Harley Davidson Evolution Oil Breather

8 Aug 12 2019.

Harley davidson evolution oil breather. Simply thread into place for a clean looking breather option. Timed breathing was introduced on the. Top breathing engines breath or vent through the top breather bolts which are threaded into the heads of a Harley Davidson motor.

More efficiently by promoting unrestricted breathing. The evolutionâs external filter requires two oil lines. Fast Free shipping and the best customer service.

Hial from ontario canada here. 48 out of 5 stars. The crankcase vented air had to be recycled through the engine.

Heres a drawing depicts the umbrella valves contained within the middle rocker box. Rick since 1994 Harley has used what we call a head breather system in that the crankcase breathers are located in the heads. From breather hose which eliminates engine oil from collecting.

Ive read about this being a problem if they sit but I ride it a few times a week. The design of the oil filter on the shovelhead uses one oil line which feeds the oil back through the filter and into the oil tank. My 96 Softail is puking massive amounts of oil from the breather tube.

HARLEY engines excluding early engines with total loss oil systems manufactured up until 1999 used some form of timed breathing to scavenge oil from the crankcase and deliver it to the vicinity of the return oil pump so that it could be sent back to the oil tank. While running it hard at high exented rpms will add a bit more oil to the breather box you have way way too much. In the following drawing the top arrows are pointing to the oil return oil.