Announcement!

Post by **Redbelly** » September 13th, 2007, 8:03 pm

Redbelly's bote now has a tach and water pressure gauge. They work too.

I thought some of you might get a kick on this info.

Now...is there anywhere on the web that give recommended RPM and water pressures? I don't have a manual.

Post by **birddog** » September 13th, 2007, 8:08 pm

what size motor/paddle?

Post by **Chalk** » September 13th, 2007, 8:15 pm

lies...all lies

what kind of motor?

Post by **Redbelly** » September 13th, 2007, 8:39 pm

Yamahammer 40hp 4 stroking.

Post by **birddog** » September 13th, 2007, 8:41 pm

6000 rpm

Post by **birddog** » September 13th, 2007, 8:42 pm

5600maybe

Post by **Chalk** » September 13th, 2007, 9:05 pm

http://www.yamahapubs.com/html/year_out ... sp?type=OB

Post by **Redbelly** » September 13th, 2007, 9:14 pm

birddog wrote:5600maybe

Mmmmm...I was getting close to 5400 with the motor jacked up maximun and trimmed cause my buddy was forward.

When jacked down to a "normal" height, (the cav plate even with the bottom of the hull), and trimmed for my passenger, I was getting around 4800. This boat has a big tunnel and when lowered there is a good bit of drag on the motor. Don't know if that should affect rpms.
Speed definitely increased with it jacked up to the higher rpms.

I think the prop is a 10x14, 3 blade SS. But I will check for sure tomorrow.

Post by **Redbelly** » September 13th, 2007, 9:18 pm

Water pressure at high rpms jacked up was 20-22. When lowered it was close to 25

Post by **Barhopr** » September 13th, 2007, 9:31 pm

try jacking it up then start trimming the motor up. trim it up till you start to porpose, then bump itdown a notch. As long as you havearound 7-10 lbs of preasure you should be fine. When you trim it out it should feel like the boat just lost 100lbs all at one time. You'll feel it take off. It's called second gear

Post by **mjsigns** » September 13th, 2007, 9:36 pm

Congrats Redbelly

Squall Line · Post by **Squall Line** » September 13th, 2007, 11:05 pm

I have a pretty similar set up on a 17ft g3 tunnel with a Yamaha F60. I get similar readings on wp: 25-27 psi at around 5100 (need to drop pitch on the prop) but I have mine on a fixed jp that is only up about 2" at the moment + the 7" the transom provides over a standard hull.

Post by **Redbelly** » September 14th, 2007, 11:42 am

Barhopr wrote:try jacking it up then start trimming the motor up. trim it up till you start to porpose, then bump itdown a notch. As long as you havearound 7-10 lbs of preasure you should be fine. When you trim it out it should feel like the boat just lost 100lbs all at one time. You'll feel it take off. It's called second gear

I'll try that, but I felt something similar to that when I raised it up and the rpms increased.

I might have to come over next week and me and you run it up the Flint.

I really want a 50hp 2 stroker though.

Post by **Barhopr** » September 14th, 2007, 1:03 pm

Just let me know, always looking for an excuse to get out on the water