I have read 4 stroke pumps are slightly different than 2 stroke pumps. 4 stroke pumps have that screen/filter thingy to keep crankcase oil from filling up the pulse line. The pump on a 4 stroke should be mounted higher than the motor fitting and pitched back so the pulse line can drain. That filter thingy will allow air in so the crank oil can drain back….what the article said…
crosbyman Canada Member - 2 Years Replies: 2717 Topics: 269
interesting… but does not explain why so much fuel oil is pushed into the B&S pump from the pulse nipple…
I wonder what would happen if a check valve was in line with the pulse line to allow vacum only to reach the B&S pump with fuel oil being stopped from progressing to the pump … the check valve acting like a reed valve.
wonder if they make ” vacum impulse only” pumps…. that should solve all these fuel conversion issues on the CDs .
The 4 stroke version of the Mikuni rectangle pump has a very small hole that serves the same function but the pulse line must be pitched back towards the pulse fitting.,.