Author Topic: Predator 212cc Custom valve cover with breather hose  (Read 1697 times)

userix

  • Newbie
  • *
  • Posts: 1
Predator 212cc Custom valve cover with breather hose
« on: December 14, 2015, 02:11:32 AM »
I have a custom short CNC valve cover for my predator 212 cc motorized bike.  The CNC head I have doesn't have any breather hose.  It's a completely sealed valve cover, which I know is bad because there is no way the excess crankcase pressure can escape.  I modified the valve cover by adding a barb hose connector and attaching a breather hose connected to a makeshift oil catch can.

It is necessary to also put a one-way check valve on the breather hose?  I'm not sure if having the crankcase open to the outside atmosphere without a one-way check valve is bad.

smallengineshop

  • Sr. Member
  • ****
  • Posts: 264
Re: Predator 212cc Custom valve cover with breather hose
« Reply #1 on: December 18, 2015, 06:54:07 PM »
You want the crankcase to maintain a slight vacuum or be less than atmospheric pressure. That is why the stock valve cover has the check valve.
John 3:16 For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life.

The Small Engine Shop

Re: Predator 212cc Custom valve cover with breather hose
« Reply #1 on: December 18, 2015, 06:54:07 PM »