Set back kit

Joined
Feb 26, 2012
Messages
73
Ok friends, here is what I have. I have a 1967 freeland 16? fiberglass boat. It has a 20? transom. The motor shaft is either 18? or 19 ??. I measured form the top of the mount and also from the top of the transom to get the shaft length. The cavitation (ventation) plate is 2? above the keel. Is this going to be a problem? I am taking it out in the morning and just want to be aware of what to look for. The boat is a trihull. I am hearing that the plate is too high. If so, how do I lower it? Please keep in mind it is a tiller and if I use a setback plate I am going to have a hard time reaching the handle. Thanks for your help. IMG_5248.jpgIMG_5249.jpgIMG_5250.jpg
 

BonairII

Commander
Joined
Jun 7, 2011
Messages
2,727
Re: Please help with cavitation plate

Re: Please help with cavitation plate

You won't know until you test it out. Visually check that the cav plate is just on the surface of the water when your WOT. Also make sure that you are pumping plenty of water cause if your cav plate ends up being a bit too high, your motor will have a tough time ingesting enough water to cool the motor.
 

Philster

Captain
Joined
Sep 15, 2009
Messages
3,344
Re: Please help with cavitation plate

Re: Please help with cavitation plate

Can I be first to say that it's an antiventilation plate? Yay \o/
 

Bondo

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Apr 17, 2002
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70,953
Re: Please help with cavitation plate

Re: Please help with cavitation plate

Ok friends, here is what I have. I have a 1967 freeland 16’ fiberglass boat. It has a 20” transom. The motor shaft is either 18” or 19 ?”. I measured form the top of the mount and also from the top of the transom to get the shaft length. The cavitation (ventation) plate is 2” above the keel. Is this going to be a problem? I am taking it out in the morning and just want to be aware of what to look for. The boat is a trihull. I am hearing that the plate is too high. If so, how do I lower it? Please keep in mind it is a tiller and if I use a setback plate I am going to have a hard time reaching the handle. Thanks for your help.

Ayuh,.... Welcome Aboard,... You've got the Wrong motor for that hull....

It ain't gonna work very well,....

That motor goes on a 15" transom,....

From the 1st picture, it appears 'bout 1/2 the prop is gonna be cuttin' Air.....
Can't tell ating from the other 2,... bad angles...
 
Joined
Feb 26, 2012
Messages
73
Re: Please help with cavitation plate

Re: Please help with cavitation plate

ok, did not work very well. Need to figure out how to make this motor work on this boat. Set back Kit?
 
Joined
Feb 26, 2012
Messages
73
Set back kit

I am using a short shaft on a 20" transom. Needless to say it does not work very well. I am limited on funds and need to figure out how the get the motor lower. setback kit sound about right, i think. Any help would be very appreciated.IMG_5250.jpg
 

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
Joined
May 19, 2001
Messages
26,046
Re: Set back kit

Well you could build one with some aluminum angle and some plywood......... but......... it will also move the steering away and you might not be able to have full control over turning.

You might not like this response but........... sell the motor and go for a longer shaft OR you could modify the transom itself which people have done and trim a few inches from the top near the motor mount.
 
Joined
Feb 26, 2012
Messages
73
Re: Set back kit

Bob_VT I thought about both. my worry is if i use a set back how far back do i need to go in order to turn. i have already made a handle extension for the steering. Also, i wanted to cut the transom down, but many people say it is not a good idea.
 

Bob_VT

Moderator & Unofficial iBoats Historian
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May 19, 2001
Messages
26,046
Re: Set back kit

Depends on the hull, type of boat, budget....... and what is available if you decide to cut it down. I added 2" in lift to my 14' boat since it was originally made for a short shaft.

You will have to "engineer" the amount of clearance you need if you decide to make a set back. Since it is a small light motor .....they are not hard to make
 
Joined
Feb 26, 2012
Messages
73
Re: Set back kit

Make sense. I would really hate to sell this motor. We have a history and i trust it. Just trying to get a good feel for what i should do. I have looked into shaft extension kit for the motor, but had no luck. I think I will see what I can do with a set back kit.
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: Set back kit

Go to the salvage yard list in the Top Secret File. You should be able to find a 20" leg or an extension kit there unless you have some off brand outboard.

Whether you trade outboards or modify the one you have or trade boats your best bet is an outboard that fits your boat. A setback for a tiller outboard is guaranteed misery and simply won't work with a remote.
 

BonairII

Commander
Joined
Jun 7, 2011
Messages
2,727
Re: Set back kit

I'm for cutting the transom down a couple inches. Costs nothing and will solve the problem.
 

mwassman

Seaman Apprentice
Joined
Jan 13, 2011
Messages
46
Re: Please help with cavitation plate

Re: Please help with cavitation plate

Look into getting yourself a adjustable jack plate. You have a 20" transom with a short shaft motor, your cavitation plate should be almost even with the bottom of the hull and you cant do this with standard mounting methods. A adjustable jack plate will alow you to lower your motor to the hight that you boat runs best at. I picked up up at bass pro that you can adjust with a wrench, these are alot cheaper than hydraulick jack plate. It will run you around $240 and wiegh about 25lbs
 

MWG2600

Petty Officer 2nd Class
Joined
Sep 4, 2011
Messages
157
Re: Please help with cavitation plate

Re: Please help with cavitation plate

You need an extension, goes between the midsection and lower unit.
 

5150abf

Vice Admiral
Joined
Aug 12, 2007
Messages
5,808
Re: Set back kit

Cut it down, you know that will work and it cost next to nothing to do, the setback will be an expense and might work, all you need is probably a 2'' drop in the middle 14'' or so wide, if you got a nice radious on it no one would even know you did it.

With an extension you need to disassemble the lower to get the longer shaft in adn all kinds of stuff can go wrong there, teh cut down the is the easiest least expensive most likely to work solution.
 

mwassman

Seaman Apprentice
Joined
Jan 13, 2011
Messages
46
Re: Please help with cavitation plate

Re: Please help with cavitation plate

for got to mention i also had a short shaft tiller on tall transom , you wouldnt have to lower it much. But deff try it out before you do anything. By the photos i think it would be fine. A a shaft extension would be a great fix, although getting lower units off older motors can be tough work expecially if it was used in salt water, i sold my 83 evinrude 35 hp that needed foot work because i couldnt get mine off i was told that certain parts will carrode together and sometimes you need some heat to get them off, that was just my situation though
 
Joined
Feb 26, 2012
Messages
73
Re: Please help with cavitation plate

Re: Please help with cavitation plate

Ok, I am going to go to a fiberglass boat shop and see about having them cut it down and make it look pretty again.
 

Home Cookin'

Fleet Admiral
Joined
May 26, 2009
Messages
9,715
Re: Please help with cavitation plate

Re: Please help with cavitation plate

If you cut down the transom you may have steering conflicts and it may be hard to tiller steer when it's lower. Plus you compromise safety with the lower transom--you'll catch water over the stern. You may end up with a boat you can't use.

I think you are going through a lot of risk and expense over a $400 motor--and one that would be easy to sell or trade. Getting the right motor is the only thing that makes sense in my view, even keeping the tight budget in mind.
 
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