Hi John,
Most of the calls over the last week have concerned the oil vent issue. I have written several articles on websites, and in the Whizzer Newsletter about this problem. This problem is fixable and the results will range from 98% to 100%. I have several [many] personal motors with thousands of miles [each] and the only oil I use is during the "oil change" process, not all over my bike & tires.
First I will explain the problem, and then tell you of fixes that don't work, and then my solution.
The problem is two-fold, first the motor produces too much crankcase pressure, and secondly the entire vent system is based on poor engineering. The vintage Whizzer motor didn't have problems with massive crankcase pressure, even when the cylinder, piston or rings were worn. I can assure everyone, as a youth in Ohio, many of my friends Whizzers "smoked", were worn out, and still didn't blow large amounts of oil out the breather. The reason is very simple and easy to understand and you don't have to have a degree in engineering. On the vintage Whizzer motors a deflector plate was installed at the top rear of the motor. This plate stopped the majority of the oil from the rod "dasher" from entering the top rear of the motor, next the American engineers simply mounted an upright tube with a "clapper" valve and filled it with wire mesh, drilled a hole in the case to allow the breather to access the upper rear corner of the motor. Later vintage motors increased the height of the breather to allow the motor to run 8 ounces of oil instead of the original 6 ounces.
When the new company developed the WC-1 motor the vent exit was in the same place, however it was connected to a bunch of very, very, very small passages in, you guessed it, the upper rear corner of the motor. In about the 1st grade I learned if you reduce the size of a passage [water hose] it will develop more pressure [and spray a greater distance]. Worked good for a water hose, but only stops up the crankcase air vent and increases the pressure in the Whizzer motor.
It was somewhat interesting to watch the amount of changes take place in the oil vent system over the last many years. First a line from the motor found its way to the air breather and when the motor built up crankcase pressure it could [and often did] soak the air breather in oil and choke the intake of the carburetor. Next the line was removed from the air breather and found a new fitting attached to the compression cover. The cover later sported another fitting and two hoses now connected the maze of breather & hoses to the side of the motor. The NE motor closed off the hole from the original WC-1 location and drilled a large hole in the bottom of the cylinder inside the tappet area [under the compression release cover]. Now we can really get the oil moving quickly, because the "dasher" on the rod that splashes the oil around the motor is now in perfect alignment with the new hole, and can fill the tappet chamber with oil very fast. The compression cover on the NE motor had a much larger I.D. vent hose and did aid in separating the air & oil, but just couldn't keep up with that rod throwing so much oil via the hole.
There are the facts, here is the solution. Separate the crankcase air from the crankcase oil. Install an upright tube 4.5" to 5", attach to compression cover via a quality hose. If your cover has the smaller fitting, replace them with larger ones [3/8"]. Fill with wire mesh [NOT STEEL WOOL], and the mesh needs to be very porous [I use a pot scrubber from the Dollar store]. Next install a PCV valve in the top of the tube and remember the valve is controlled by gravity]. I installed with a rubber grommet and worked well.
Have fun,
