Best way to mount a 20” Evinrude 110 on a 25” transom?

[soundchaser]

I have a 1986 20” Evinrude 110hp that I would like to mount on 25” transom. Is there any good ways to do this? I’m figuring the steering cable is going to be a sticking point….

 

[racerone]

Why ??------Find ---bay manufacturing -----for a 5" extension kit.-----Or find a donor motor with the parts.-----Or make a custom bracket.-----Have you heard this motor running ?----How did this motor run for you last season ?

 

[soundchaser]

I actually have a few of these motors, so getting one running properly probably isn’t big deal..

 

[racerone]

There should be no problem in making this work.----Perhaps cut transom down to 21"

 

[soundchaser]

Nice thing is, it’s a boat I picked up very cheap. If I think I can get away with cutting the Transom, I really don’t have problem with that. But I’ll have to see if I can get it bolted up that way. I was actually hoping you guys had a prescribed method you’ve been using. I’ve always kept a collection of old outboards, but it seems to be getting harder and harder to use them……..(

 

[racerone]

I am sure that -----Bay manufacturing -----offers a kit.------Perhaps not within your budget.

 

[soundchaser]

I looked on their site, But I didn’t see the kit #506 I’ll have to give them a call this week.

 

[Texasmark]

What are you doing with it? Gonna bet the 25" transom is on a big water fishing boat of significant size and the 110 is a kicker for trolling. Before you get to concerned about it, go out and run it.

You may be presently surprised that at trolling speeds, fresh water into the prop is adequate since the back of the transom has water against it as high as the boat sits in the water, water that the kicker can develop thrust against and thus moving the boat to get the MPH folks like when trolling! At 4 MPH water will still be against the transom.....at 15-20 not so but you don't troll at 15-20 MPH!

 

[soundchaser]

Na, It's a 1986 Bayliner 1903 CC 19' nice deep V little kick around boat... Has a surprisingly deep V. Seems like it would be fun....

 

[roscoe]

What are you doing with it? Gonna bet the 25" transom is on a big water fishing boat of significant size and the 110 is a kicker for trolling. Before you get to concerned about it, go out and run it.

You may be presently surprised that at trolling speeds, fresh water into the prop is adequate since the back of the transom has water against it as high as the boat sits in the water, water that the kicker can develop thrust against and thus moving the boat to get the MPH folks like when trolling! At 4 MPH water will still be against the transom.....at 15-20 not so but you don't troll at 15-20 MPH!

A 110 hp is likely not a kicker.

 

[roscoe]

I have a 1986 20” Evinrude 110hp that I would like to mount on 25” transom. Is there any good ways to do this? I’m figuring the steering cable is going to be a sticking point….

Setback bracket. Yes, going to need new cable(s).
Between the bracket and correct mounting height, you should be able to get it right.

Bob's Machine Setback Bracket, 4" to 10" setback​

 

[soundchaser]

I was looking at similar adjustable brackets like that on eBay, I like the idea but wonder how well the steering cable will conform to the new motor location? Have you personally had any experience with completing a system of such?

 

[roscoe]

Personal experience has only been with adjustable brackets, as in jack plate.
2 boats, both with plates, 6" setback.

With the setback, you need to raise the engine to position it properly in the water stream. So that will partially remedy the shaft length issue.

On my boats, the steering cable had plenty of room to reach the motor without any tight bends or restrictions.

It depends on where the cable exits YOUR boat, and how restrictive the transom is, and how much lower you need to mount the engine.

 

[Sea Rider]

If you sit a a L20 motor on a 25L transom, the prop will aerate at speed, only good to go boating at reduced throttle on flat calm waters and straight water courses. It's same as mounting an S motor on to an L transom. Don't need to chop the transom down 5 inches, start with 2.5 chop at middle transom.

I know the math doesn't apply but works, been there several times. It's a cheap peanuts cost fix compared to buying an expensive setup brackets. What's the boat's transom material made of : Fiberglass, Alum, Wooden. Post a pic shot rear of transom including a pic of the motor's lower leg shot sideways to have a look....

Happy Boating​

 

[Chris1956]

A Jackplate may work for you. It has to have enough setback for steering and control cables to clear.

 

[Texasmark]

A 110 hp is likely not a kicker.

Ouch!!!!! Little details (I missed....the hp part) make a difference. Sorry about the screwup folks. With that said, I'd agree with Chris. A jackplate could result in some performance besides being a bullet proof way to solve the problem. Cutting down a transom is surely risky business. I have messed with heights on small boats with little fishing engines but nothing like yours.

 

[soundchaser]

No worries, I’m definitely thinking towards a transom plate. I certainly appreciate the help and Ideas, thank you Gentlemen…..)

 

[Texasmark]

No worries, I’m definitely thinking towards a transom plate. I certainly appreciate the help and Ideas, thank you Gentlemen…..)

They make manually adjustable and hydraulically operated, obviously more expensive but situation adaptive. I would think that you could get a manual type, run it, if not happy, undo the bolts, make an adjustment and test, etc. etc. and come up with your best performance.

Obviously that would be a cumbersome process.....test, if not happy, load the boat on the trailer, pull it out of the water, undo the trailer tongue from the tow vehicle, jack up the tongue to get the engine's skeg on the ramp surface, using the tongue jack, jack to the next position on the JP, rebolt, reconnect everything, back down the ramp, run out and test it sort of thing.

Big guns on here say AV plate needs to rise 1" per 6" of setback from the transom. So if your JP is 6" from transom to JP engine mounting plate and you are 5" too deep, you need to have the top of the JP engine mounting bracket 4" below the straight line distance, parallel to the bottom of the boat, from the top of your existing engine mounting height on your transom.

I would bolt my JP such that 4" was the center value of your mounting to the transom. That way you could go up or down to get the sweet spot.

Whether or not this would work I don't know. If I were tasked with this problem this is how I would approach it....having never done it before.

 

[soundchaser]

Wouldn’t I just just put a straight edge out from the bottom of the hull and set the bracket so to make sure the AV is a 1/2” below the top of the straight edge?

 

[racerone]

Carpenters used to say----" measure 2 X and cut once "------So yes you can measure boat and the motor.-----Then determine the steps to take.