AD-IPAIR DRYER TROUBLESHOOTING CHART (Continued)

SYMPTOMS

CAUSE

REMEDY

1. Dryer is constantly

 

1. Test fittings, hoses, lines and connections.

 

Apply soap solution to detect excessive

“cycling” or purging.

 

 

leakage. Tighten or replace as needed then

Dryer purges frequently

 

 

repeat the air dryer charge-purge cycle and

(every 4 minutes or less

 

 

observe the gauge installed in the supply

while vehicle is idling)

 

 

reservoir. If leakage is within limits remove gauge

(continued).

 

 

from reservoir and replace drain cock or valve. If

 

 

excessive leakage is detected, continue testing.

 

 

2. Test accessories connected to supply reservoir.

 

 

Drain all air pressure from system, disconnect

 

 

all air lines leading to accessories (fan clutch,

 

 

wipers, air seats, etc.) and plug the reservoir at

 

 

disconnection point. Build air system pressure

 

 

until air dryer purges and observe supply

 

 

reservoir gauge. If leakage is no longer

 

 

excessive, repair or replace leaking accessory. If

 

 

excessive leakage is detected, continue testing.

 

 

3. Test governor leakage. Build system pressure to

 

 

governor cut-out, turn off engine and apply soap

 

 

solution to governor exhaust port and around

 

 

cap. Leakage should not exceed a 1 in. bubble

 

 

in 5 seconds. Reduce system pressure to 80 psi

 

 

or less, and re-apply soap solution. Leakage

 

 

should not exceed a 1 in. bubble in 5 seconds. If

 

 

excessive leakage is detected in either test,

 

 

repair or replace governor.

 

 

4. Test compressor unloader leakage. Drain all air

 

 

pressure from system and remove the governor

 

 

from the compressor. Temporarily plug the

 

 

governor unloader port or air line that mated with,

 

 

or connected to, the compressor. Build air

 

 

system pressure until air dryer purges then

 

 

IMMEDIATELY SHUT OFF THE ENGINE.

 

 

Observe the air gauge in the supply reservoir. If

 

 

leakage is within limits, replace the compressor

 

 

unloaders. Re-connect the governor to the

 

 

compressor (after removing plug installed in

 

 

governor) and retest while observing supply

 

 

reservoir gauge. If excessive leakage is

 

 

detected, continue testing.

 

 

5. Test air dryer purge valve and outlet (delivery)

 

 

check valve. Drain all air pressure from system,

 

 

remove the control line connection at the air

 

 

dryer and plug the end of the air line leading to

 

 

the governor (not the air dryer control port). Build

 

 

system pressure to governor cut-out and observe

 

 

air gauge. If little or no pressure drop is observed

 

 

replace the air dryer check valve. If pressure

 

 

drop continues, apply soap solution to air dryer

 

 

purge exhaust and purge control port (where the

 

 

control line was removed). Leakage should not

 

 

exceed a 1 in. bubble in 5 seconds. If leakage is

 

 

excessive repair or replace purge valve

 

 

assembly.

 

 

 

 

 

17

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BENDIX AD-IP INTEGRAL PURGE AIR DRYER manual AD-IPAIR Dryer Troubleshooting Chart