Was talking to a site member about my set up....
Gottake 175. 2 stk and at wot I get 4900 rpms
At 53 mph with trim way up and almost bouncing......he suggested going down to a 24...
Your thoughts please. Will I get more speed and more rpms?
Was talking to a site member about my set up....
Gottake 175. 2 stk and at wot I get 4900 rpms
At 53 mph with trim way up and almost bouncing......he suggested going down to a 24...
Your thoughts please. Will I get more speed and more rpms?
If your motor is running properly then it does sound like you are over pitched. On that rig...should be about a 250-300 rpm difference for each inch change in pitch. A 24 should put at around 5400-5500 rpm's which is good. Would also get you out of the hole better, drive better and get rid of that porpoising issue too. Speed should remain the same...may even get another 1-2 mph out of it. I agree with the member who advised you. 5500-5700 is an acceptable operating range at full throttle so a 23 might be in play too.
96 Bullet 20cc, Yamaha OX 250+, 10" jack, labbed 30" Bravo LH w/1.25" exhaust pipes, counter rotating Bob's lower, it goes faster when you spin it the other way...
Well you didn't say what 175 hp motor but either a mercury or an OMC should be running a 24" prop turning 5500-5700 rpm's and 63-64 mph. That 26" prop is too much pitch for a 175 and it needs some work.
Johnson...sorry
24" raker is what you need and a 6" jack plate if you don't have one. You have to have the plate to get any real speed change on your boat.
Not doing a jack plate....not spending that money.
If you get lucky you can find a used manual jack on Craigslist or ebay and basically steal it price wise. It will be a big help with the porpoising, not to mention about 5+ more mph instantly. That 6" is a popular size here with all the bay boats and they do show up for really good used prices.
96 Bullet 20cc, Yamaha OX 250+, 10" jack, labbed 30" Bravo LH w/1.25" exhaust pipes, counter rotating Bob's lower, it goes faster when you spin it the other way...
You can buy a new Vance 6" plate for $200
the proposing came from me being a full trim i left it there to tweak it in but i brought it down a notch and it ran flat.
just didn't get the range i needed . may go down to a 24. but my guess is that they put on a 26 and so they don't go over max on the rpm's. i was getting 4900 @ 53/54 on gps.
Running that motor at 4900 will do more damage to it than running it 5500. That boat with a 150 on it and a 24" prop ran more than 60.
wow....i gotta get a 24 next year......got a few more times on the water this year and then
rap it up for the year.....i'll keep that in mind. so a 24 should be a big improvement?
you know ....i keep seeing post with motors a bit smaller(150 0r so) then mine hitting 60 plus and
i was wondering why i didn't even come close to those numbers.
i saw this on line and it calls a min of 5000.....i believe. what I'd like to know is
what prop came with this motor originally . saltwater motor??
1992 Johnson 175 HP
J175GLEN Fast Strike
This 175 horsepower Johnson outboard, manufactured in 1992, is a saltwater model. The engine weight is recorded at 370 lbs. This is a 6 cylinder model. The displacement for the pistons is 158. The bore for this outboard is 3.6 inches and the stroke is 2.58 inches. This engine has power steering and a electric-type starter.
Serial Number: EN
RPM Information: 5000
Your engine's RPM range is important in choosing the right propeller for a given application. For example, if you look at your tachometer at top speed and it is not within the engine's RPM range then that is generally not good. You want your RPM's to be within the proper range while at wide open throttle (WOT). Be sure to do your testing under your normal boating conditions and with a good propeller (not bent, cracked, or excessively chipped).
Information on this page is provided to you as a free service of iboats.com. Because this information has come from many sources we can not guarantee its accuracy. Even if this information is the same as the original factory specs, boats are sometimes modified. Thus, for safety and other reasons, it is a good idea to verify information here to make sure it matches up with your boat.
Last edited by tav; 10-24-2017 at 08:00 AM.
Props are not motor specific, they are application specific.
ok thanks
I think you'd be better off with a jack plate. You'll never get max performance without it and even a new plate is cheaper than a prop. I think you want to run closer to 5500 than to 5000.
Last edited by d'Wayne; 10-24-2017 at 10:15 AM.
I'm only looking for another 500 + rpms and dropping to a 24 will give me 250 rpms per pitch drop .... am I some what right?
Right...Originally Posted by Bullet 20cc
96 Bullet 20cc, Yamaha OX 250+, 10" jack, labbed 30" Bravo LH w/1.25" exhaust pipes, counter rotating Bob's lower, it goes faster when you spin it the other way...
I have a 6" manual off of my xpress that you can have for $75. CJ
2002 X19 200HP OX66 HO Vmax,HPDI lower, it lives, thanks Hydro Tec.
200 rpm's per inch gain in rpm's. My guess is they put that 26" prop on there to sell a boat not gain anything. Ocean Pro motors will turn 5500 rpm's too, but I'd bet your running wrong prop to pad anyway. Which blot hole are the bolts in that hold the motor on the transom? That propoising comes from the prop not being able to carry the bow and it drops then grabs and picks it back up then repeats.
I did check it and it's about 3 1/2" b/low pad
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