Securing screw to fit SOHC oil pump - with reduced head. Price is per pair.
These start life as the correct length and thread high tensile set screw - but with a normal hex head, which is wrong for a Norton oil pump screw. I then machine them to give them the correct reduced diameter - so they will fit in the counterbore of an original Norton oil pump and also give them the correct shallow face - so they do not obstruct the oil pump drive plate. Sorry they are not cheap, but are very labour intensive to make to this specification.
Please note: Check carefully when fitting these that the oil pump drive plate can turn freely and is not in any way catching the head of these screws. I say this because over the many years that the Norton cylindrical oil pump was made, there were slight variations of the brass cover on the oil pump. I have machined the heads of these screws to best fit a 'standard' size plate, but if your plate is shallower you may find the heads sit slightly proud. If this is the case it is possible to carefully linish or file the head of screw just a little more. Similarly - the counterbore diameter of oil pumps can also vary by a small margin, these have been made to the diameter that most original pumps were and are a nice size fit. If you find them a bit tight - fit a small flapwheel into an electric drill and spin the head of the set screw against the flapwheel until it fits.
As a final hint - removing the Norton oil pump from a SOHC crankcase is often a difficult (and stressfull!) task. If you are trying to do this for the first time - here a couple of tips:
- Do not try to remove the oil pump without first warming the crankcase (if it comes out 'cold' it is probably the wrong size oil pump!). I always place the crankcase in the oven timing case down. I heat the oven until it is 'spit hot' (you spit on it and the spit bounces back on you). If all good you should find the oil pump has dropped out on its own. If not - you can try carefully to pull on the drive tang with a good condition set of pliers or attach a mole grip. However - be very careful, if it does not want to easily pull out you risk damaging the oil pump drive tang. Also, if it does move - be careful to pull it out straight, or it can catch and get jammed
- If it still does not want to come out - first try putting two large wooden blocks on the garage floor and try banging the crankcase down while hot - this may jar the oil pump enough to move it
- If it still does not want to come out (and by this time you are probalby getting desperate!) - it is possible to carefully tap and thread the oil pump retaining screw holes. I seem to remember that 5/16" BSC is the size I tap them. It is then possible to screw two long 5/16 BSC studs into the oil pump body, then fit a 1" x 6" bar with two suitable holes in it over the studs, so that the bar drops down onto the gasket face of the timing case. Then by fitting washers and nuts it is normally possible to tighten the nuts (again with the crankcase heated) until the oil pump finally moves
In desperation I have seen crankcases where people have drilled the crankcase from behind the oil pump so that they can hammer the oil pump out with a punch. I cannot advise this . . . but if nothing else works understand why people do it. However, if you do this you will have to accept you will almost certainly ruin the pump or gears, and may damage the crankcases ( in fact you might as well just drill into the oil pump from the front with a bigger tap and do what I suggested above - at least that will just bugger the pump, hopefully not the crankcase!!
Best of luck, and although I do not offer oil pumps at this point in time - (June 2016), I do hope to be manufacturing them sometime in the future