1947 knuck oil pump el 61

[andy at wash]

would like to know if is possible to remove and or by pass the governed oil in the pump so that full press is always obtained i have heard this is possible but have not found that person to explain such as of yet thanks in advance

[bmh]

I suppose the factory conversion parts for late 48 to 50 panheads would work just the same , as the pump is the same. Mind if I ask why? I thought the governor was put there to help keep knuckles from puking oil out the top and all over the place. Even seem to remember a shope dope warning against it. If your pressure is too low, I would suggest rebuilding or replacing the pump.
Brian

[Chris Haynes]

If you ever hooked an oil pressure guage to a Hot Knuck you would be terrified at the low pressure they opperate at. Just enough pressure to keep the juices flowing. I was concerened about low pressure back in the '60's and asked the helpful old wrench at my local dealer about it. He said to simply remove the dipstick from my tank and put my finger in pointing towards the return hole. If the finger got hot oil on it the oil was circulating and all is well.

[Jerry Wieland]

Roller bearing motors have virtually no need for oil pressure. That is a babbit engine requirement. Knuckle motors just need some oil flow. Later HD engines only need oil pressure to keep the tappets afloat.

Now back to the original question. You can eliminate the centrifugel bypass by plugging 2 holes - either in the plate or the rotor housing and then throwing the rotor my way. You could also use the 1949 1950 panhead blank plate and unmachined housing but then you would have to remove the locating dowels in your pump.

Jerry

[Rubone]

Jerry, did you get the email I sent you about fender trim types?
Robbie

[Jerry Wieland]

Yeah Robbie I did and I replied but for some reason they must not be going out. That only seems to happen with these board emails. I would like pictures of the trim. I have a bushel basket full of the stuff NOS but it is not labeled. Jerry

[exeric]

Jerry, what was the concept behind the centrifugal pump ? Did it work well, and if it did, why did they do away with it ?

[Jerry Wieland]

HD figured that their bikes were overoiling at speed so they designed that 41 and up pump to dump more oil at higher speeds. The faster that pump spins the higher percentage of oil it dumps back into the sump.

Apparently it did not work very well in dirty mineral oil as was common in the day because they eliminated it in early panhead era. I've known guys who have run the centrifugal set-up happily for years however.

Jerry

[bmh]

I believe the reason for the rotor being eliminated in the first few hundred pans and a kit to convert the ones that already hit the street was that the new hydraulic lifters would collapse at higher speeds. Knucks generally had the opposite problem, At higher speeds oil would be fed to the top end faster then the breather could suck it back to the pump. Turning machine and rider as well into an oily mess.
rian