52-20-02 WRIGHT: Applies to All Models C18BA and C18BD Engines.
Compliance required as soon as possible but not later than October 31, 1952.
To prevent crankpin sludge from washing into the master rod bearing oil supply passages causing failure of the bearing, the use of oil dilution must be discontinued and the dilution lines disconnected or removed. This restriction on oil dilution is to continue until an adequate sludge controlling device is developed and incorporated in these engines.