question about recirc hoses

[vranasaurus]

The motor is an 1989 90 HP evinrude.<br /><br />I was examining the motor and discovered that one of the check valves was broken and the recirc hose was not attached. (Check valve on intake manifold to bypass cover.)<br /><br />How critical are these recirc hoses and check valves to proper engine operation?<br /><br />I have a new one on order. But will this affect engine operation at high RPM's?

 

[R.Johnson]

Re: question about recirc hoses

They scavenge excess fuel from the crankcase, and direct it to the intake port. This makes for a smoother idle for one thing. A broken valve, or hose would cause an air leak.