BENDIX TCH-008-028 User Manual

Technical Bulletin

Bulletin No: TCH-008-028 Effective Date: 11/17/97 Cancels: TCH-008-027 Page: 1 of 5

Subject:

GENERAL

This is to announce the availability of new upgraded purge valve assemblies for the AD-9DI Drop-In and AD-IP air dryers.

Bendix Commercial Vehicle Systems LLC began using the new purge valve assemblies in production on November 1, 1997.

Because of the improvements made to the new purge valve assemblies we recommend that all affected AD-9DI and AD-IP air dryers be upgraded with the new purge valve subassemblies. Upgrades for in-service air dryers, as well as shelf stock of purge valve kits and service new and remanufactured exchange air dryers are available free of charge when the return procedure described in this bulletin is followed. Bendix strongly encourages all customers to take advantage of this valuable upgrade offer.

THE FOLLOWING TOPICS ARE COVERED IN THIS BULLETIN.

• SUMMARY OF PURGE VALVE ASSEMBLY IMPROVEMENTS

• PART NUMBER CHANGES

• WHAT IS ELIGIBLE FOR REPLACEMENT

• IDENTIFYING IN-SERVICE AIR DRYERS WITH LATEST PURGE VALVE ASSEMBLY

• OBTAINING A REPLACEMENT

AD-9DI & AD-IP Purge Valve Upgrade

Note: The AD-9DI is a specialized version of the AD-9 which is specifically designed for air systems where

the Holset (Cummins) type E or QE compressor was in use. See figure 3.

SUMMARY OF PURGE VALVE ASSEMBLY IMPROVEMENTS

AD-IP Air Dryer Purge Valve Assemblies The AD-IP purge valve assembly has been upgraded for improved temperature resistance. The changes which will eliminate recently reported incidents of intermittent sticking are:

1. A heavier purge piston return spring to assure positive closing.

2. A modified piston and seal combination for improved sealing at higher temperatures.

AD-9DI Drop-In Air Dryer Purge Valve Assemblies The AD-9DI purge valve assembly has been upgraded for improved temperature resistance required for Holset (Cummins) compressors which produce higher discharge temperatures. The changes which will eliminate recently reported incidents of intermittent sticking are:

1. A heavier purge piston return spring to assure positive closing.

2. A modified piston and seal combination for improved sealing at higher temperatures.

Page: 2 of 5

PART NUMBER CHANGES

The part numbers of AD-9DI and AD-IP air dryer assemblies have not been changed. The part numbers of the replacement purge valves have been changed to assist in identifying old and new inventory.

WHAT IS ELIGIBLE FOR REPLACEMENT

Replace purge valve assemblies as follows;

1. In-Service AD-9DI air dryers (i.e. installed on vehicles) that have a build date between October 1, 1996

(K0196T or F) and October 31, 1997 (K3197T or F). See note below for build date information.

2. In-Service AD-IP air dryers (i.e. installed on vehicles) that have a build date prior to L0197F (November 1,

1997). See note below for build date information. Note: The first letter of the date code is the month, J = September, K = October L = November etc. The first

pair of digits is the day while the second pair is the year. The last letter indicates the location of the plant that manufactured the unit as indicated by an “F” or a “T”. Plant origin is not pertinent to this upgrade.

3. Shelf stock of purge valve assemblies and specified kits at the fleet, dealer and independent parts distributor

should be replaced. The new purge valve assemblies have new part numbers assigned to them to distinguish them from the old assemblies. The part numbers involved are as follows;

AD-IP Air Dryer Kit Name Original Part Number New Part Number

Service New Purge Valve Assembly 065626 800404 Service New Purge Valve Assembly 800340 800404

AD-9DI Air Dryer Kit Name Original Part Number New Part Number

Service New Purge Valve Assembly 109569 – 12 volt 800405 – 12 volt Service New Purge Valve Assembly 109570 – 24 volt 5004338 – 24 volt Remanufactured Purge Valve Assembly 109686 – 12 volt 5004341 – 12 volt Remanufactured Purge Valve Assembly 109695 – 12 volt 5004342 – 24 volt Purge Valve Modification Kit 265088 5004380

Replace complete air dryer assemblies as follows; Shelf stock of air dryer assemblies at the fleet, dealer and independent parts distributor should be replaced as follows;

1. AD-9DI air dryers that have a build date between October 1, 1996 (K0196T or F) and October 31, 1997

(K3197T or F). See note below for build date information.

2. AD-IP air dryers that have a build date prior to L0197F (November 1, 1997). See note below for build date

information.

Note: The first letter of the date code is the month, J = September, K = October L = November etc. The first

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