Need Prop ?

[Tleazenby]

I have a 17.7 alumacraft tropy sport with a 1999 yamaha 115 tlry and a ballist tm 19 pitch prop on it. The problem is I have to over trim the engine to lift the boat out of the water then the prop blows out on corners. The engine is in the second hole mount, also on normal trim the engine sprays 2 water line up the back and 3/4 of the boat remains in the water. Do I need a different prop or should the engine be raised. wot I am running 5300 rpm.

 

[Dhadley]

Re: Need Prop ?

Sounds like the motor is mounted too low. The other thing to understand is that the tips of the propeller bades are very important and has a lot to do with how well the prop works. The tips of a Ballistic are cut off. <br />Yamaha makes some decent props as do Stiletto and Turbo. These props will allow you to increase your x dimension and reduce ventalation. <br />Just for fun let me know what true speed you are running and we can calculate slip percentages. <br />Good luck!

 

[Tleazenby]

Re: Need Prop ?

With the engine trim as much as possible wot 5300 rpm and 47 mph. Which the prop will blow out in ruff water or corning.<br /><br />With the engine trimed where it should be wot<br />5100 rpm and 41 mph. <br /><br />I want to be able to have the boat trimed properly have lift and have prop not blow out.

 

[Dunk]

Re: Need Prop ?

Tl, hadley was almost there and should of said Ballistic props flat out stink....He's right the magic in any prop is in the tips. Since the Bal has none, guess what...Fortunately they do hold true to holding down the rpm like other props in the same pitch. They just have no ability to lift the bow of the boat.<br /><br /> Hadley's right again about Stiletto's. They are a nasty high rake bow lifter and they will cure your turning blow out problem. In fact you'll be able to raise your engine a bolt hole or two, probably pick up 1-2 mph. I order a 19" from www.overtons.com Unless Iboats.com has them. I'm trying not to step on toes here???<br /><br /> Stiletto's are great props cheap compared to OEM props....

 

[mbb]

Re: Need Prop ?

The stilletto is a great inexpensive prop. The 90 merc on my boat (no jackplate) has ventilation plate about 4" above bottom of hull. My other merc prop would blow out suddenly when trimming out, I bought 2 stillettos from overtons, tried both (freshwater), used chrome/ss polish to clean the one I didnt want, and returned it for refund. <br /><br />The stilletto tops out 2 mph faster than merc prop, and will not blow out suddenly. I can cavitate it 100 rpm, 200 rpm, as much as I wish. Get one.

 

[Tleazenby]

Re: Need Prop ?

Should I stick with the same pitch (19)?

 

[Tleazenby]

Re: Need Prop ?

What would be a good price for one and what type of thrust washer should I use.where is the best place to buy one. <br /><br />Thanks for your help