Bendix Oil Coalescing Air Treatment Solutions
Protect Your Investment Trust the Best. Trust Bendix.
With EPA 07 and EPA 10, the pressure is on you to protect your investment in new vehicle technologies. When air contaminated with oil is sent into these systems, you risk considerably shortening its life and possibly spending a great deal to repair it. Choose PuraGuard oil coalescing air dryers by Bendix Commercial Vehicle Systems. Theyre the best in the business, with competitive test data to prove it.

1000 900

We say Bendix makes the best air dryers. You say, prove it.
The competitive test data, shown in part on the chart, demonstrates the superior oil coalescing performance of Bendix air dryers. According to the data, Bendix PuraGuard oil coalescing equipped air dryers outperform WABCO oil coalescing equipped air dryer cartridges in head-to-head comparisons. Bendix unequivocally removes more oil. Based on the data, the Bendix ADIS air dryer with oil coalescing is over 200 times more effective at removing oil than the WABCO SS1200P air dryer with Air System Protector oil coalescing.
Further Test Data Highlights
The Bendix AD-IP air dryer with PuraGuard oil coalescing is over 30 times better than the WABCO SS1200P with Air System Protector oil coalescing
(For more test data, please contact us.)
The Bendix AD-9 air dryer with oil coalescing is over 3 times better than the WABCO SS1200P with Air System Protector oil coalescing
What does this level of performance mean for you?
The preservation of your advanced new vehicle systems, the protection of your investment, and the money savings that comes with fewer replacements of your air dryer cartridge.
Bendix PuraGuard Oil Coalescing Cartridge Application Guide
Air dryer cartridge part numbers shown in blue provide the increased performance of Bendix PuraGuard oil coalescing technology
Vehicle Make Air Dryer Service New Reman Service New Reman Service New Pre-2004 Pre-EPA '04 AD-9 AD-IP AD-IS K046130, K060308, K058785, K060310, K020366, Vehicle Year 2004 - - 2009 Emission Standard EPA '04 EPA '2010 & newer EPA '10
K046130 K060308 K058785 K060310 K020366

Volvo/Mack

NOTE: PuraGuard Coalescing Cartridges required for all models beginning in 2008 model year.
AD-9 Freightliner & Western Star AD-IP DRM / AD-IS Service New Reman Service New Reman Service New K046130, K060308, K058785, K060310, K020366, 5008414
NOTE: PuraGuard Coalescing Cartridges required for all vehicles equipped with Detroit Diesel DD-13 and DD-15 engines, beginning in 2010 model year.
Kenworth & Peterbilt AD-IS AD-SP AD-IS EverFlow AD-9 AD-IP / AD-IP EverFlow AD-IP AD-IS AD-9 / AD-9 EP / AD-9 EverFlow
Service New Service New Reman Service New Reman Service New Reman Service New Service New Reman Service New Reman Service New
K020366, K046130, K060308, K058785, K060310, K058785, K060310, K020366, K046130, K060308, K058785, K060310, K020366,

5008414

International

Bus/RV/ Other

AD-IP / AD-IP EP / AD-IP EverFlow
AD-IS / AD-IS EP / AD-IS EverFlow
NOTE: Consult manufacturer specifications to verify the specific application cartridge requirement, PuraGuard oil coalescing cartridges are recommended by Bendix.
Be sure to replace your existing oil coalescing cartridges with Genuine Bendix service replacement parts & kits.
For more information, to meet with a salesperson, or to arrange a purchase, call 1800AIRBRAKE (18002472725) or visit www.bendix.com today.
References in this document to DETROIT DIESEL, FREIGHTLINER, INTERNATIONAL, KENWORTH, MACK, NAVISTAR, PACCAR, PETERBILT, VOLVO, WABCO, WESTERN STAR, and any other company or trademark are solely for identification and cross reference purposes. The trademarks are the property of their respective companies and are not affiliated with or endorsing Bendix Commercial Vehicle Systems LLC.

Bendix Commercial Vehicle Systems LLC 901 Cleveland Street Elyria, OH 44035 1-800-AIR-BRAKE www.bendix.com BWBendix Commercial Vehicle Systems LLC, a member of the Knorr-Bremse Group 03/11 All Rights Reserved

This troubleshooting guide obsoletes and supersedes all previous published troubleshooting information relative to Bendix air compressors.
Advanced Troubleshooting Guide for Air Brake Compressors
* The guide consists of an introduction to air brake charging system components, a table showing recommended vehicle maintenance schedules, and a troubleshooting symptom and remedy section with tests to diagnose most charging system problems.
Symptom Air Air brake charging system: Slow build (9.0). 9 - 10 Doesnt build air (10.0). 11 Air dryer: Doesnt purge (14.0). 12 Safety valve releases air (12.0). 12 Compressor: Constantly cycles (15.0). 13 Leaks air (16.0). 13 Safety valve releases air (11.0). 11 Noisy (18.0). 13 Reservoir: Safety valve releases air (13.0). 12 Page Number Symptom Coolant Compressor leaks coolant (17.0). 13 Engine Oil consumption (6.0). 9 Oil Oil Test Card results (1.0). 4 Oil is present: On the outside of the compressor (2.0). 5 At the air dryer purge/exhaust or surrounding area (3.0). 5 In the supply reservoir (4.0). 6 - 8 At the valves (5.0). 8 At air dryer cartridge (7.0). 9 In the ping tank or compressor discharge aftercooler (8.0). 9 Page Number

Test Procedures

(1) Oil Leakage at Head Gasket. 14 (2) System Leakage. 14 (3) Compressor Discharge and Air Dryer Inlet Temperature. 14 (4) Governor Malfunction. 14 (5) Governor Control Line. 15 (6) Compressor Unloader. 15 BASIC Test Information. 17-20
Maintenance & Usage Guidelines
Maintenance Schedule and Usage Guidelines (Table A). 3
*This guide is only for vehicles that use desiccant air dryers.
Introduction to the Air Brake Charging System
Powered by the vehicle engine, the air compressor builds the air pressure for the air brake system. The air compressor is typically cooled by the engine coolant system and lubricated by the engine oil supply. The compressor's unloader mechanism and governor (along with a synchro valve for the Bendix DuraFlo 596 air compressor) control the brake system air pressure between a preset maximum and minimum pressure level by monitoring the pressure in the service (or supply) reservoir. When the air pressure becomes greater than that of the preset cut-out, the governor controls the unloader mechanism of the compressor to stop the compressor from building air and also causes the air dryer to purge. As the service reservoir air pressure drops to the cut-in setting of the governor, the governor returns the compressor back to building air and the air dryer to air drying mode. As the atmospheric air is compressed, all the water vapor originally in the air is carried along into the air system, as well as a small amount of the lubricating oil as vapor. The duty cycle is the ratio of time the compressor spends building air to the total engine running time. Air compressors are designed to build air (run loaded) up to 25% of the time. Higher duty cycles cause conditions that affect air brake charging system performance which may require additional maintenance. Factors that add to the duty cycle are: air suspension, additional air accessories, use of an undersized compressor, frequent stops, excessive leakage from fittings, connections, lines, chambers or valves, etc. The discharge line allows the air, water-vapor and oil-vapor mixture to cool between the compressor and air dryer. The typical size of a vehicle's discharge line, (see column 2 of Table A on page 3) assumes a compressor with a normal (less than 25%) duty cycle, operating in a temperate climate. See Bendix and/or other air dryer manufacturer guidelines as needed. When the temperature of the compressed air that enters the air dryer is within the normal range, the air dryer can remove most of the charging system oil. If the temperature of the compressed air is above the normal range, oil as oil-vapor is able to pass through the air dryer and into the air system. Larger diameter discharge lines and/or longer discharge line lengths can help reduce the temperature. The discharge line must maintain a constant slope down from the compressor to the air dryer inlet fitting to avoid low points where ice may form and block the flow. If, instead, ice blockages occur at the air dryer inlet, insulation may be added here, or if the inlet fitting is a typical 90 degree fitting, it may be changed to a straight or 45 degree fitting. For more information on how to help prevent discharge line freeze-ups, see Bendix Bulletins TCH-08-21 and TCH-08-22 (see pages 20-22). Shorter discharge line lengths or insulation may be required in cold climates. The air dryer contains a filter that collects oil droplets, and a desiccant bed that removes almost all of the remaining water vapor. The compressed air is then passed to the air brake service (supply) reservoir. The oil droplets and the water collected are automatically purged when the governor reaches its cut-out setting. For vehicles with accessories that are sensitive to small amounts of oil, we recommended installation of a Bendix PuraGuard system filter, designed to minimize the amount of oil present.

12 or less

3/4 in.
Footnotes: 1 With increased air demand the air dryer cartridge needs to be replaced more often. 2 Use the drain valves to slowly drain all reservoirs to zero psi. 3 Allow the oil/water mixture to fully settle before measuring oil quantity. 4 To 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-08-21 and TCH-08-22, included in Appendix B, for more information.) 5 For 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.
Air Brake Charging System Troubleshooting
How to use this guide: Find the symptom(s) that you see, then move to the right to find the possible causes (What it may indicate) and remedies (What you should do). Review the warranty policy before performing any intrusive compressor maintenance. Unloader or cylinder head gasket replacement and resealing of the bottom cover plate are usually permitted under warranty. Follow all standard safety procedures when performing any maintenance. Look for: Normal - Charging system is working within normal range. Check - Charging system needs further investigation.
WARNING! Please READ and follow these instructions to avoid personal injury or death: When working on or around a vehicle, the following general precautions should be observed at all times. 1. Park the vehicle on a level surface, apply the parking brakes, and always block the wheels. Always wear safety glasses. 2. Stop the engine and remove ignition key when working under or around the vehicle. When working in the engine compartment, the engine should be shut off and the ignition key should be removed. Where circumstances require that the engine be in operation, EXTREME CAUTION should be used to prevent personal injury resulting from contact with moving, rotating, leaking, heated or electrically charged components. 3. Do not attempt to install, remove, disassemble or assemble a component until you have read and thoroughly understand the recommended procedures. Use only the proper tools and observe all precautions pertaining to use of those tools. 4. If the work is being performed on the vehicles air brake system, or any auxiliary pressurized air systems, make certain to drain the air pressure from all reservoirs before beginning ANY work on the vehicle. If the vehicle is equipped with an AD-IS air dryer system or a dryer reservoir module, be sure to drain the purge reservoir.

5. Following the vehicle manufacturers recommended procedures, deactivate the electrical system in a manner that safely removes all electrical power from the vehicle. 6. Never exceed manufacturers recommended pressures. 7. Never connect or disconnect a hose or line containing pressure; it may whip. Never remove a component or plug unless you are certain all system pressure has been depleted. 8. Use only genuine Bendix replacement parts, components and kits. Replacement hardware, tubing, hose, fittings, etc. must be of equivalent size, type and strength as original equipment and be designed specifically for such applications and systems. 9. Components with stripped threads or damaged parts should be replaced rather than repaired. Do not attempt repairs requiring machining or welding unless specifically stated and approved by the vehicle and component manufacturer. 10. Prior to returning the vehicle to service, make certain all components and systems are restored to their proper operating condition. 11. For vehicles with Antilock Traction Control (ATC), the ATC function must be disabled (ATC indicator lamp should be ON) prior to performing any vehicle maintenance where one or more wheels on a drive axle are lifted off the ground and moving.

Symptom:

1.0 Oil Test Card Results

What it may indicate:

Not a valid test.

What you should do:

Discontinue using this test. Do not use this card test to diagnose compressor "oil passing" issues. They are subjective and error prone. Use only the Bendix Air System Inspection Cup (BASIC) test and the methods described in this guide for advanced troubleshooting. The Bendix BASIC test should be the definitive method for judging excessive oil fouling/oil passing. (See Appendix A, on page 17 for a flowchart and expanded explanation of the checklist used when conducting the BASIC test.)

Bendix BASIC Test

2.0 Oil on the Outside of the Compressor 2.1 Oil leaking at compressor / engine connections:
Engine and/or other accessories leaking onto compressor. (a)Leak at the front or rear (fuel pump, etc.) mounting flange. (b)Leak at air inlet fitting. (c)Leak at air discharge fitting. (d)Loose/broken oil line fittings.
Find the source and repair. Return the vehicle to service. Repair or replace as necessary. If the mounting bolt torques are low, replace the gasket. Replace the fitting gasket. Inspect inlet hose and replace as necessary. Replace gasket or fitting as necessary to ensure good seal. Inspect and repair as necessary.
2.2 Oil leaking from compressor:
(a)Excessive leak at head gasket. (b)Leak at bottom cover plate. (c)Leak at internal rear flange gasket. (d)Leak through crankcase. (e)(If unable to tell source of leak.)

Go to Test 1 on page 14. Reseal bottom cover plate using RTV silicone sealant. Replace compressor. Replace compressor. Clean compressor and check periodically.
Head gasket and rear flange gasket locations.
3.0 Oil at air dryer purge/exhaust or surrounding area
Air brake charging system functioning normally.
Air dryers remove water and oil from the air brake charging system. Check that regular maintenance is being performed. Return the vehicle to service. An optional kit (Bendix piece number 5011327 for the Bendix AD-IS or AD-IP air dryers, or 5003838 for the Bendix AD-9 air dryer) is available to redirect the air dryer exhaust.
4.0 Oil in Supply or Service Reservoir (air dryer installed)
(If a maintained Bendix PuraGuard system filter or Bendix PuraGuard QC oil coalescing filter is installed, call 1-800-AIR-BRAKE (1-800-247-2725) and speak to a Tech Team member.)
Maintenance (a) If air brake charging system maintenance has not been performed. That is, reservoir(s) have not been drained per the schedule in Table A on page 3, Column 4 and/or the air dryer maintenance has not been performed as in Column 3. (b) If the vehicle maintenance has been performed as recommended in Table A on page 3, some oil in the reservoirs is normal. (a)
Drain all air tanks and check vehicle at next service interval using the Bendix BASIC test. See Table A on page 3, column 3 and 4, for recommended service schedule.
See Table A, on page 3, for maintenance schedule information. Drain all air tanks (reservoirs) into the Bendix BASIC test cup. (Bendix kit P/N 5013711).
Drain all air tanks into Bendix BASIC test cup (Bendix Air System Inspection Cup). If less than one unit of reservoir contents is found, the vehicle can be returned to service. Note: If more than one oil unit of water (or a cloudy emulsion mixture) is present, change the vehicle's air dryer, check for air system leakage (Test 2, on page 14), stop inspection and check again at the next service interval. See the BASIC test kit for full details. If less than one "oil unit" of water (or water/ cloudy emulsion mixture) is present, use the BASIC cup chart on the label of the cup to determine if the amount of oil found is within the acceptable level. If within the normal range, return the vehicle to service. For vehicles with accessories that are sensitive to small amounts of oil, consider a Bendix PuraGuard QC oil coalescing filter. If outside the normal range go to Symptom 4.0(c). Also see the Table A on page 3, column 3 for recommended air dryer cartridge replacement schedule.
Duty cycle too high (c) Air brake system leakage. (d) Compressor may be undersized for the application. The duty cycle is the ratio of time the compressor spends building air to total engine running time. Air compressors are designed to build air (to "run loaded") up to 25% of the time. Higher duty cycles cause conditions that affect air brake charging system performance which may require additional maintenance. Factors that add to the duty cycle are: air suspension, additional air accessories, use of an undersized compressor, frequent stops, excessive leakage from fittings, connections, lines, chambers or valves, etc. 6 Go to Test 2 on page 14. See Table A, column 1, on page 3 for recommended compressor sizes. If the compressor is "too small" for the vehicle's role (for example, where a vehicle's use has changed or service conditions exceed the original vehicle or engine OE spec's) then upgrade the compressor. Note: The costs incurred (e.g. installing a larger capacity compressor, etc.) are not covered under original compressor warranty. If the compressor is correct for the vehicle, go to Symptom 4.0 (e).

(d) Compressor unloader mechanism malfunction. (e) Damaged gasket. compressor head
9.0 Air brake charging system seems slow to build pressure. (continued)
(f) Restricted discharge line.
If discharge line is restricted: By more than 1/16" carbon build up, replace the discharge line (see Table A, column 2, on page 3 for recommended size) and go to Test 3 on page 14. By other restrictions (e.g. kinks). Replace the discharge line. See Table A, column 2, on page 3 for recommended size. Retest for air build. Return vehicle to service or, if problem persists, go to 9.0(a). The discharge line must maintain a constant slope down from the compressor to the air dryer inlet fitting to avoid low points where ice may form and block the flow. If, instead, ice blockages occur at the air dryer inlet, insulation may be added here, or if the inlet fitting is a typical 90 degree fitting, it may be changed to a straight or 45 degree fitting. For more information on how to help prevent discharge line freeze-ups, see Bendix Bulletins TCH-08-21 and TCH-08-22 (Appendix B). Shorter discharge line lengths or insulation may be required in cold climates. Check compressor air inlet line for restrictions, brittleness, soft or sagging hose conditions etc. Repair as necessary. Refer to vehicle manufacturers guidelines for inlet line size. Check the engine air filter and service if necessary (if possible, check the air filter usage indicator).

Dash gauges.

(g) Restricted air inlet (not enough air to compressor).
(h) Poorly filtered inlet air (poor air quality to compressor).
Check for leaking, damaged or defective compressor air inlet components (e.g. induction line, fittings, gaskets, filter bodies, etc.). Repair inlet components as needed. Note: Dirt ingestion will damage compressor and is not covered under warranty. Replace the compressor only after making certain that none of the preceding conditions, 9.0 (a) through 9.0 (h), exist.
(i) Compressor malfunction.
10.0 Air charging system doesnt build air.
(a) Governor malfunction*. (b) Restricted discharge line. (c) Air dryer heater malfunction: exhaust port frozen open. (d) Compressor malfunction.
Go to Test 4 on page 15. See 9.0(f). Replace air dryer heater. Replace the compressor only after making certain the preceding conditions do not exist.

* Note: For the Bendix DuraFlo 596 air compressor, not only the governor, but also the SV-1 synchro valve used would need to be tested. See Bulletin TCH-001-048.
11.0 Compressor safety valve releases air (Compressor builds too much air).
(a) Restricted discharge line.
If discharge line is restricted: By more than 1/16" carbon build up, replace the discharge line (see Table A, column 2, on page 3 for recommended size) and go to Test 3 on page 14. By other restrictions (e.g. kinks). Replace the discharge line. See Table A, column 2, on page 3 for recommended size. The discharge line must maintain a constant slope down from the compressor to the air dryer inlet fitting to avoid low points where ice may form and block the flow. If, instead, ice blockages occur at the air dryer inlet, insulation may be added here, or if the inlet fitting is a typical 90 degree fitting, it may be changed to a straight or 45 degree fitting. For more information on how to help prevent discharge line freeze-ups, see Bendix Bulletins TCH08-21 and TCH-08-22 (Appendix B). Shorter discharge line lengths or insulation may be required in cold climates. Inspect air lines and verify check valves are operating properly. Ensure discharge line is installed into the inlet of the air dryer and delivery is routed to the service reservoir. Verify relief pressure is 250 psi. Replace if defective. Go to Test 6 on page 15. Go to Test 4 on page 15.
Damaged discharge line shown.
(b) Downstream air brake system check valves or lines may be blocked or damaged. (c) Air dryer lines incorrectly installed.
(d) Compressor safety valve malfunction. (e) Compressor unloader mechanism malfunction. (f) Governor malfunction.
12.0 Air dryer safety valve releases air. Air dryer safety valve
(a) Restriction between air dryer and reservoir. (b) Air dryer safety valve malfunction.
Inspect delivery lines to reservoir for restrictions and repair as needed. Verify relief pressure is at vehicle or component manufacturer specifications. Replace if defective. See Maintenance Schedule and Usage Guidelines (Table A, column 3, on page 3). Verify operation of air dryer. Follow vehicle O.E. maintenance recommendations and component Service Data information. Go to Test 5 on page 15. Go to Test 4 on page 15. Verify relief pressure is at vehicle or component manufacturer's specifications (typically 150 psi). Replace if defective. Go to Test 4 on page 15. Go to Test 6 on page 15. Verify operation of air dryer. Follow vehicle O.E. maintenance recommendations. Go to Test 4 on page 15. Go to Test 2 on page 14. Go to Test 5 on page 15. Available reservoir capacity may be reduced by build up of water etc. Drain and perform routine maintenance per Table A, columns 3 & 4, on page 3. Go to Test 6 on page 15. Verify operation of air dryer. Follow vehicle O.E. maintenance recommendations and component Service Data information. Go to Test 2 on page 14.

Technician removes governor.
13.0 Reservoir safety valve releases air
14.0 Air dryer doesnt purge. (Never hear exhaust from air dryer.)
15.0 Compressor constantly cycles (compressor remains unloaded for a very short time.)

(c) Air dryer performed.

maintenance
(d) Air dryer malfunction.
(e) Improper governor control line installation to the reservoir. (f) Governor malfunction. (a) Reservoir safety valve malfunction.
(b) Governor malfunction. (c) Compressor unloader mechanism malfunction. (a) Air dryer malfunction. (b) Governor malfunction. (c) Air brake system leakage. (d) Improper governor control line installation to the reservoir. (a) Air brake charging system maintenance not performed.
(b) Compressor unloader mechanism malfunction. (c) Air dryer purge valve or delivery check valve malfunction. (d) Air brake system leakage.
16.0 Compressor leaks air
(a) Compressor leaks connections or ports. air at
Check for leaking, damaged or defective compressor fittings, gaskets, etc. Repair or replace as necessary. Go to Test 6 on page 15. An air leak at the head gasket may indicate a downstream restriction such as a freezeup or carbon blockage and/or could indicate a defective or missing safety valve. Find blockage (go to 9.0(f) for details.) and then replace the compressor. Do not re-use the safety valve without testing. See Symptom 12.0(a).
(b) Compressor unloader mechanism malfunction. (c) Damaged gasket.
Testing for leaks with soap solution.
compressor Head gasket location
17.0 Compressor leaks coolant
(a) Improperly installed plugs or coolant line fittings.

(b) Damaged gasket.

compressor
(c) Porous compressor head casting.
18.0 Noisy compressor (Multi-cylinder compressors only)

(a) Damaged compressor.

Other Miscellaneous Areas to Consider This guide attempts to cover most compressor system problems. Here are some rare sources of problems not covered in this guide: Turbocharger leakage. Lubricating oil from leaking turbocharger seals can enter the air compressor intake and give misleading symptoms. 13 Where a compressor does not have a safety valve installed, if a partial or complete discharge line blockage has occurred, damage can occur to the connecting rod bearings. Damage of this kind may not be detected and could lead to compressor problems at a later date.

Inspect for loose or over-torqued fittings. Reseal and tighten loose fittings and plugs as necessary. If overtorqued fittings and plugs have cracked ports in the head, replace the compressor. An air leak at the head gasket may indicate a downstream restriction such as a freezeup or carbon blockage and/or could indicate a defective or missing safety valve. Find blockage (go to 9.0(f) for details.) and then replace the compressor. Do not re-use the safety valve without testing. See Symptom 12.0(a). If casting porosity is detected, replace the compressor. Replace the compressor.
Test 1: Excessive Oil Leakage at the Head Gasket
Exterior leaks at the head gasket are not a sign that oil is being passed into the air charging system. Oil weepage at the head gasket does not prevent the compressor from building air. Observe the amount of weepage from the head gasket. If the oil is only around the cylinder head area, it is acceptable (return the vehicle to service), but, if the oil weepage extends down to the nameplate area of the compressor, the gasket can be replaced.

LOOK FOR WEEPAGE

Test 2: Air Brake System and Accessory Leakage
Inspect for air leaks when working on a vehicle and repair them promptly. Park the vehicle on level ground and chock wheels. Build system pressure to governor cut-out and allow the pressure to stabilize for one minute. Step 1: Observe the dash gauges for two additional minutes without the service brakes applied. Step 2: Apply the service brakes and allow the pressure to stabilize. Continue holding for two minutes (you may use a block of wood to hold the pedal in position.) Observe the dash gauges. If you see any noticeable decrease of the dash air gauge readings (i.e. more than 4 psi, plus two psi for each additional trailer) during either two minute test, repair the leaks and repeat this test to confirm that they have been repaired. Air leaks can also be found in the charging system, parking brakes, and/or other components - inspect and repair as necessary.
Test 3: Air Compressor Discharge Temperature and Air Dryer Inlet Temperature*
Note: The temperatures used in this test are not normal vehicle conditions. Above normal temperatures can cause oil (as vapor) to pass through the air dryer into the air brake system. This test is run with the engine at normal operating temperature, with engine at max. rpm. If available, a dyno may be used. 1. Allow the compressor to build the air system pressure to governor cut-in. 2. Pump the brakes to bring the dash gauge pressure to 90 psi. 3. Allow the compressor to build pressure from 95 to 105 psi gauge pressure and maintain this pressure range by cycling the brakes for five (5) minutes.
(* Note that only vehicles that have passed Test 2 would be candidates for this test.) 4. Then, while maintaining max rpm and pressure range, measure and record the surface temperature of the fittings: at the compressor discharge port. (T1). at the air dryer inlet fitting. (T2). Use a touch probe thermocouple for measuring the temperature. 5. See table below. 6. Retest before returning the vehicle to service.

T2 Action

Temperatures are within normal range for this test, check other symptoms. Go to 4.0 (h). This could indicate a discharge line problem (e.g. restriction). Call 1-800-AIR-BRAKE (1-800-247-2725) and speak with our Tech Team. Compressor is running hot. Check coolant 4(f) and/or discharge line 4(g).
Compressor Air Dryer Discharge Inlet Fitting Fitting

under 360F under 360F

under 200F over 200F

over 360F __

Discharge Line 14

Tests (continued)

Test 4: Governor Malfunction
1. Inspect control lines to and from the governor for restrictions (e.g. collapsed or kinked). Repair as necessary. 2. Using a calibrated external gauge in the supply reservoir, service reservoir, or reservoir port of the D-2 governor, verify cut-in and cutout pressures are within vehicle OEM specification. 3. If the governor is malfunctioning, replace it.
Test 5: Governor Control Line
1. Ensure that the governor control line from the reservoir is located at or near the top of the reservoir. (This line, if located near the bottom of the reservoir, can become blocked or restricted by the reservoir contents e.g. water or ice.) 2. Perform proper reservoir drain intervals and air dryer cartridge maintenance per Maintenance Schedule and Usage Guidelines (Table A on page 3). 3. Return the vehicle to service.
Test 6: Compressor Unloader Leakage
Bendix Compressors: Park vehicle, chock wheels, and follow all standard safety procedures. Remove the governor and install a fitting to the unloader port. Add a section of air hose (min 1ft long for a 1/2" diameter line) and a gauge to the fitting followed by a shut-off valve and an air source (shop air or small air tank). Open the shut off and charge the unloader port by allowing air pressure to enter the hose and unload the compressor. Shut off the air supply and observe the gauge. A steady reading indicates no leakage at the unloader port, but a falling reading shows that the unloader mechanism is leaking and needs to be serviced.
Appendix A: Information about the BASIC Test Kit (Bendix P/N 5013711)
Service writer records info - including the number of days since all air tanks were drained - and fills out symptom checklist. Technician inspects items.

Bendix Air System Inspection Cup (BASIC) Test Information
START BASIC TEST Park vehicle on LEVEL ground. Chock wheels, drain air from system.
Drain contents of ALL air tanks into BASIC cup
Is there less than one unit of liquid? NO Is there more than one unit of: water, or cloudy emulsion mixture?
Vehicle OK. Return vehicle to service.

END TEST

Cloudy emulsion mixture
NO, only oil. YES, this is a high air use vehicle. Is this a transit vehicle, bulk unloader, or has more than 5 axles? NO, this is a low air use vehicle. Is this vehicle being re-tested (after water, etc. was found last time?)
Find the point on the label where the number of oil units meets the number of days* since the vehicle's air tanks were last drained.
Go to the Advanced Troubleshooting Guide to find reason(s) for presence of water
Change air dryer cartridge**
Is the point above the HIGH Air Use line on the cup?
Is the point above the LOW Air Use line on the cup? NO

Test for air leakage

Use Test 2: Air Leakage
Re-test with the BASIC Test after 30 days***
Does the vehicle have excessive air leakage? NO Was the number of days since last draining known?
Repair leaks and return vehicle to service
* If the number of days since the air tanks were drained is unknown - use the 30 day line. ** Note: Typical air dryer cartridge replacement schedule is every 3 yrs/ 300K miles for low air use vehicles and every year/100K miles for high air use vehicles.
NO (did not know when last drained) Re-test with the BASIC Test after 30 days***
YES, number of days was known (30 - 90 days)

Compressor

Replace the Compressor. If under warranty, follow standard procedures. If, after a compressor was already replaced, the vehicle fails the BASIC test again, do not replace the compressor**** - use the Advanced Troubleshooting Guide to investigate the cause(s).
*** To get an accurate reading for the amount of oil collected during a 30 day period, ask the customer not to drain the air tanks before returning. (Note that 30-90 days is the recommended air tank drain schedule for vehicles equipped with a Bendix air dryer that are properly maintained.) If, in cold weather conditions, the 30 day air tank drain schedule is longer than the customer's usual draining interval, the customer must determine, based on its experience with the vehicle, whether to participate now, or wait for warmer weather. See the cold weather tips in Bulletins TCH-008-21 and TCH-008-22 (included on pages 20-22 of this document). ****Note: After replacing a compressor, residual oil may take a considerable period of time to be flushed from the air brake system.

Appendix A continued: Information about the BASIC Test Kit (Bendix P/N 5013711)
Filling in the Checklist for the Bendix Air System Inspection Cup (BASIC) Test
Note: Follow all standard safety precautions. For vehicles using a desiccant air dryer.
The Service Writer fills out these fields with information gained from the customer Number of Days Since Air Tanks Were Last Drained: ________ Date: ___________Vehicle #: ____________ Engine SN __________________________ Vehicle Used for: _______________Typical Load:________ (lbs.) No. of Axles: ____ (tractor) ____ (trailer) No. of Lift Axles: ____ Technicians Name: ____________________ Checklist for Technician Relay valve q leaks oil / q malfunctions. q no q yes* Dash valve q leaks oil / q malfunctions. q no q yes* q Air dryer leaks oil. q no q yes* q Governor malfunction. q no q yes* q Oil in gladhands. q no q yes* how much oil did you find? ________________________________ q Oil on ground or vehicle exterior. q no q yes* amount described: ______________________________________ q Short air dryer cartridge life replaces every: ______________ q miles, q kms, or q months q Oil in air tanks amount described:_______________________
We will measure amount currently found when we get to step B of the test.
Customers Complaint (Please check all that apply) Have you confirmed complaint?
The Service Writer also checks off any complaints that the customer makes to help the Technician in investigating.
The Technician checks boxes for any of the complaints that can be confirmed.
q Excessive engine oil loss amount described: ______________ Is the engine leaking oil?. q no q yes* Is the compressor leaking oil?. q no q yes* q Other complaint: ______________________________________ q No customer complaint.
* Note: A confirmed complaint above does NOT mean that the compressor must be replaced. The full BASIC test below will investigate the facts.

BASIC test starts here:

STEP A - Select one:
q This is a low air use vehicle: Line haul (single trailer) with 5 or less axles, or q This is a high air use vehicle: Garbage truck, transit bus, bulk unloader, or line haul with 6 or more axles. Then go to Step B.
The Technician selects the air use category for the vehicle. This decided which of the two acceptance lines on the cup will be used for the test below. For an accurate test, the contents of all the air tanks on the vehicle should be used. Note for returning vehicles that are being retested after a water/cloudy emulsion mixture was found last time and the air dryer cartridge replaced: If more than one oil unit of water or a cloudy emulsion mixture is found again, stop the BASIC test and consult the air dryer's Service Data sheet troubleshooting section.

STEP B - Measure the Charging System Contents
1. Park and chock vehicle on level ground. Drain the air system by pumping the service brakes. 2. Completely drain ALL the air tanks into a single BASIC cup. 3. If there is less than one unit of contents total, end the test now and return the vehicle to service. Vehicle passes. 4. If more than one oil unit of water (or a cloudy emulsion mixture) is found: (a) Change the vehicles air dryer cartridge Oil - see Footnote 1, Units (b) Conduct the 4 minute leakage test (Step D), (c) STOP the inspection, and check the vehicle again after 30 days - see Footnote 2. STOP Otherwise, go to Step C.
Footnote 1: Note: Typical air dryer cartridge replacement schedule is every 3 yrs/ 300K miles for low air use vehicles and every year/100K miles for high air use vehicles. Footnote 2: To get an accurate reading for the amount of oil collected during a 30 day period, ask the customer not to drain the air tanks before returning. (Note that 30-90 days is the recommended air tank drain schedule for vehicles equipped with a Bendix air dryer that are properly maintained.) If, in cold weather conditions, the 30 day air tank drain schedule is longer than the customer's usual draining interval, the customer must determine, based on its experience with the vehicle, whether to participate now, or wait for warmer weather. See the cold weather tips in Bulletins TCH-008-21 and TCH-008-22 (included in Appendix B of the advanced troubleshooting guide).
STEP C - How to Use the BASIC Test
The Technician uses the chart (label) on the BASIC test cup to help decide the action to take, based on the amount of oil found. Use the lower acceptance line for low air use vehicles, and upper line for high air use vehicles (from Step A).
1. Record days since air tanks were last drained. _________ days
2. Record amount of oil found: _________ units

3. Action to take

if oil level is at or below System OK. STOP If number of days is: acceptance line for number TEST 30-60 days (high air Return to service. of days use) or if oil level is above 30-90 days (low air use) Go to Step D acceptance line for number of days if oil level is at or below System OK. STOP TEST 30-day acceptance line Return to service. Stop inspection. (if the number of days is STOP unknown, or outside the if oil level is above 30-day Test again acceptance line after 30 days. + CK. limits above) See Footnote 2.