1997/07/28 Caterpillar

3508 (7YG, 99W),
3508B (2GR),
3512 (4WJ, 96Z),
3512B (8BR),
3516 (2PK, 54Z),
3516B (7TR) Machine Engines

This article replaces Service Magazine article published; November 18, 1991, page 5; "Check 1S-5485 Air Cleaner Dust Valve To Ensure Correct Operation".

Description:

The 1S-5485 Air Cleaner Dust Valve, located at the bottom of the precleaner cup assembly, is a component of the 9Y-8930 Air Cleaner Group. The purpose of the 1S-5485 Air Cleaner Dust Valve is to eject dust and dirt trapped by the precleaner.

Operation:

Typical view of the 9Y-8930 Air Cleaner Group. (1) 9W-9069 Precleaner Cup Assembly. (2) 1S-5485 Air Cleaner Dust Valve.

* The 2W-9069 Precleaner Cup Assembly (1) causes a swirling of air, separating and trapping most of the dust from the air before it reaches the primary element assembly and the secondary element assembly. The dust and dirt trapped by the 2W-9069 Cup Assembly drops to the bottom and is discharged when the 1S-5485 Air Cleaner Dust Valve (2) is in the OPEN position.

NOTE: The 1S-5485 Air Cleaner Dust Valve is open when the engine is OFF or idling.

* The 1S-5485 Air Cleaner Dust Valve is forced closed when the air pressure drops inside the 2W-9069 Precleaner Cup Assembly when the engine is under load.

Maintenance:

* The rubber 1S-5485 Air Cleaner Dust Valve can become hardened over a period of time. If the rubber becomes hardened, it does not open or close properly. The 2W-9069 Precleaner Cup Assembly can become ineffective and the air filter element assemblies may have a shortened life.

The following maintenance procedures are recommended:

* When replacing the secondary element assembly, the 2W-9069 Precleaner Cup Assembly should be removed and cleaned with pressurized air or water.

* The 1S-5485 Air Cleaner Dust Valve should be inspected and replaced if the rubber has become hard and not flexible.

NOTE: Do not apply any paint to the 1S-5485 Air Cleaner Dust Valve. Paint can cause the rubber to harden and not seal properly.