BENDIX SD-08-2412 manual Low Air Use, High Air Use

Table A: Maintenance Schedule and Usage Guidelines

Regularly scheduled maintenance is the single most important factor in maintaining the air brake charging system.

Vehicle Used for:	Axles
	No. of
Low Air Use
Compressor with less than 15% duty cycle
e.g. Line haul single trailer	5
	or
w/o air suspension, air over
	less
hydraulic brakes.
Compressor with up to 25% duty cycle
e.g. Line haul single trailer	5
with air suspension, RV,	or
school bus.	less
High Air Use
Compressor with up to 25% duty cycle
e.g. Double/triple trailer,
open highway coach, (most)
pick-up & delivery, yard or
terminal jockey, off-highway,	8
construction, loggers, concrete
	or
mixer, dump truck, fire truck.
	less

Compressor with up to 25% duty cycle
e.g. City transit bus, refuse,
bulk unloaders, low boys,
urban region coach, central tire	12
inflation.
	or
	less

Column 1	Column 2		Column 3	Column 4	Column 5
Typical	Discharge		Recom-	Recom-	Acceptable
			mended	mended	Reservoir
Compressors		Line	Air Dryer	Reservoir	Oil Contents3
Spec'd			Cartridge	Drain	at Regular
	I.D.	Length	Replacement1	Schedule2	Drain Interval

				1/2 in.	6 ft.			Bendix®
								BASIC™ test
			compressor	For oil carry-over			Recom-	acceptable
				control4 suggested				range:
				upgrades:			mended	3 oil units
				5/8 in.	9 ft.
						Every 3	Every	per month.
							Month -	See
						Years
			air
				1/2 in.	9 ft.		Max of	appendix
	921® air compressor		Bendix® Tu-Flo®550
				For oil carry-over			every 90	A.
							days
				control4 suggested
				upgrades:
				5/8 in.	12 ft.			For the
								BASIC
								Test Kit:
								Order
	-
	BA							Bendix
								P/N
	Bendix®
compressor								5013711
				1/2 in.	12 ft.
				For oil carry-over		Every 2
						Years
air				control4 suggested
				upgrades:
Tu-Flo®750
			compressor	5/8 in.	15 ft.			BASIC™ test
								acceptable
								range:
							Every	5 oil units
Bendix®			air					per month.
							Month
			™					See
		596
								appendix
			DuraFlo	5/8 in.	12 ft.
								A.
						Every
			or	For oil carry-over
						Year
		®,
				control4 suggested
		922		upgrades:
			BA-	3/4 in.	15 ft.
			Bendix®

Footnotes:

1With increased air demand the air dryer cartridge needs to be replaced more often.

2Use the drain valves to slowly drain all reservoirs to zero psi.

3Allow the oil/water mixture to fully settle before measuring oil quantity.

4To counter above normal temperatures at the air dryer inlet, (and resultant oil-vapor passing upstream in the air system) replace the discharge line with one of a larger diameter and/ or longer length. This helps reduce the air's temperature. If sufficient cooling occurs, the oil-vapor condenses and can be removed by the air dryer. Discharge line upgrades are not covered under warranty. Note: To help prevent discharge line freeze-ups, shorter discharge line lengths or insulation may be required in cold climates. (See Bendix Bulletins TCH-008-021 and TCH-008-022, included in Appendix B, for more information.)

5For certain vehicles/applications, where turbo-charged inlet air is used, a smaller size compressor may be permissible.

Note: Compressor and/or air dryer upgrades are recommended in cases where duty cycle is greater than the normal range (for the examples above).

For Bendix® Tu-Flo®550 and 750 compressors, unloader service is recommended every 250,000 miles.

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