1980 Sylvan 18' Sportster Kicker Question

[Alumarine]

You guys were so friendly I thought I'd ask my first question.
I boat in some very remote areas and will definitely need a kicker.
I thought I would look over the winter for a good deal on a 6hp.
Trouble is I don't know if I need a long or short shaft.

Here's a couple of pictures of my transom. Is it possible to tell from the pictures what type of motor I need?
I thought if this was a factory installed bracket someone might have the answer.


The river was really low where we first tried to launch and we got a bit of mud on it.

 

[dozerII]

I'm thinking if you put the kicker mount all the way down then measure from the water line you may get a good idea. But just from looking at the last picture even a short shaft should work.

 

[Watermann]

Man that outdrive is packed with mud. I sure hope you didn't run that outdrive in the mud, it won't take long to ruin the impeller and clog up your whole cooling system.

 

[Georgesalmon]

Get a long (20") shaft, the extra length even if not needed won't hurt anything at the slow speeds your gonna get. Better safe than sorry, if its to short your screwed forever. I went with 25" on my new merc 9.9 pro kicker in case I ever get another boat that needs it, even though I don't need that length now on this boat. It was actually the same price. Actually its nice to have the power head out of the water more in following seas too.

 

[Alumarine]

Man that outdrive is packed with mud. I sure hope you didn't run that outdrive in the mud, it won't take long to ruin the impeller and clog up your whole cooling system.

I was in the boat as we were launching and noticed we were stirring up mud.
We pulled it up and launched 10 feet over and it was better.
Still had to run about 20 feet in the mud.
Have the drive in my basement so I'll see if it had any impact on the impeller. Will replace it anyway.
Motor ran at correct temp.

 

[Alumarine]

Get a long (20") shaft, the extra length even if not needed won't hurt anything at the slow speeds your gonna get. Better safe than sorry, if its to short your screwed forever. I went with 25" on my new merc 9.9 pro kicker in case I ever get another boat that needs it, even though I don't need that length now on this boat. It was actually the same price. Actually its nice to have the power head out of the water more in following seas too.

I think that's a good idea. And as you say then I know it will work.
I'll wait until a long shaft comes up on kijiji.

 

[Alumarine]

I borrowed a 6hp short shaft and was wondering if someone could tell me if it was long enough.
thanks



The board represents the bottom of the port side of the hull.







The yellow line is at the same level as the cavitation plate.

 

[g0nef1sshn]

Im not an expert, but I was think as a kicker and you were to only use it for putzing around and trolling I would think it is fine to use. I think as long as it can cool itself, the typical use and placement of an out board isnt really needed since this will no way get you on plain and have the cavitation issues and porpoising issues.

I could be wrong though.

and maybe you could redo the wood on the kicker mount to fit which ever motor you get correctly?

 

[dozerII]

I think it will be real close, like g0ne said the big question is if it is low enough to get cooling water. By the looks of the ply plate on your kicker bracket you will have to make a new one, any chance you can drill it to mount 2 or 3 inches lower on the brackets to get a little lower.

 

[64osby]

^^^ +1, the motor looks to high.

 

[Alumarine]

Im not an expert, but I was think as a kicker and you were to only use it for putzing around and trolling I would think it is fine to use. I think as long as it can cool itself, the typical use and placement of an out board isnt really needed since this will no way get you on plain and have the cavitation issues and porpoising issues.

I could be wrong though.

and maybe you could redo the wood on the kicker mount to fit which ever motor you get correctly?

Yes, replacing the wooden mount is on my to do list! And I just need it to move me along for emergencies.

 

[Alumarine]

I think it will be real close, like g0ne said the big question is if it is low enough to get cooling water. By the looks of the ply plate on your kicker bracket you will have to make a new one, any chance you can drill it to mount 2 or 3 inches lower on the brackets to get a little lower.

I took a look at it and I should be able to move the mounting board down. Thanks for the idea!
I think I will try a short shaft. I can always sell it if it doesn't work out.

Now I just have to find out what years of older 6-8hp Johnyrudes are good to buy.

 

[laurentide]

Hey Marc, if you don't have the engine yet why don't you just buy a 20" shaft? I run a 20" Honda on a similar bracket on my 18', and it works great. It can be fully lifted and tilted so it doesn't touch the water at speed when running the main OB. And in bigger waves I can still get the impeller submerged more or less constantly. That's my $0.02. Just keep in mind that you can ruin an impeller in only a few seconds if it's out of the water. Cheers.

PS: if you can find a 4 stroke you can plumb it into your fuel supply...but you'd need a sturdier bracket. Cheap 4 strokes are rare but they're out there if you're diligent and quick to respond.

 

[Alumarine]

Hey Marc, if you don't have the engine yet why don't you just buy a 20" shaft? I run a 20" Honda on a similar bracket on my 18', and it works great. It can be fully lifted and tilted so it doesn't touch the water at speed when running the main OB. And in bigger waves I can still get the impeller submerged more or less constantly. That's my $0.02. Just keep in mind that you can ruin an impeller in only a few seconds if it's out of the water. Cheers.

I've been looking and have not been able to find one (at least one I can afford).
It also has to be a 6-8hp as that's about all I can lift easily.

 

[laurentide]

I've been looking and have not been able to find one (at least one I can afford).
It also has to be a 6-8hp as that's about all I can lift easily.

The right bracket will take care of that for you...it'll have beefier springs. I understand not wanting to spend the money, believe me, but if you use it a lot you'll be happier with a 16" travel bracket. That should accommodate a short shaft, too. Just another [albeit more expensive] option. Good luck.

 

[Alumarine]

The right bracket will take care of that for you...it'll have beefier springs. I understand not wanting to spend the money, believe me, but if you use it a lot you'll be happier with a 16" travel bracket. That should accommodate a short shaft, too. Just another [albeit more expensive] option. Good luck.

I meant me being able to carry the motor, not the lift being able to lift it.
This will only be used if my main motor/drive konks out. Not for trolling.

 

[laurentide]

I meant me being able to carry the motor, not the lift being able to lift it.
This will only be used if my main motor/drive konks out. Not for trolling.

Oh, OK, I'd go cheap for that, too. I bet the lower wood mount idea would work for that.

 

[64osby]

You only have to carry it once or twice to get it mounted. After that it just rides along with you.

I have a 7.5 hp that has never had to be used. Every month during warm water season I fire it up and run it. Try to use some of the premix gas so it doesn't go bad. Nice to have it if and when it might be really needed.

 

[Alumarine]

Ok, finally getting around to replacing my crummy kicker bracket.
Picked up a used OMC bracket. It's solid.
Question. Is there any point in putting a 1/2"-3/4" piece of plywood inside the transom as a backing plate.
Would it add any structural rigidity or just more meat for the mounting screws?
thanks
I included a picture because I know it's all about the pictures with you guys

 

[Watermann]

The mount looks good and stout. I think a backer piece would spread the force of the nuts and washers on the inside over a larger area. I would either use strips or a backer plate of AL to keep the nuts from doing that perpetual loosening thing they seem to do with the bouncing weight of a motor when trailering.