A Transom Question & a question about OB Trolling brackets?

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BloodStone

BloodStone

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1) I have a transom mounted, adjustable, stainless steel trolling bracket in very good condition & it is rated for up to a 20hp OB motor. Now does that mean said bracket can only hold the WEIGHT of a 20hp OB motor or the FULL THRUST of a 20hp OB motor wide open? The reason I ask is because the boat I am currently working on has one of these brackets mounted smack dab in the middle of the transom (boat is an 11ft Carolina Skiff looking boat with side counsel). The motor I purchased for the boat is a 1987 Mercury 25 hp short shaft. The transom on the boat is 20" deep & it appears that at high speeds the motor will not get an efficient amount of water. Which leads me to question #2); Since it appears I am only 2" or so short & the transom length is 6" (measured inside from the backwash guard on up), can I cut a 2.5" x 10" piece out of the transom without weakening it terribly in order to drop the motor down to an efficient water level? I only need 3" total for the motor to clamp on.

* I don't want to get another motor or boat etc..& I've already inquired about making it a long shaft & it's a headache in the waiting most say. Thanks in advance.
 
I've personally never found those brackets to be all that sturdy. I certainly wouldn't trailer with a 20 hp motor on one. I'm betting they would be alright on their intended use (sail boats, which aren't trailer, nor subject to planing speeds in somewhat rough water), but I personally wouldn't want one on a real boat.
 
bassboy1 said:
I've personally never found those brackets to be all that sturdy. I certainly wouldn't trailer with a 20 hp motor on one. I'm betting they would be alright on their intended use (sail boats, which aren't trailer, nor subject to planing speeds in somewhat rough water), but I personally wouldn't want one on a real boat.
Click to expand...

Hey BB; :beer:
I am not worried about trailering because I have one of those transom savers. It's using it on the water with said bracket that I am concerned about (I won't be out on rough water with it & definitely not at high speeds). So are those brackets rated by weight of the OB or the actual torque of the motor itself? What about the transom issue; is cutting it a little like I mentioned earlier advisable?
 
I would make some sort of jack plate to lower the motor before I'd go cutting on the transom. also those Aux motor brackets are made for trolling applications, IE; slow speeds.
 
No way would I use an auxiliary mount for anything other than trolling speeds. I tried it with a Nissan 9.9 and just about killed myself. If it built like a Carolina Skiff you can cut the transom down and be done with it. However, if it is remote steer (side console) I would put a jack plate on it and call it done. No permanent mods to the boat, easy on and off, will allow you to get the perfect depth for the motor and they are SOLID.
 
Crankworm said:
Is this the type you are talking about?

https://www.cabelas.com/cabelas/en/...arentType=index&parentId=cat420001&id=0000921

My dad had one on mounted on a sea ray with a 15 horse kicker hanging on it, we never had a problem trailering or banging through the waves.
Click to expand...

Yes, just like that (2nd one to the right at the top). Did you ever have to open the 15hp up to full speed for any reason (I.e. maybe the main motor quit etc..)?
I may just do what others her have suggested, install a mini-jack plate. BUT..I know jack plates are good to use on a long shaft motor for a short transom boat but what about the other way around? :-k
 
BloodStone said:
Yes, just like that (2nd one to the right at the top). Did you ever have to open the 15hp up to full speed for any reason (I.e. maybe the main motor quit etc..)?
Click to expand...

Thrust isn't the issue. It is a steady force. The problem is at planing speeds, where the boat is bouncing around a bit. The boat bouncing causes much more stress, impact force nonetheless, than WOT on a larger boat, where you are trolling at 3 or 4 mph with it, and the boat is more "rolling" than bouncing in the waves. Same for trailering. The impact forces are the ones that cause damage, not the steady force of outboard thrust.
 
Thrust isn't the issue. It is a steady force. The problem is at planing speeds, where the boat is bouncing around a bit. The boat bouncing causes much more stress, impact force nonetheless, than WOT on a larger boat, where you are trolling at 3 or 4 mph with it, and the boat is more "rolling" than bouncing in the waves. Same for trailering. The impact forces are the ones that cause damage, not the steady force of outboard thrust.
Click to expand...

As usual, solid sound advise from BB. Thanks! I am instead going to make a fixed solid bracket out of angle iron, 1/8" plate steel & 1.5" oak/plywood combo (I don't own or have access to an aluminum welder-so I'm using what is available to me). The fixed bracket is going to be 11" wide 12" long & 6" deep (I.e it'll sit six inches away from the transom). I'll mount it 3 inches below the top of the original transom & use the existing holes that are currently holding that adjustable trolling motor mount bracket in place.
Think it'll work...?
 
I second the general consensus. I have a little 7.5hp short shaft that I wanted to use on my boat which has a 22" transom on under 10hp limited lakes, a guy who sounded like he knew what he was talking about told me I should get one of those brackets, so I bought one, when I did the item description of course said nothing about it, but in the instructions it said a few things. First off it said not to be used at WOT. Second it said take the motor off when trailering. Lastly it said always have a safety chain when operating motor with bracket. It was described as an "outboard motor bracket" but they really should have called it an "outboard trolling motor bracket."
 

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