It is usually the case that the intermediate gear spindle bush is worn when a BSA B or M Series engine is stripped.
This spindle does not have a direct oil feed as do the cam spindles The spindle is hollow and oil mist from the crankcase is forced into the back of the spindle under crankcase pressure and out of a hole drilled through the side of the spindle to lubricate the bush.
An interesting point is whether the lubrication hole should be on the top or bottom of the spindle when fitted...the spindle is round and the hole can end up in any position.
I have always fitted the spindle with the hole at the bottom, working on the theory that any surplus oil will 'pool' in the bottom and find its way more easily to the bush...It is something to consider when refitting the spindle to the crankcase.
Any one have a view on this subject?
Another point if you can't get the correct bush...the small end bush for a B31/33/M33 is the same apart from being slightly longer...just file to length after fitting the bush to the gear and before reaming to finished size...Ian

email (option): ian@wright52.plus.com

Just cleaned my crankcase and noticed the hole is also at the bottom, and I am pretty sure there has not been messed with these cases. Also checked my other cases and the holes are all at the bottom. although on the exploded view in the service sheets from 1948 the hole seem to be drawn at the top ... (at least the oil-groove is)

Also noticed the thick hardened washer behind the spindle was loose and had a little play so I think it has been turning with the gear and damaged the aluminium a bit, it seems the locking of the ring only relies on the pressfit of the spindle during assembly...

There was also a little washer in front of the locking pin of the oilpump spindle, so that the pin can not slide back when the timing case is fitted, never seen that before, maybe in later engines they made the pin a bit longer so that the washer was not needed ??



Regards, Michiel

email (option): m.wijbenga@hotmail.com

That little washer is definitely shown in my workshop manual. Ron

email (option): ronpier@talk21.com

There seems to be some variation, albeit minor, in the lengths of the pins and the gasket face dimensions of the crankcases..some engines require this washer to make up the length, others not.
There are also completely different length (subtabtially shorter) pins which are for other engines I assume..though I haven't found out which ones...Ian

email (option): ian@wright52.plus.com