Chine walk becoming a pain.

Magnum1500

Seaman Apprentice
Joined
Jan 9, 2006
Messages
33
I'm running a 1992 2.0L 140 hp looper on a 210kg 15ft V-bottom ski race hull. Chine walk is just starting at 50 mph, but I know that if boat was set up better it should do 60 mph +.<br /><br />Engine is on a jack plate with 6" set back off transom. current cav plate is 60mm above bottom of boat.<br /><br />I have installed a water pressure gauge to ensure that I do not jack mtr too much and lose water pressure<br /><br />I am running a 13 3/4" x 23" chopper at 5000 rpm when the chine walk starts<br /><br />I have a steering wing with cables that are reasonably tight, but not piano wire tight.<br /><br />I have added approx 90 lbs up front under deck and this has helped a little.<br /><br />Will jacking the motor up be of help to alleviate Chine walk?
 

Mod2

Senior Chief Petty Officer
Joined
Jun 19, 2003
Messages
713
Re: Chine walk becoming a pain.

Hey Magnum.<br /><br />Sounds like a topic for Prop Questions and Topics. I'm going to move it over there....good knowledgable folks there. Maybe get some help there.<br /><br />Good Luck!
 

javsam

Chief Petty Officer
Joined
Aug 24, 2005
Messages
421
Re: Chine walk becoming a pain.

sounds like you need smart tabs that are sold on Iboats.they will give you more control.<br />javsam
 

Ron G

Commander
Joined
Apr 28, 2005
Messages
2,905
Re: Chine walk becoming a pain.

I think 5000rpm is to low for your motor,how much bow lift are you getting now with the chopper??<br /> Just reread again a 15'boat with a 140 you pushing alot of ponys there,i bet that boat is real light to,you need to keep the bow down a would think to be a little more stable?i got think about this,Kenny and the others will be along to give ya some good advice.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Chine walk becoming a pain.

What kind of hull is it? What design?<br /><br />I ran a 2 liter OMC on a 15' Allison. Ran about 80 in the 1/4 mile at 8200 rpm. That motor on my 15' ski boat ran about 58. That powerhead on an SST 100 tunnel boat ran about 105. Hull shape has a lot to do with it.
 

Magnum1500

Seaman Apprentice
Joined
Jan 9, 2006
Messages
33
Re: Chine walk becoming a pain.

running on a 15ft Magnum 1500. Based on an Australian 1750 bullet design, deep V with a flat pad about 8" wide at the rear. Bare hull is 210kg
 

Magnum1500

Seaman Apprentice
Joined
Jan 9, 2006
Messages
33
Re: Chine walk becoming a pain.

Dhadley, can jacking the motor ease the chine walk or is it likely to make it worse?
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Chine walk becoming a pain.

Many times raising the motor can actually help make it more controlable. <br /><br />I know you have to post the picture somewhere like Photobucket and then copy the url here. I'm severly lacking in that department.....
 

Magnum1500

Seaman Apprentice
Joined
Jan 9, 2006
Messages
33
Re: Chine walk becoming a pain.

Sounds complicated, if you give me your email I can send you some photos
 

LubeDude

Admiral
Joined
Oct 8, 2003
Messages
6,945
Re: Chine walk becoming a pain.

Ive helped several times figure out chinewalking problems on Bass bOats. Sometimes with some hulls its actually imposable to totally eliminate. Raising your engine will indeed help. If you have any slack in your steering or soft motor mounts on the engine, you are fighting an uphill battle.
 

Magnum1500

Seaman Apprentice
Joined
Jan 9, 2006
Messages
33
Re: Chine walk becoming a pain.

OK, will lift engine in 3/4" increments and give it a go.<br /><br />Do sterring cables need to be "piano-wire" tight?
 

LubeDude

Admiral
Joined
Oct 8, 2003
Messages
6,945
Re: Chine walk becoming a pain.

If this is the old style cable type steering, with the springs as part of the connection, you may have to remove the springs. You may have to go to a different more modern steering all together.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Chine walk becoming a pain.

LD, he's using the tunnel boat style cable with wing plates. The problem with that set up is, just as you mention, the slack the cable has when the motor is trimmed. The anchor point for the cable is right in front of the motor and slightly to each side rather than off to each side.
 

LubeDude

Admiral
Joined
Oct 8, 2003
Messages
6,945
Re: Chine walk becoming a pain.

Thanks Dehadly for the explination, I could hardly imagine him still using the old style steering unless he had a death wish!
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,562
Re: Chine walk becoming a pain.

I had a Ranger that would run 50 all day smooth as silk, but bump her up to 55 and you couldn't stay in it (chine walking).....17' Ranger Fisherman with console, 115 Merc tower of power...13x 24 ss Merc prop.<br /><br />Mark
 

Magnum1500

Seaman Apprentice
Joined
Jan 9, 2006
Messages
33
Re: Chine walk becoming a pain.

LD, Dale.<br /><br />I have the fulcrum of the motor pretty well aligned with the shackles that attach to the wing plate. Therfore I get neglible slack appering in the steering cables until the motor is fully tilted like when I tow it to the lake.<br /><br />Cables are not piano wire tight, but pretty firm and if i move the steering wheel 1/8" the motor will also move. the system is pretty tight.
 

brownies

Chief Petty Officer
Joined
Jul 5, 2004
Messages
495
Re: Chine walk becoming a pain.

Dh, Is it possible to have too much jackplate setback? (say for instance 16" on a 17' foot boat).<br /> Not that Magnum has this problem, but, just wondering if too much setback can make one overly squirly.<br /> If so, is there some sort of guidlines for choosing a set-back distance?
 

Jdeagro

iboats.com Partner
Joined
Jul 30, 2003
Messages
1,682
Re: Chine walk becoming a pain.

Smart Tabs will provide many benefits, but I never like to recommend them as a fix for problems that should be cured with proper rigging. In short it is not good to cover up problems. Once you have fixed all of the rigging issues, try Smart Tabs and you will realy be pleased.
 
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