Bracket mounting question

[John R]

23 SC - When mounting a bracket on an existing top condition 25" transom, does the raised lip of the bracket allow you to compensate for a 30" engine? In other words, can you mount the bracket high, say just below the notch? and with the added height of the lip over the bracket effectively rasing the height and allowing for a 30" shaft engine? Did I word my question right?

...and speaking of , anyone hear from LT lately?

[Scott]

Hmmm....John when you say the "Lip" do you mean the engine mount on the bracket??

Dont forget the rate of rise (water coming off the bottom of the boat) will also effect the height equation here. The engine on a bracket with a setback of 24-29 inches already will need to be mounted about 2- 4" higher than its equivalent mounted on the transom. A Float bracket built for a 25" shaft could be moved up the transom higher but then you lose the effects of floatation chamber. Don’t forget that many float brackets used the transom to seal the bracket so you could not go above the notch anyway.

Is there a reason why you would not close the transom??
Maybe I misread your question.....

[ April 16, 2003, 01:27 AM: Message edited by: Scott ]

[JohnS]

John,
I understood your question but, man, you used a lot of words and I had to think about it for a minute. Good job!!!!

No, you will not use a 30" motor! Simple answer.
If you are going to use a bracket, you really should consider closing in the transom. Just makes sense......

John

[Briguy]

John R,

The math that goes into such a calculation is not so easy. Theoreticaly for your motor, you need to mount it at 30", then subtract 4" for the "lip" as you call it. Then add back 2" because water rises 1 inch for every foot of setback. The final number is 28 inches. You cannot mount a bracket designed for 25 inches 3 inches too high. However you have 2 clear and workable solutions. Number one, you can have the "lip" of the bracket custom made about 5 inches higher. The second solution would be to simply buy a manual jackplate. They cost about $125.00. I have seen this done on a seacraft with twins with a guy who mounted his bracket too low. It worked out great and allows for easy final adjustment. Hopefully I can test my motor/bracket combo this weekend and let everyone know how it performs.

[John R]

Thanks! I guess I need to know the formulas [img]images/icons/smile.gif[/img] .

Reason why I was asking is that if I went with a bracket on my existing nice shape 25 notch, I would rather not redo a perfectly good transom just to have one big piece to close it off. I would fill in the rest of the notch (and do something creative like a transom livewell) but mainly not needing to redo the entire transom.

I am insterested in how to figure it out. And no real need for a 30" motor - I was just locked in to notch thinking...

Thanks....

Grind & Giggles - any good recommendations for that manual jack plate? and there are no penalties for that? Someone mentioned that there was potentially problems...

[Jpilot]

You will be sorry if you do not close in the transom. It will really finish the boat off if you do. I made that mistake already, and am now closing mine off.

[John R]

Oh, if I bracket, I completely intend to close it off - just not redoing the whole transom. I would close it off with a live well it just would not be a major load bearing piece like the existing transom - make sense? I swear I'm losing my english with this crappy weather - hit 80 yesterday but won't break 40 today...

[other tom]

Your bracket will be custom made anyways, and yes, they can build it to accomodate a 30" shaft engine. You want the bracket mounted as low as possible to get the most flotation though so it will look a bit odd. Jackplate by CNC will do the trick. Are you stuck with a 30" shaft motor? It sounds like you have a 25" transom now...

[John R]

Part was just ignorance on my end (that's why I'm asking [img]images/icons/grin.gif[/img] )... Right now I have a 25" notch with twin 20" engines that I will sell (hopefully) soon. I'm also not 100% certain if I would get a bracket or not and was asking to weigh that against a 30" motor and some kind of smaller buildup of the transom...

I'm floating a couple ideas at the moment...

One of which is: If while I'm waiting to sell the 20 inch motors and decide to run just one of them, is there a Jacl Plate that can be used to mount an engine down? Or will steering and controls, and tilt prevent that from working?

Thanks....

[SECF3114M73J]

John, years ago when most outboards had 20" shafts (this was mid 70's when V6 O/B just came out)prior to this most 23's had twins(mine had twin 65 hp. mercs. talk about a dog!)A local guy put a 20" motor on his 23 fter. I think he had to cut a deeper transom notch.His motor was half submerged a good bit of the time. It's not a good idea unless you plan to rig a snorkel for the motor.