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pushing on the nose

Yall pretty smart on here lately! I am inpressed ! Most people will say cant fix that !Its the boats faults ! A lot of people think scientific principle dont apply to thier boat !Old man taught me a long time ago! Push a beer can at the bottom what does it do, it moves ! And then push it about middle way its try to tip and drag ! And my boys rc planes -balance act thier too !Bigger prop- bigger boat ! Rocket science at its best ! You old farts are allright by me ! Balance in life appys to all of us, boats too!i Have put about twenty new thing s to my boat ! from listening to yall thats why its taking so long but well worth it ! It would have took me a lot money and time to get this far with out yall ! I dont have enought wallet to my own thinking thanks guys ! :D
 
Fatboy,
Good to hear from you, i'm no expert but i do know for fact that one of the main ways to stop a boat from plowing and porposeing is engine angle. I've personaly shimmed 3 different boats engines to stop plowing and porposeing and it works. You know a lot of guys want to talk like a rocket scientist and sound smart but things shouldn't be that complicated. I'm like you, my grandad always told me you got two ears for a reason use them. So with that said you can learn alot from your elders if you just listen, they've been there and done that.
 
Hey Chris I have came across this problem a dozen times. If your boat rides on the nose that is the hardest thing to fix. Here are few way's to fix this one, raise the back of the motor up I usually start at a 1/2'' above level, second make sure your rear transom lip is not bent down, put a 1/4 of jack in the rear of the hull behind your gas tank and if none of this works move your motor stand back. I started having this problem since day one with car motor boats and here is why. 90% of all hulls out there are intended for 200 to 300HP aircraft motors with 72'' or shorter props. When you make more horsepower the thrust shoves the nose down also the higher the motor due to the larger diameter props we have to run causes a moment arm and pushes the nose down also. So the more Horsepower or loner the prop the more your boat will ride on the nose. This is one of many reasons I don't run that 80 or 82 prop that everybody keeps telling me is better.
 
just to put in my 2 cents. here on the brazos we put push downs on the botton of motor stand. if it starts to run nose heavy we crank down the push downs about 2 turns if that doesn't help you can turn them down more. it will take some fine tuning once you get the nose running right
 
The funny thing is that I fixed that problem this was on my old fiber glass hull back in Jan of 05'


I got a new hamant aluminum hull and that was the best thing I have ever done. and all the fiber glass guys if they ever tried a hamant hull I found that there is almost no difference in the too I love they way it rides and handles and if I sell it I will defiantly buy another no matter what I'm hooked on the way they ride.
 
I just read this posting today.I have a 15' rivermaster with a 500 cadillac. I have to us a electric trim tab when ever i ride(just me on the boat or four of us). If I do not the boat will start to porpus. I went out and leveled the hall. Then I put the level on th inside of my valve cover. It show that the front of the engine was one inch higher then the rear(prop side). So if i raze the prop side two inches this my take care of the porpusing and make it a little esayer running the hill ???
 
Nope, you want to lower it to stop porpising or move the engine stand toward the front of the boat about inch or two.
 
genevagater,

I wouldn't quite go that drastic right out of the box. I would start in small incriments and work my way up. Another thing you can try ( if your hull is aluminum ) is to slightly bend the overrun of metal that goes past your transome just above the riding surface of the hull. Just to illistrate what I'm saying if you look at the stern of your boat you want to gently bend outward right above where the first transition from bottom to chime is and work upwards about 3-4 inches high. It acts just like a trim tab but you don't have to worry about it when you run dry. I think if you do this along with adjusting engine angle you'll be very suprised but, remeber any time you start altering things it changes how your boat handles.
 
genevagater,

If it will make you feel a little better ask Duckluv26 about doing what i posted above he's my brother-n-law and had a problem with poposing. We adjusted the engine angle and bent the hull with two cresent wrenches and now the boat runs like a sports car.
 
My engine is tilted DOWN at the REAR by about 5 degrees to the STRINGERS. This equates to a little less than an inch lower at the back than at the front.

It doesn't porpoise so far.....
 
When a motor is low in the rear it will ride on the nose (oposite of porposing) and that's what your boat is doing now If you jack the rear up a little you will pick up some speed and your hull will loosen up. Your boat should be majorly plowing on the nose if your that low in the rear, unless you have a Direct Drive. Is it a DD or gearbox, with a motor down an inch in the rear I would guess a DD.
 
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