Having noticed a “rumble” type noise in the engine of my Cowley, I investigated and discovered that the crank had endplay of about 35 thou. (Ross Steel suggested it should be between 4 and 8 thou.). The remedy which I embarked upon, which I had used on the Cowley’s previous engine was as follows:-
Remove sump and measure with feeler gauges the clearance between the camshaft drive gear on the crankshaft and the front end of the front main bearing, with the crankshaft pushed/pulled into its furthest forward position.
Remove gear from crankshaft and machine recess in back of gear to accommodate “Timken NTA 2435” thrust bearing – approx size 2 ¼” x 1 ½” x 7/32”, making certain that thrust protruded from gear sufficiently to ensure endplay of approx. 2 thou.
Re-assemble and check clearance, replace sump, etc..
Apparently, crankshaft endplay is common in Cowleys, particularly if they have been fitted with stronger clutch springs (commercials have stronger springs as standard).
Perhaps this remedy may be of assistance to other Cowley/Oxford owners.