Outboard size/Hp vs boat specifications question...

I have a 1971 14' Seaking Jonboat and will be running a 1986 25hp Mariner. I had to replace the transom when I bought the boat. What I did was to glue up 2 layers of 1/2 plywood and add an oak 1"x6" across the transom. I have not had the boat in the water with the 25 yet but I don't think I will have any issues with the transom.

This question comes up a lot.
How much do the other motor weigh? Alot more than a 15? If so, it may be problem. But I imagine they are close.
How wide is the boat? How sturdy is the transom?
I imagine that from a safety stand point, an extra 5 HP wont make much a difference.

However, liability is another question entirely.
If you have an accident with an over-powered boat, then you may be held liable, especially if someone gets hurt. And your insurance may not cover you because you over-powered.
Also, if your state has a law that says you have to be at or below the rated HP on the sticker (Alabama does), then you may get a ticket if you are checked. You will get a ticket if you have an accident the marine police must investigate or they are in the process of writing you up for something else.

I am struggling with this same question, see my post about the Lowe boats. If I get the 1667, I really want to hang a Yamaha 2 stroke 25 on it. But I dont want the liability.

CarlF said:

This question comes up a lot.
How much do the other motor weigh? Alot more than a 15? If so, it may be problem. But I imagine they are close.
How wide is the boat? How sturdy is the transom?
I imagine that from a safety stand point, an extra 5 HP wont make much a difference.

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The answer to the first question is I don't know. I'm still waiting on the guy with the motor to make time for me to see it :x There is also a 1988 Johnson Sea Horse 15 hp long shaft that I looked at (the marine guy wants $600.00 for it). He also has a 1976 9.9 hp Johnson for $450.00. BUT if I can see the motor of Captain Slo' Poke, then I'll know which way to go. I'm not Not digging the idea of raising the height of the transom 5" so I can use the 15hp Long shaft. Anyway, the transom is in fair shape (46" or so across). Although tonite I went to Home Depot & purchased an oak 4'x 1 x 8. I am going to combine (I.e. glue) that with a 3/4' 4' piece of plywood & replace the transom (feel more comfortable with this than what's currently on there). Here's the link to the pics of the boat & transom
https://www.tinboats.net/forum/viewtopic.php?f=13&t=6799

However, liability is another question entirely.
If you have an accident with an over-powered boat, then you may be held liable, especially if someone gets hurt. And your insurance may not cover you because you over-powered.
Also, if your state has a law that says you have to be at or below the rated HP on the sticker (Alabama does), then you may get a ticket if you are checked. You will get a ticket if you have an accident the marine police must investigate or they are in the process of writing you up for something else.
I am struggling with this same question, see my post about the Lowe boats. If I get the 1667, I really want to hang a Yamaha 2 stroke 25 on it. But I dont want the liability.

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I have an answer to that, "uhhhhh what tag, officer? I don't see no tag, it's missing" :lol:
(besides with our beloved :roll: Governor Granholm's hack job, oops I mean budget cuts, I doubt I'll run into too many marine police or whoever especially where I fish. Afterall, I'm not going absurdly overboard with the size-I plan to go with (18-20 hp) is all.

Get teh Dirt Cheap 18-20 hp and just take it easy until you see how the hull handles the engine

Are you sure the old transom is 3/4" thick? Mine was 1". I used gorila glue and a dozen 1 1/2 screws to add the 1x6 oak board. I replaced all 12 of the nuts, washers and bolts with 1/4" stainless steel.

I have heard that certain species of oak does not handle water very well, red oak maybe?
You may be better off with ext. grade plywood than the wrong species of oak.

I'm not sure which oak it was it was in menards damaged boards section. It is on the inside of the transom 1/2 from the top with many coats of paint to protect the wood from contact with the water.

lckstckn2smknbrls said:

Are you sure the old transom is 3/4" thick? Mine was 1". I used gorila glue and a dozen 1 1/2 screws to add the 1x6 oak board. I replaced all 12 of the nuts, washers and bolts with 1/4" stainless steel.

Click to expand...

UPDATE: No, my transom is 1 1/2" thick. It currently has painted plywood (2-3/4" thick) in it's transom. I just took it off & discovered that it was good for 2 things: Jack & squat (& Jack left town). What I am currently doing is combining a 3/4" red oak board 4' long with a 3/4" exterior plywood of the same size. I've glued them together & then I am going to stain & varnish/polyurethane the oak (it'll be the piece you will see when sitting in the boat). I've used stained red oak on boats before (trolling mount brackets) & haven't had a problem with them at all.