prop selection

[keepiton2]

hi folks,<br />I have a 110 v4 johnson. It's on a 16' stratos f/s. the prop is a 13x19. my ? is: it's slow coming out of the water , but then it's great. I was wondering what prop I would need to get out of the water faster.( wot is 5200rpm.) (42mph). when I have 2 friends in the boat , its almost impossible to get out unless 1 of them moves towards the bow from the back.please let me know as I want a prop for tubing and skiing . Tanks as always folks !!! Skip

 

[steelespike]

Re: prop selection

I dont know what your max rpm should be but at 5200 you are probably in the reccomended range.<br />You could drop down an inch or 2 in pitch.If I <br />remember right 1 inch down will raise rpm 200<br /> and help with hole shot.May lower top speed. Youll need to know your max. rpm and not excede it.Also keep in mind<br />weight distribution and motor trim greatly effect hole shot.<br />Good luck.

 

[sho305]

Re: prop selection

Make sure you trim all the way down to take off.<br />You can try one of those wings on your cav plate, they work good and force more water down to get the boat up. A prop with exhaust vents like a LaserII will help but not knowing if you can pull anybody skiing up with it. If it cavitates, lower the motor or trim more or get a 4 blade; if not then you need more power or less pitch. Move weight forward in boat, and make sure you have good gas, tuneup, clean bottom, etc. Good luck! I would do anything to not loose my speed prop!

 

[Dhadley]

Re: prop selection

You are down on top RPM so it would make sense your holeshot is lacking. Before you spend money on a smaller prop (and lose speed) try raising your motor on the transom (increase X dimension). That should reduce drag and improve your holeshot, top RPM and top speed. Look for 5800 RPM with an average load. Watch your water pressure!<br /><br />Good luck!

 

[keepiton2]

Re: prop selection

tanks folks !! raising the motor sounds so final i would hate to move it , and have the same problem. i quess what i really want is a prop that will allow me to get out of the hole a little easier when i have 3-4 guys in 'er.please lemme know what you guys think ! tanks ..Skip ( p.s. whats the overall difference b/t a 3 and 4 blade prop ?)

 

[MGuckin]

Re: prop selection

OMC like to run around 5800.<br />Actually I think you should be running a 21" pitch, but if you change to that top end would decrease and max rpm would be about 4800.<br />As Dhadley said raise your motor first.<br />He and many others from this board helped me get another 8 mph out of mine just by talking me thru x factor adjustments.

 

[DJ]

Re: prop selection

keepiton2,<br /><br />The others are right. Raising your motor one or two notches will cost you about $6.00 for a tube of 3M 5200 sealant. If you're too low, a prop. is NOT going to help you much.<br /><br />Get your fishing buddies top help you. They're the ones causing you all this grief.

 

[Dhadley]

Re: prop selection

Todays 4 blade props are going to be faster out of the hole and on top end. If you don't have (or plan on having) a jack plate (manual or hydraulic) don't even think about a 4 blade prop. You will not be happy.<br /><br />Good luck!

 

[MGuckin]

Re: prop selection

I didn't bother sealing mine until I was happy with the setting. Leaked a little but no big deal, was just for testing. Bottom bolts were in elongated slots. I just loosened them a few turns. Top bolts had to be removed. Most motors have more than 1 set of mounting holes to work with. I lifted the motor so that the next set of holes lined up and reinstalled them. Tightened everything up and tried it. Took about 15 minutes.<br />Once I was happy with performance, I sealed the bolts.

 

[Spidybot]

Re: prop selection

Look at http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=17;t=013479

 

[MGuckin]

Re: prop selection

UU,<br />Link doesn't work.

 

[Spidybot]

Re: prop selection

Oh, sorry. It used to, but the posts has been reindexed, I think.<br /><br />Search for 'Wisdom of Propellers'.<br /><br />I've put a whole book up on the net, to download for free, about props.

 

[MGuckin]

Re: prop selection

I did not know what the link referred to. I already grabbed that. Great info. Thanks!!!<br />