Have just rebuilt my Norvin which has an oil supply in rear section of petrol tank. I needed to remove the tank to do some work which necessitated draining the oil cold (20/50 multigrade). The rate seemed very slow so I measured it and it took 18 minutes to drain one litre of oil. This was through a 1/4 inch opening in the standard Norton gauze oil filter. I checked it again with the original (Norton) gauze filter which was previously on the bike and has a 5/16 inch opening. With the larger opening it took 6 minutes to drain one litre of oil. Obviously the viscosity decreases as the oil heats up but as attested to by many people this takes a long time. Our local technical guru has calculated that the pump moves a little over a gallon per hour per 1,000 revs but we don't know how much (if any) suction is produced which is pulling the oil from the tank at a greater rate. If I'm relying on gravity alone then it might be excellent at pulling apples off trees but not for feeding the Vincent pump. Any suggestions, ideas, comments? I have opened the new filter to 5/16 and will use this with fingers crossed.
Rate of flow of oil from tank to pump
- Thread starter edward
- Start date
Some research was carried out on oil pressure some years back. I seem to remember that on the supply side from the pump to the engine you are looking at 2 3 lbs, if that, less when warm, the flow rate of the pump is low, it does not deen to be high as the engine is all ball or roller bearings, if we ignore cams and spindless... You will find lots more info in Forty Years On.
Have you joined the club yet, how abour some info specs and maybe a photo of the machine?
Jim Burgess, Norvin section organiser j.burgess998@btinternet.com
Have you joined the club yet, how abour some info specs and maybe a photo of the machine?
Jim Burgess, Norvin section organiser j.burgess998@btinternet.com
Edward,
The flow that you have sounds fine to me. Back in the late 60's Coburn Benson (Shown in another thread) had a big end failure at Harewood due to lack of oil. What he did not realize at the time was that the oil circulated very slowly and he was running 50w Castrol R. He did some trials and found that the oil in the tank circulated once every 45 minutes. Subsequently, he was much more careful about warm up and never had a problem. He never used two start pumps. His numbers are arguably similar to yours.
Many modern oils are far superior to cold starts thant the old oil. They provide a lot of protection with little or no flow. I have a stock oil pump on the racer and three filters. I have the stock Vincent filter, a Norton remote filter on the return hose and a small debris filter on the feed hose.
Jim is correct on the info to my knowlege, except the oil pressure is two to three pounds, which is what he meant but it may look like 23. In fact, roller bearings do not like to have too much oil although I think it takes more than a Vin engine can muster to get into that territory. I have had the big end fail from too much oil as a result of oil not being able to get out of the big end fast enough.
David
The flow that you have sounds fine to me. Back in the late 60's Coburn Benson (Shown in another thread) had a big end failure at Harewood due to lack of oil. What he did not realize at the time was that the oil circulated very slowly and he was running 50w Castrol R. He did some trials and found that the oil in the tank circulated once every 45 minutes. Subsequently, he was much more careful about warm up and never had a problem. He never used two start pumps. His numbers are arguably similar to yours.
Many modern oils are far superior to cold starts thant the old oil. They provide a lot of protection with little or no flow. I have a stock oil pump on the racer and three filters. I have the stock Vincent filter, a Norton remote filter on the return hose and a small debris filter on the feed hose.
Jim is correct on the info to my knowlege, except the oil pressure is two to three pounds, which is what he meant but it may look like 23. In fact, roller bearings do not like to have too much oil although I think it takes more than a Vin engine can muster to get into that territory. I have had the big end fail from too much oil as a result of oil not being able to get out of the big end fast enough.
David
Phil. Irving always maintained that far more harm was done by thick oil not getting where it was needed than by thin oil breaking down when it got there! Heavy oil, when cold, adheres to pipe walls effectively reducing diameter and flow rate.
;-),,John