Vent Plugs?????

[Badger 05]

Okay ladies and gents, I have my first big motor with a SS prop. The motor is a Merc. 150 EFI with a 19p Lazer on it. I have read references to vent plugs on this board and I can identify them on my prop. What I want to know is: What the ##### are they? What function do they serve? I have also read that some people take them out of the prop Why? Is this a performance issue? Any info would be appreciated.

Fishing is: One jerk waiting for another jerk at the end of his line.

[Husky]

If your prop has provisions for vent plugs it will have circular holes under the leadin gedge of each blade, on the barrel of the prop. These holes are about 5/8" in diameter when unplugged. Various sized inserts are available, offering different sized vent holes.
The purpose of the vent holes is to allow ehaust to escape through them at low rpms. This causes the water to have air bubbles in it, which in turn causes the prop to "slip" and the rpms to climb much faster. Motors make more power at higher rpms, therefore more power is available to move the boat when the prop is slipping.
AS the boat speeds up, the exhaust is pulled through the tube of the prop, and no exhaust escapes through the vents. The prop now has optimum "bite" and efficiency to provide power at high speeds.

[Badger 05]

Thanks for the detailed reply Husky! You answered all of my questions. I figured it was a performance thing. I think I will just leave them in.

Fishing is: One jerk waiting for another jerk at the end of his line.