2 AND 4 STROKE PROP QUESTION

[SeaDawg]

Dealers/mechanics, got a question for ya.<br /><br />Do you use the same pitch prop on a 2-stroke as you would for a 4-stroke?<br /><br />Assume that both motors will be going on the same boat, and that both motors are the same horsepower.<br /><br />I think the prop pitch should be the same, but I want to know if anyone has done "on the water" tests to find out for sure.<br /><br />Thanks.

 

[12Footer]

Re: 2 AND 4 STROKE PROP QUESTION

Yes, but only if the RPMs they turn will be the same.

 

[DJ]

Re: 2 AND 4 STROKE PROP QUESTION

Not necessarily. Some 2 and 4 strokes are geared differently. Need to know more specifics. Engine brand, hp, year, etc.

 

[SeaDawg]

Re: 2 AND 4 STROKE PROP QUESTION

djohns19/12 footer, yea, I'm assuming the gear ratios, prop diameters, max rpms, and all that other stuff is the same between the same HP 4-stroke and 2 stroke.<br /><br />Here's why I ask the question. I know that for my boat (Lowe 1760MT), the local dealer props it with a 17 pitch prop with a 50 HP Johnson 2-stroke. His Lowes tech books don't tell him what prop to use with any 50 HP 4-strokes though. I'm thinking that if all things are equal (except the 2 versus 4 stroke), they should have the same prop. <br /><br />Am I looking at this the right way?

 

[12Footer]

Re: 2 AND 4 STROKE PROP QUESTION

Djohns, i meant turns of the screw when I said RPMs. samey-same <br />Yes, you are thinking right,Seadawg.. If the SHAFT rpm is identical,it means everything else is,using the same diameter and pitch.The slip/torque/thrust curves follow the turns of the screw,if the pitch/dia is the same.<br />