Since this obsession got rolling one matter that has always been in the back of my mind was how to run a total loss oil system on the street. Lowering the compression to run petrol is not a problem. Retiming the valves and ignition for at least a semi-normal tick over and tractable on the street will be interesting but not impossible.
One option suggested by a long time J.A.P. race mechanic was to run a hose nipple off the back of the oil collection tray to an oil tank. The concern is that while that is normal practice for using an oil collection bottle or tray for a track application; would there be enough pressure to flow up to an oil recirculation tank for the street.
I did find that some of the early two strokes from Japan had an external oil pump for the fuel oil mixture. The external pumps also run from a thimble nut like the Pilgrim and could be run from the magneto drive nut. The oil mixture pump was attractive because it also had an output adjustment. However it would hang an odd looking pump off the top of the timing cover.
Since I know enough, at this point, to be confused more questions seem to pop up. So I keep asking questions and looking for information, alternatives and solutions. To that end the Labor Day All British Field Meet in Portland was two days of unbelievable coincidences, happenstance and karma.
Along with the field meet is vintage racing. I guess my being a gear head and always looking at fast cars draws me to the racer pits. As I was drooling over all the exotic machines a saw the nose of a small open wheel racer that I immediately recognized. It was the nose of an early Cooper F3. Now my heart was in my throat because if the Cooper was early enough it would have a J.A.P. 4B or a twin in it. Rushing over I was absolutely thrilled to see a single.
All in all just a lovely engine
Safety wired to the hilt
The owner of the car wasn’t around but I was told by a pit mate that he had just finished a race and should be back soon. I hung around and very enthusiastically accosted the owner driver when he showed up in the person of Ed Millman from Seattle. Ed is the President of AdServices, http://www.adservices.com/. He is a very nice guy and is as obsessed with the J.A.P. engines as I am. Of course the difference between us is he runs his with four wheels as opposed to my two.
We talked and talked. Ed was impressed that I had a 600 SV on the street and really thought my idea of doing a street 4B was pretty cool. He was very gracious and in great detail talked about his engine and the cars history in New Zealand and its early history with a J.A.P. v-twin. The more we talked the more it became clear that I very well had some spares Ed could use. But as they say the other shoe dropped.
Ed realized that he might have the solution to my oil recirculation puzzle. Apparently while looking for parts on ebay (turn head, spit) Ed found an aftermarket oil scavenge pump which was designed to bolt up behind the Pilgrim pump and run off the timing gear thimble nut. He had tried to fit it but the pump pushed the Pilgrim out far enough that it would foul a tube of the frame. He was not about to modify the frame tube and so it got put in the spares box. Ed was not able to remember even why he had brought the pump along to the race. That pump was the clean answer to recovering oil to be recirculated for the street use of a 4B. Ed sold me the pump. It was my birthday all over again. Did I mention that I was thrilled and happy and probably acted like a complete idiot when Ed handed over the pump? Oh well!
Larger bottom tray for oil and Pilgrim with scavenge pump
Open face of scavenge pump
The pump has no makers mark on it and I have no idea how old it is. A pretty knowledgeable cycle restorer at the meet thought the pump gears looked like BSA but couldn’t be sure without some stare and compare. I have no idea. I just hope the pump works. I’m going to build a test board for a proof of operation for the pump combination. The thought is to build a backboard that the two pumps can be bolted to and then drive them at low speed from my lathe. I think it’s worth the effort to be sure both pumps work like they should before I trust the oil sensitive and friction adverse internal parts of a rebuilt engine to the combination. During this winter when my old bones are too frozen to work in the garage I will be making a drawing of the scavenge pump for future reference for both Ed and I.