Posted by Wallywhaler on 07/03/17 - 5:25 AM
#1
Boat: 1984 17ft Montauk
Motor: 2013 115 etec , mounted in the recommended 3rd hole
Prop: 763931 Viper 13 7/8" 19"
Load: 450lbs worth of gear and people, one battery in console, 18 gallons of fuel
Performance(with load above): 5500 rpm, not sure mph haven't had phone gps on with normal load
Best Performance: 5700 rpm 49mph(phone gps) one person 1/3 tank of fuel
Question should I go up to the fourth hole to try to get the rpms to the recommended 5750 with my normal load or am I stuck at 5,500rpms with this expensive prop? Would a 4in set back jack plate or anything other than another prop help?
Posted by Phil T on 07/03/17 - 6:43 AM
#2
As you know, the E-TEC 115 has a WOT range of 5500 - 6000.
Moving the engine up a hole is free and a DIY. I did this with my motor while the boat was on the trailer with the help of a friend using the tongue jack.
I gained 165 rpm.
I would test this change before doing anything.
Adding a jack plate is expensive, adds complexity and encourages the boat to porpoise.
Test and report back.
Edited by Phil T on 07/03/17 - 6:44 AM