BENDIX BW1811 manual AD-IPAIR Dryer Troubleshooting Chart

AD-IP™AIR 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.

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