EK010 KSS/KTS ENGINE

I am rebuilding a MkII KSS Engine (No. 9091 - 1939?) for use in a Viper frame. I have run the engine and have a marked bevel whine! Having dismantled it again, the top bevels appear to make a whine when the large camshaft bevel is used to turn the set, but not if the shaft bevel is turned to drive the camshaft. Could this be the source of the whine? I have yet to look at the lower bevels again, but they were OK before I assembled it last time- not too tight or with any play - also meshing seemed good.
Further, are there two sizes of exhaust nut for these engines, the one I have (brass) seems to go into the head too far before meshing- both sets of threads look good?  - John Hoskins 18/6/2007

I had the following when rebuilding my Mk2 KSS engine. The engine had previously had a gear whine which I considered to be detrimental. I have had a bit of experience in the manufacture of truck axles. I rebuilt the engine using the same shims as before and had not stripped the camshaft out of its housing. The top bevels had a tight spot which I cured by seating the camshaft fully in the bearing at the non gear end and making sure that sealant on the cover plate did not build up on the end of the shaft and push the gears futher into mesh. - Ron Sabey 31/12/2007