25hp Johnson Propeller help

Hello, I did some searching and needed some help deciding on a propeller for my specific situation.

I have a 15ft aluminum Jon boat(1985 Fisher Hawk 1542 I believe) with a casting deck like a bass boat and storage. Don't know exact weight but it has a 25hp Johnson with a mini jacker plate because its a long shaft motor. Current propeller is an aluminum 10.5 x 11 and works great but I would like to increase my top speed. I took a tachometer and with me by myself top speed is about 21mph and the engine revs out at about 5800rpm. If I add another person I can still get about the same top speed and the boat jumps on plane fairly quickly. If I have a third person it takes a little longer but planes out and still gets up to about 18-20mph but I haven't tested the rpms with 3 people on it but feels like it is still in the 5k range maybe. My goal is to raise the top speed with me on it I think this thing has some more room for pitch but wanted to see if anybody has any experience with a setup like this.

Here are some options from Solas aluminum 3 blade all about the same price of $60-70 online:
10.3 x 12 2211-103-12
10.1 x 13 2211-101-13
10.0 x 14 2211-100-14

Here are options for the Turning Point Propeller Aluminum 3 blade (hub is separate)
Hub Kit 11200200 $30+/-
10.125 x 13 21201310 $60+/-

What do Yall think? I would like to get up to 26 to 28mph

after6tuning said:

What do Yall think? I would like to get up to 26 to 28mph

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1st - I'd never buy a Solas prop ... good watercraft impellers yes, but I've never seen one of their props as a best performing prop - ever. The T-Point pressed aluminum Hustler brand are amazing, especially the 4-blades.

2nd - Did you run your rig through the prop calculator by T-Point as posted on the motor forums?

3rd - Fhugghedabout speed as your primary goal ... you need the most RPMs you can get for that rated OB motor, so if a 6,000 RPM max motor, pitch it so it is 100 to no more than 200 RPMs off (you, standard gear always carried & ~1/3rd fuel; ideally not tested in hot weather). I always pitch to be <= 100 RPMs off. To do anything less can cause lugging of the OB motor, as boats only get heavier with use and as the season progresses.

Yes, I admit I have my biases, but whatever, it is what it is ...

I did run my information through the Turning Point calculator and it gives me only two options: another prop like the one I have or the one I listed above. Solas seems to have more variations. What's interesting is Turning point has a YouTube video of identical boats going from a stop and accelerating to full speed and of course they use a competitors prop on the one boat against their own brand on the other and the only competitor who was able to keep up was the Solas prop. I imagine the one I have is the factory one and probably the same quality but who knows. I will still keep my current prop for when I take multiple people out but for when I fish alone and go down the river and get passed by a pontoon it is frustrating.

I feel that If I have either one or two people on the boat and the rpms max out and get the same top speed I should have some room for more pitch to gain a few mph.

As I was reading through the forum I noticed a post regarding the rule of thumb for every degree of pitch you lose or gain "x" amount of RPMs But someone commended that It apply to under 50hp.

I ran one of those turning point 4-blade pressed aluminum Hustlers props on my 60hp OMC on my 16‘ StarCraft, turned almost 6K w/ me, all gear & 3rd fuel. Ran @ 5,900 w/ 2 aboard at identical load. Once had 6 aboard and it’s still turned up to 5,700 RPMs, keeping the way to the stern; boats love it when the weight is in the stern with a heavy load. At least with a 4-blade prop, as she’ll carry a load.

But yes, now maybe I could’ve tweaked a few more MPH out of it with a 3-blade, but that 4-blade turned out to be a “one prop does all” proposition for me! With turning point, did you check off the box to have them email you and discuss the results? Or call them, as their customer support is fantastic! Good luck, [insert ‘thumbs up’ icon].

I have a 16’ Crestliner MV, riveted boat, maybe a little over 300#. My motor is a 25 Hp Mercury 2 stroke. I use the turning point 13 pitch for average loads— two big guys, trolling motor, battery etc. it pops up nicely and tops out at about 24 mph. I use the 11 pitch turning point prop for heavy loads, a third person etc, tops out at about 21. I like that the hub for the Turning Points is a one time purchase and swaps easily between props. I have some experience with Solas props. It was a mixed bag for me. I had a couple three blades that worked just fine and a four blade that was a dog and out of balance.
From the experience you described, I think you’d get good results with the 13 pitch. I bet you’ll go faster than you are now. Whether you hit the speed your looking for depends on a lot of factors. I think 13 pitch is a factory standard for your motor, it is for my 25hp. As for running a 14, you’d have to have a really fast, lite setup to take advantage of that.


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assuming your 25hp johnson is a twin cylinder, the max rpm is, off of memory, 5500. If you are already at 5800, your are under-propped and increasing pitch by one inch from what you currently have "should" get you in the ballpark, propbably pick up a couple mph as well. If yours is a 3 cylinder, max is 5800 as I recall and if you're at 5800 now, I'd say that's just nearly perfect. Ideally you want to be at the upper limit of maximum rpm for best all around performance.

I think it try the 13...
You say you have a mini jacker because of wrong length motor, is your cavitation plate at least level with the bottom of your boat, much spray when WOT?



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Ok, wait a digidy-dang moment with all this trash talk about Solas props. I'm running 10-1/8" X 13 Solas on the same engine (short shaft). 5400 RPMS, 28.5 MPH, 14'-boat, 1-person, 1" shim under clamp, 2nd trim hole out. Turning Point, Power Tech, etc, I don't see how paying twice the cost can justify much more gain. I've gotten a wealth of info from this site regarding correct mounting. For best performance and the basis for any prop evaluation; the ventilation plate needs to be out of the wash and fully visible at WOT.

turbotodd said:

assuming your 25hp johnson is a twin cylinder, the max rpm is, off of memory, 5500. If you are already at 5800, your are under-propped and increasing pitch by one inch from what you currently have "should" get you in the ballpark, propbably pick up a couple mph as well. If yours is a 3 cylinder, max is 5800 as I recall and if you're at 5800 now, I'd say that's just nearly perfect. Ideally you want to be at the upper limit of maximum rpm for best all around performance.

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Operating range upper limit is 5500, not the rev limit.

OP, look on your power pack. If it has 5800 on it you are limited to 5800rpm and should go up one size on your prop.

If it does not have 5800 on it it is not rev limited, but you should/could still go up one prop size.

Ok. So I picked up a turning point propeller and hub kit with the 13 pitch (was available at a somewhat local West Marine) and now i do 26mph and seems my reverse works better. I think my turning is better to but maybe thats just in my head. My motor still sits too low in the water and I get a lot of spray from the back while going fast. I am keeping an eye out for an adjustable jack plate so I can raise the motor a bit more. I think I can get 28-30 with proper trimming. I like going on the st johns River and just hate going 20mph and having a pontoon pass me, haha.

I would say that you were hitting the rev limiter before and now your more in the power band.

Realistically, until you get your motor height worked out you cant really tell what your working with.