WOT

[WellcraftSportsman23]

I have a 1985 wellcraft sportsman 23 that was repowered with a 2000 merc 5.0 with a bravo one. I am trying to find the correct prop for the boat. Everyone says 4800 at WOT but here is the thing. I have never ran it wide open. Never really tried to push past 3600. I am afraid I will toss a rod or something catastrophic. Oil changed each year and regular maintenance done. Should I just push it and try to get to WOT ? Is there a big difference in straw on the engine between 3600 and 4800?

 

[airshot]

Gotta know the wot rpm in order to make a reasonable recommendation, Otherwise a pure guess

 

[jimmbo]

When the engine is running within the Specified WOT Range, then you know it is corrected Loaded, and has the proper Airflow and Timing Advance Curve from Idle to WOT.
Several Props with different Pitches, Diameters, Rake, Cup, and # of Blades, not even mentioning Brands and/or Models, will likely run within that WOT Rpm range, then you will need to pick the One that most matches your Needs.
Don't be trying to pick a Prop, to give a certain mph at a certain Rpm, as that rarely if ever works out providing the Proper WOT Rpm.

 

[Scott Danforth]

Never really tried to push past 3600. I am afraid I will toss a rod or something catastrophic.

I ran my 2001 5.0 at 5000 RPM for nearly 40 minutes straight often. you are worried about nothing.

as stated above, you need to know you have the proper prop on there. if you load it too much, you lug the motor and kill it. if you are under propped, you are down on performance

assuming your Sportsman 228 is still around 3680# dry, you will be about a 15 x 19p prop (assuming a 1.62:1 drive)

I have a 1985 wellcraft sportsman 23

did you check the transom and stringers? especially round the limber holes. also the cap to hull joint? wellcrafts of the mid 80's had some shoddy work practices just to slap the boat thru the factory

 

[dingbat]

Right or wrong….I’ve always considered red line as the design limit of a motor. WOT as the operational limit of the motor.

Motors are much happier, and under far less strain, when output far exceeds demand.

 

[Scott06]

I have a 1985 wellcraft sportsman 23 that was repowered with a 2000 merc 5.0 with a bravo one. I am trying to find the correct prop for the boat. Everyone says 4800 at WOT but here is the thing. I have never ran it wide open. Never really tried to push past 3600. I am afraid I will toss a rod or something catastrophic. Oil changed each year and regular maintenance done. Should I just push it and try to get to WOT ? Is there a big difference in straw on the engine between 3600 and 4800?

No issue going up to recommended WOT rpm . How long you leave it there is up to you. As others have mentioned I routinely go wot for fairly long spurts, they are designed to take that.

You do want to make sure your prop pitch is correct in that the engine can get up to its wot range. This prevents lugging of the engine through out the power band. You want it peppered so that it can get that high, just don’t have to
Drive it that way all day every day .