Replaced trim anode with "fin" for flat one.

joncrisler

Petty Officer 2nd Class
Joined
Sep 25, 2009
Messages
150
Re: Replaced trim anode with "fin" for flat one.

And I have an 1986 Vette in the garage with less than 90,000 miles driven...and I have never changed the power steering fluid. So what is your point?

Anybody with any understanding of physics, and engineering, could see that a finned tab will only help the PS do it's job. Like I pointed out, if you have never used the fin on a PS equipped setup then you do not know the effect. In your case I would just keep on trucking...!

Happy boating!

I agree with Rocky- if you compared even a PS equiped boat back to back with finned and non-finned anodes (properly adjusted) you would notice the difference. Adjusted properly, a boat with a finnned anode will track straight at cruise speed, while without it there would be a tendancy to turn away to the right.
 

skargo

Banned
Joined
Sep 14, 2008
Messages
4,640
Re: Replaced trim anode with "fin" for flat one.

You guys are going to make me do some testing now.
 

Icyharp

Petty Officer 1st Class
Joined
Apr 27, 2011
Messages
201
Re: Replaced trim anode with "fin" for flat one.

So how come at cruise speeds I can take my hands off the wheel and the boat goes as straight as an arrow? If your theroy is correct I should be pulling the wheel to the left by what you are saying and I am not doing that at all.

Only time I have to correct steering is when I am just putting around but this is nothing new with a V-hull boat, lol a slight turn to the right then a slight turn to the left to go the direction I wish to go......no fin is going to help that.

skargo - do some tests for us, cause I cannot fit a finned one in mine without hitting the prop.......cheers!!!!!!!
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: Replaced trim anode with "fin" for flat one.

This becomes real simple when we apply a little logic;

All single prop out drives have the same prop torque,

Non-power steered setups use the trim tab to offset this,

Power steered setups use the hydraulics to offset this, and this is a 24/7 corrective operation on the PS?s part,

If you use a trim tab to offset the universal prop torque, the hydraulics has that much less to be doing,

And working less, the power steering gets to live a longer life.

Now?most of us don?t even think about this, and ?all is well with the world?.

But?there is no downside, and only an upside, to helping the PS do it?s thankless job with a corrective trim tab. It becomes the discretion of the boat owner as to what he does.

And I am fine with that, really.

Happy boating!
 

cliffblue

Petty Officer 1st Class
Joined
Oct 26, 2010
Messages
209
Re: Replaced trim anode with "fin" for flat one.

My question is.......my mechanic either left my flat one off or left it loose because it's not there now. So, is one or the other necessary?
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: Replaced trim anode with "fin" for flat one.

What out drive do you have?

Before you answer that, the short answer is: all outdrives need the anode for corrosion protection. If you don't have power steering then you need the finned anode to offset the prop torque. If you have power steering then you can go with the flat, or finned, anode...but you have to have one or the other. And we all know by now which one I would use...!

Happy boating!
 

cliffblue

Petty Officer 1st Class
Joined
Oct 26, 2010
Messages
209
Re: Replaced trim anode with "fin" for flat one.

It's a 2001 Mercruiser Alpha One 4.3. Thanks, I'll get another one.
 

skargo

Banned
Joined
Sep 14, 2008
Messages
4,640
Re: Replaced trim anode with "fin" for flat one.

So how come at cruise speeds I can take my hands off the wheel and the boat goes as straight as an arrow? If your theroy is correct I should be pulling the wheel to the left by what you are saying and I am not doing that at all.

Only time I have to correct steering is when I am just putting around but this is nothing new with a V-hull boat, lol a slight turn to the right then a slight turn to the left to go the direction I wish to go......no fin is going to help that.

skargo - do some tests for us, cause I cannot fit a finned one in mine without hitting the prop.......cheers!!!!!!!

Mine does the exact same, it tracks as straight as an arrow!

Looks like the one posted above will not hit a prop.
 

joncrisler

Petty Officer 2nd Class
Joined
Sep 25, 2009
Messages
150
Re: Replaced trim anode with "fin" for flat one.

My Alpha SS with 430 hp 454 required a bit of effort to keep straight- you just hold the steering wheel in the proper place. With a finned anode it could be tuned to run straight with no hands on the wheel. One time I had this anode fall off, and without the anode I could not get up on plane- it creates a turbulence pocket. Obviously how bad an effect depends on lots of factors, but it was really bad on this boat. 454, 1.32 gears, 3200 lbs, very high X-dimension, 23" prop, very low prop slip- it would hit 72 mph on a good day.

Dual prop counter rotating drives (Bravo 3, Blackhawk, Volvo Duoprop) have a flat plate with no fin, for obvious reasons.
 

1stevel

Cadet
Joined
May 20, 2010
Messages
26
Re: Replaced trim anode with "fin" for flat one.

Wow this is good news for me, after reading this post I now know that i can go to a larger prop on my alpha 1 , currently I have a 13.75 diameter and after measuring it looked like I could not go any larger,any one know how large Diameter I can go? I have a 1990 4.3 mercruiser with a Alpha 1? and where do I find one of these off set anodes?
As always......Thanks
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: Replaced trim anode with "fin" for flat one.

Wow this is good news for me, after reading this post I now know that i can go to a larger prop on my alpha 1 , currently I have a 13.75 diameter and after measuring it looked like I could not go any larger,any one know how large Diameter I can go? I have a 1990 4.3 mercruiser with a Alpha 1? and where do I find one of these off set anodes?
As always......Thanks

I'm pretty sure that my Stilleto is 14.25", and I picked up my offset fin at West Marine. The fin can be bought here at iboats:

http://www.iboats.com/Quicksilver-A...9698843--**********.136995238--view_id.166968

Happy boating!
 

1stevel

Cadet
Joined
May 20, 2010
Messages
26
Re: Replaced trim anode with "fin" for flat one.

Thanks for the info Rocky! I glad to know I now have many options,not to many people sell the 13.75, its mostly 14 or 14.25 and so on. I'm happy I found this post.
 
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