My 23

[peterb]

Ripndip,

Wow, what a textbook response on how to dial your boat in.

Since I bought some barely used rev 4's (19" pitch) and did not pay too much for them I will give them a shot and let you know how I make out (and will take it from there).

Also, nice swordfish. They are brutes to fight aren't they?

Peter

[Fr. Frank]

Peter B,
I switched the lower units turning the props inboard instead of outboard- if you decide to try this the engine toe will have to be changed from 1/4" toed out (what is normal) to 1/4" toed in to compensate for the pressure the prop direction places on the engine. Your steering tie bar should be adjustable. The theory is the 1/4" of slack is taken up when running making them close to dead straight. If you don't do this, it will be squirrelly.
S

I rigged twin engines on boats from the mid-70's through the mid-90's, and I never rigged counter-rotating engines to rotate inward. Never. In fact, I have only seen this done once in my life, and that was when the 30' Rybo Runner was brought to me to correct it's handling problems after repowering at a different marina.

Left-hand engine rotates left, right-hand engine rotates right. To do the opposite sets up greater lower-unit drag as a result of the confluence of water pressure each motor applies to the other. This is the result of what is called "P" factor, which is the sideways thrust exerted by a rotating pitched propeller. You want to point that thrust away from your submerged running surfaces as much as possible.

Mount the motors on the transom bracket and align the front and back vertical edges of the lower units as measured below the cavitation plate to be 1/4" closer at the front edge than at the back edge with a standard 24" motor separation. This is toe-in. Add 1/4" of inward toe for each 6" of motor separation over 24", as measured at the leading edge of the lower unit below the cavitation plate. The toe-in IS NOT adjusted for distance behind the transom, but motor mounting height IS.

For identical rotation engines, i.e.; both RH rotation, the amount of toe-in is increased slightly. Start with 3/8" to 1/2", and then increase by 1/4" increments.

Because the outer motor in a turn has to travel farther in the turn, regardless of whether your motors or rotating inward or outward, you always must have toe-in, never toe-out, or else you are wasting power by working the engines against each other in every turn.

[3rdday]

Amen brother.

Right on Terry , you tell 'em.
True, Dat! Can I get a witness? Amen, again.
Let's not forget where it started... ?hello? did anyone read the patent? Sorry, just trying to be a funny guy.

[seafari25]

Right on Terry , you tell 'em.
True, Dat! Can I get a witness? Amen, again.
Let's not forget where it started... ?hello? did anyone read the patent? Sorry, just trying to be a funny guy.

K guys I was going to mention that but I thought it went without saying. No disrespect intended but we were on the subject of Potter built.

[ripndip]

Peter B and Fr. Frank,

Thanks on the swordfish, yes that fish (the big one), cost me thousands of after bought gear. It was my second ever, the first was about an hour before that and weighed about 10 lbs. That one took 2 1/2 hours on 80W 80lb test 21lbs of drag.

Fr. Frank you are absolutely correct with the toe-in/out terminology. My apologies. I wasn't thinking about it referencing the front of the boat. Normal outward prop rotation has TOE IN- the lower units are closest at the leading edge. I'm glad you mentioned that before I possibly misled Peter B or someone else.

I will strongly disagree with you on the assumption that almost nobody rotates props in. Go look at any Jupiter, Island Runner, and I think Venture does it too- right from the factory. It is also done quite often on cigarette and other go fast boats. IF you do decide to try it and do not change from (corrected) TOE IN to TOE OUT you will have less than desirable handling characteristics.

As far as it not working, or yielding negative results, I can only say how it works on my setup. If anyone really wants to see and/or feel the difference, I invite you to come for a ride, I'm in North Palm Beach, FL.

PeterB, let me know how the rev 4's do. I'm so pleased with how my boat is running now I've put the props on the back burner and just ordered the new 1K 20 degree tilted transducer. When I put in the first 20 degree ducer, two years ago, Airmar only made it in single element 600W. The new one is three elements, 1K, and substantially larger. The bottom deadrise step of the 23 is almost exactly 20 degrees so I've had good performance with the 600W- 15-1800 ft 2200 once. Can't wait to try the new one.

S

[ripndip]

Here is the big one:

[peterb]

How heavy was the big one? Hope you were wearing a harness.

I like to be macho and all that but that must have been torture (until you got the fish in the boat).

I love the BFT's that we caught up north this year (see below picture of a 130 pound BFT) but i got him on a system 30 after about a 1.5 hour fight (with 13 pounds of drag). But that big sword is in another category IMO.

Peter

[image][/image]

[ripndip]

PeterB,
Rodney did a lot of the work (the rod holder). We estimated 300 lbs. I have another pic of me laying beside him and he is much longer than me stretched out. He was the thickness of my waist at his tail. Nice Tuna. I'm hoping to get into some of those in the coming year.

Skyler

[ripndip]

Fr. Frank,

My apologies again. NOW you can say you have seen them turned in TWICE.




Hope your smiling cause I'm giggling. It was the NEVER that got me.

Skyler

[Islandtrader]

K guys I was going to mention that but I thought it went without saying. No disrespect intended but we were on the subject of Potter built.

A little good nature banter is always fun, don't take it personal.

But don't let it happen again