If for any reason the coupling is dismantled or disconnected care must be taken in reassembly. On Freight-Passenger units the crankshaft tension keyway and the air compressor keyway must be aligned. On Road Switcher units these keyways must be 180 degs out of alignment. Lubrication fittings on the covers provide a means of forcing Marfak No. 3HD, or equivalent, into the coupling. The coupling is normally lubricated every 10,000 miles or monthly, however, if any noise should be detected from the coupling while the engine is running the condition should be reported and corrected at the first opportunity.
Insufficient lubrication is the most common cause of noise and wear.
It consists of a rigid half mounted on the compressor shaft and aflexible half, made up of a hub and sleeve, mounted on the fan drive shaft. The sleeve and hub are connected through teeth allowing the transmittal of power from one hub to the other. Crater Compound No. 1 or equivalent is normally added every 10,000 miles or monthly through a lubricating hole in the sleeve portion. If, however, noise is detected from the coupling with the engine running the conditions should be reported and corrected at the first opportunity. Insufficient lubrication is the most common cause of noise and wear.