Determining leg length, strange heeling issue...

Boat_Boy!

Seaman Apprentice
Joined
Jul 29, 2001
Messages
34
I have an aluminum cutty, that exhibits a weird "pull" to starboard near top end of the throttle. At high speeds, the starboard aft corner seems to pulled or rather the port aft corner is pushed requiring significant ourse corrections at the helm. The boat is flat bottomed at the aft with a 18 degreee V at the bow. No chines to speak ofm, just the standard aluminum vanes.<br /><br />This problem makes the boat undrivable at top speeds, and heaven forbid one hits a broadside wake off another boat. I nearly flipped the whole thing last week.<br /><br />Could this be a leg length issue? Prop selection? How does one determine the correct leg length for a boat? I am rebuilding the boat this winter and could concievably raise the transom height.<br /><br />Thanks!
 

12Footer

Fleet Admiral
Joined
Mar 25, 2001
Messages
8,217
Re: Determining leg length, strange heeling issue...

You runnin twins? I've heard of chine walking, but man! in a CC? If you only have the one outdrive, first make sure it is tight on the transom, then check the skeg and the zinc (if so equipped) to make sure they are lined-up.
 

Boat_Boy!

Seaman Apprentice
Joined
Jul 29, 2001
Messages
34
Re: Determining leg length, strange heeling issue...

No, I'm not running twins, just a single Yammy C40. I think the leg is too long, could that cause the problem?
 

kev_79

Petty Officer 1st Class
Joined
Aug 5, 2001
Messages
355
Re: Determining leg length, strange heeling issue...

your cavitation plate should generally be +-1 inch from the bottom of the transom. My boat displays similar problems, but only when I've got a bunch of people, and the weight if off centered. Could weight distribution be a factor? Good luck
 

Boat_Boy!

Seaman Apprentice
Joined
Jul 29, 2001
Messages
34
Re: Determining leg length, strange heeling issue...

I have messed around with moving the tanks forward, putting the battery on the port side to even out my weight as I drive, and it seems to make little difference. The effect is worse when I have more mass in the boat.
 

Cedarplug

Cadet
Joined
Oct 8, 2001
Messages
13
Re: Determining leg length, strange heeling issue...

I have a 20'Bayrunner. With the factory 3 blade aluminum prop. she pulles hard at top speed. With a 4 blade comp. prop it does'nt pull at all ( the comp. prop is less dia. than the other prop.).
 
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