AIR CLEANER 4B9127 - Caterpillar

Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
Reports have been received from the field that air leak of 48 kPa (7 psi) occurs between bead seat band assembly and rim base on outboard side of wheel. This is due to undersized rim which prevents the o-ring from sealing and leads to leakage of air.The air leak also occur on inboard side of rim between tire and flange caused by insufficient interference between tires and rims.Solution
Caterpillar is aware of this problem, and is recommending the following interim corrective action.
To improve the detectability of the leaks, inflate the tire back to recommended pressure if possible. Inspect the seals between the tire and rim by filling with soap and water solution and locate the place where the leak is occurring. Record the location of the leak.
If continuous bubbling occurs between the lock ring and bead seat band assembly in one or more places on outboard side of wheel, measure and record the gap between the nearest parts of the lock ring ends while the lock ring is installed on the rim with an inflated tire.
Record the date stamp of the rim base that is located near the valve access hole on the rim in the format MM/YY.
Replace the former lock ring with CAT ® part number 7D-7469 Lock Ring .
Inspect the o-ring seal for pinch or cut damage. Replace the o-ring if necessary.
Inflate the tire again, lower the machine, and inspect for air leak again. Again measure the gap between the nearest parts of the lock ring ends and record the new measurement.
If the leak still occurs, contact Dealer Solution Network (DSN) and create DSN documentation. If the leak has stopped, resume work and monitor air pressure for some time.
If continuous bubbling occurs between the flange and the rim base or between the tire and flange on the inboard side of the wheel, record the manufacturer, tread pattern, and serial number of the tire.
Record the date stamp of the rim base that is located near the valve access hole on the rim in the format MM/YY. Dismount and remount tires.
If the leak still occurs, contact DSN and create DSN documentation. If the leak has stopped, resume work and monitor air pressure for some time.
If the problem does not fall under Continuous Product Improvement (CPI) issue number 322505, contact DSN and create DSN documentation.