1992 Johnson prop size

[jc44]

I have a 200hp on a 20ft four winns quest center console which has a prop size 15x17. I think my top rpms
Are around 53 to 5400. I hit somthing the other day and had to take the prop in, the guy at the prop shop thought
The prop was alittle to big. I told him I thought the boat performs good. Planes off decent top speed is aroun 35 to 40
He gave me a prop to try. 14 1/4 x21. It wouldn't even plane the boat off and rpms topped at 4400. Any ideas what a good prop size would be for what I have? Thanks.

 

[Chris1956]

Re: 1992 Johnson prop size

Sounds like you have the right prop. If you go to a 19" pitch the RPMs will drop to 4900-5000, which is a tad low. Goint to a 15" pitch prop will raise the RPMs to 5700-5800, but you may lose speed. The only sure way is to run time trials.

 

[jc44]

Re: 1992 Johnson prop size

Should I go with a lower pitch to get closer to the
6000 rpm range or like you said just stay with the same prop?
Thanks.

 

[jc44]

Re: 1992 Johnson prop size

I think the boat weighs around 2500 to 3000 pounds, if anyone has a similar boat & motor set up and is happy with the prop they are running with please let me know what prop you are using. THANKS.

 

[boobie]

Re: 1992 Johnson prop size

Stay with the orginial prop or go lower on pitch and see what your rpm's are.

 

[jc44]

Re: 1992 Johnson prop size

I just found the original specs for the boat and motor off the four winns site. Their prop specs for this boat and a 200 hp was 14 1/2 x19 pitch. Their top end speed with that prop was 45-49 mph. like you said i would think i would have to go with a lower pitch, what are your thoughts on the 14 1/2 x 19?. Thank you.

 

[Dhadley]

Re: 1992 Johnson prop size

Your "prop guy" thinks a 17 is too big so he suggests a 21?????? Really???

If we were doing this we'd go back to basics and look at set up. Then look at what brand and model 15 x 17 you were using. I'd be willing to bet a good 17 would be fine and maybe - maybe - look at a 19.

 

[jc44]

Re: 1992 Johnson prop size

I think he was talking about the diameter of the prop (15) was to big. The 14 1/4 x 21 he just gave me to try to get thru the weekend. I want to buy a new prop and use the 15 x 17 as a back up. What brand and model do you recommend and going by the specs i just found what do you think about the 14 1/2 x 19 that the manual recommends? I think max rpms for that motor are 5000 to 6000 rpms. THANKS.

 

[jc44]

Re: 1992 Johnson prop size

Thanks

 

[Dhadley]

Re: 1992 Johnson prop size

Not all 17 pitch props are created equal. If we were doing the set up we'd test with a 17 Turbo 1 or Stiletto Advantage 1. Set up is alawys the key.