Re: What size prop do I need?
You want to prop your motor for the "typical" load you normally carry.
Obviously, it's now propped for the take along a couple of buddies load with the 14 pitch prop.
By yourself, you could likely run a 17 pitch prop(the biggest I see available) and be at about 5600 rpm, with lots more speed.
But that prop probably wouldn't work well with the buddy load, since you seem to dropping about 700 rpm with them along; which might cause you to drop to around 4900 rpm then.
With the range of 4500-5500 rpm, you should still be within the range, but it wouldn't perform as well with the buddy load.
So, you might end up with 2 props(like a lot of us); the higher pitch for lighter loads and the present 14 pitch for when you take the gang along. It only takes a minute to switch out props for the day's requirement.
The motor's hp is rated at 5000 rpm.
Speed readings to go along with the rpm readings are needed to figure slip percentages.
By yourself, with a 17 pitch prop at 5600 rpm, you should see 40ish mph speed.
By the by, the Mercury prop selector indicates that a Tracker type 16ft aluminum bass boat with a
" light " operating weight of about 1285 lbs should turn a 15 pitch Spitfire 4 blade prop at around 5300 rpm @ about 35-36 mph.
This might be a indicator that your tachometer is off. Perhaps you should have the tach checked before doing anything.
50 hp ELPTO 2 stroke. Serial number tag says 5500 max rpms. When the boat is loaded with 2 or more tachs. out full throttle at 5500. When I'm fishing alone tachs out at 6200. I would like to get more top end speed while still maintaining no more rpms than called for. Not looking to blow up motor Would rather buy a new prop.
