1976 85HP Johnson Prop

bowhunter

Recruit
Joined
Apr 20, 2002
Messages
1
We have a 1990 Smoker-Craft 16' Kingtroller with a 17 pitch prop getting 34mph now looking for speed.<br />Thanks Rick<br />RPM 5200-5300 WEIGHT 1400 LOADED ALSO PROP IS SLIGHTLY PITED AND ROLLED AT END OF BLADES
 

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
Joined
May 19, 2001
Messages
26,066
Re: 1976 85HP Johnson Prop

Without knowing your rpm's that is a tough call. You might want to see if you are running in the optimum RPM range. Your trim angle, weight and your engine height all effect speed. Check out the rpms's first. Then post your results with the boat weight here...someone will help you determine a better prop. Then again 34 MPH might be all you can get.<br /><br />Bob
 

Ross J

Lieutenant Junior Grade
Joined
Nov 30, 2001
Messages
1,119
Re: 1976 85HP Johnson Prop

Hi Bowhunter,<br />The book says - 3 blade - 13 1/4" dia - 17" pitch<br />I also have a 16' boat with a Johnson 85hp and you're doing better than I ever have. I go to sea and have some good size waves so haven't played with other props other than a 21" pitch on 13" dia. It gave me a fright with an empty boat. It sent me off the end of the dial which is 30knts on my boat. However when I added any weight it bacame a brick and I went back to the 17".<br />Ross
 
Top