prop

[archer379]

i was given a prop today and was told it would work but the numbers don't match. i have a 99 Johnson 70 horse the prop i have on the boat is stamped 13x19. the one i got today is 13.5 x17. What are the difference between the 2 and will it work

 

thanks

[irishfield]

The one you got today is 13.5 inch pitch (theoretically how far forward it would go if you turned it one revolution in a hunk of butter) x 17" diameter.. the one you have is 13 pitch x 19 inch diameter. Put it on and see how it works. I was surprised this summer when Leah smacked a prop.. that a different pitch/diameter combo runs much better on the steel boat than what we had. The marina had two in stock to try.. and the odd ball worked better.

[Fisherman]

The one you got today is 13.5 inch pitch (theoretically how far forward it would go if you turned it one revolution in a hunk of butter) x 17" diameter.. the one you have is 13 pitch x 19 inch diameter. Put it on and see how it works. I was surprised this summer when Leah smacked a prop.. that a different pitch/diameter combo runs much better on the steel boat than what we had. The marina had two in stock to try.. and the odd ball worked better.

And here I always thought the first number was the diameter or...

[irishfield]

Yah,,, you're probably right.. been out in the heat all day ! lol

[skeeter]

IRISHFIELD IS WRONG??????????????

Whats up wit dat??? lol

im marking this one on the calender

 

actually i had the deer in the headlight look when i read that to.

i am in belief that the last number is the inches it should move the boat.

make sure you check the clearance of the new prop when you put it on .

[NANUK]

i was given a prop today and was told it would work but the numbers don't match. i have a 99 Johnson 70 horse the prop i have on the boat is stamped 13x19. the one i got today is 13.5 x17. What are the difference between the 2 and will it work

 

thanks

 

Your old prop was 13" dia x 19 degree pitch, the new prop is 13.5" dia x 17 degree pitch,

as a rule of thumb, for every one degree of less pich you will gain approx 200 RPM, with the new set up you'll probably gain 200/300 RPM (because the new prop has 1/2" larger diameter).

important thing to remember is NOT to acceed recommened engine RPM at WOT,

[archer379]

Your old prop was 13" dia x 19 degree pitch, the new prop is 13.5" dia x 17 degree pitch,

as a rule of thumb, for every one degree of less pich you will gain approx 200 RPM, with the new set up you'll probably gain 200/300 RPM (because the new prop has 1/2" larger diameter).

important thing to remember is NOT to acceed recommened engine RPM at WOT,

 

thanks everyone for there answers. I will try it on the boat in morning then will have to wait a few more weeks until i can get into the water. | guess i better try and fix the tach in the boat lol. I did a quick search last night on the web and was surprized how little info there seemed to be on the subjuct of which prop would work best.