderate pressure to brake pedal several times.
8.
Road test vehicle.
