The waterpump mounting slots were too wide and the washer was bending as the bolt was tightened. Therefore a made two steel rectangular washers for a more secure mounting.
I also installed the turnbuckle between the two units designed to ease the belt tension adjustment.
One final addition was to place a 1/8" roll pin through the base of the water pump casting and the through the airframe bracket to facilitate removal and replacement accuracy.
The three pulleys in this system are not perfectly level. I believe this is due to the alternator mounting rod welded to the airframe not being in the correct axis. I don't believe it is off enough to cause the belt to come off however I will have John Spurling take a look at some point.
