I wonder if you have a twin start oil pump, Don't have a clue what I have ,
I built it in mid 70s.
I built it in mid 70s.
I always screw the chain oiler needle in the oil tank in tight to shut it off.Is the PR 40 needle to tight?
Thanks folks for comments so far. All rocker gear clear. Can easily blow through from A58 to cylinder head return in oil tank, so I have no idea where any back pressure could come from. I do have chromed oil pipes which could well be more slippy than optimum... however no problems since 1974!.. also I checked... no rodents... so I cant understand why suddenly now... my next move is to clamp each end of the hose down tight with crappy jubilee clips... if I don't get an oil gush from elsewhere I will do a bit of ferrule crimping!