Mounting Bolt Compression of Transom

JacksOutrage

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Dec 31, 2023
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1998 Outrage 23 Evinrude 225

Recently acquired boat and after transporting ~300 miles noticed that one of the mounting bolts had compressed into the transom and motor has pulled away ~1/8". pics attached.

Prior to trailering, the boat had gel coat cracks, but I didn't notice any compression. The other bolt looks fine, and motor is firmly against transom.

Q1: Research says everyone goes to waterlog, but I'd like to hear thoughts on replacing washers with a transom saver (metal plate/washer) before going to worst case scenario.

Q2: I didn't use transom saver (for trailering), the original owner said that it had been trailered in the locked position several times with no issues. I should have done more research. I still need to trailer it another 400 miles to final destination but am not sure what I can/should do beyond purchasing a transom saver prior to trailering. I could tighten bolt, try to replace that washer with bigger plate (though I don't have a lift and my boat guy is in SC).

thoughts appreciated. I'm new to this forum so apologies in advance if I'm breaking any rules.
thanks, jack

IMG_7292.jpgIMG_7291.jpg
 

Scott Danforth

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start by doing a test drill into the transom.

most likely, you need to replace the transom wood.
 

flashback

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Transom saver for sure, then a substantial 2x4 block for a backing and matching bolt 1 1/2 in. Longer than original. Hopefully you finish your trip safely.
 

racerone

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A Boston Whaler ?-----Sounds like this boat needs work.----A lot of work.----Check and see if foam is waterlogged.
 

JacksOutrage

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start by doing a test drill into the transom.

most likely, you need to replace the transom wood.
Thanks for your (and others) quick response. Is it possible to measure moisture by removing the offending bolt and checking from that hole, or do I need to inspect the wood that is pulled from a drill test?

This makes my stomach hurt :(
 

racerone

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I have a 100 HP motor taken off a Boston Whaler----Boat was scrapped as it was waterlogged.----Hard to believe that these " well regarded " boats can be in really bad shape !
 

airshot

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Most rot/ damage is from the bottom up, check closest to the bottom for most accurate reading...good luck. Thst sunken bolt is not a good site !!
 

Scott Danforth

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Weigh the boat. My guess is the hull is about 400# heavy
 

dingbat

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Thanks for your (and others) quick response. Is it possible to measure moisture by removing the offending bolt and checking from that hole, or do I need to inspect the wood that is pulled from a drill test?
With no protrusions below the water line like an I/O, outboard transoms tend to rot from the top down.

A leaking transom cap is usually the culprit. The algae growing on the cap seam in your picture suggests yours is doing the same.

Pull one of the lower motor mounting bolts to see how far the rot has progressed. If you don’t find rot down below, you may be able to pull the cap, dig out the damaged wood and fill the void with Seacast or similar product
 
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stresspoint

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going against the grain here.
you may have a rotted transom but the possibility that the trailering has weakened the glass and wood is more than likely.
try bigger washers as IMO the ones there are too small , probably too thin as well.
put the new washers and test the transom by standing on the cavitation plate and bouncing , if the transom moves it will need replacing or repair .

if no movement , go enjoy your new to you boat.

OH and grab or make yourself a transom saver.
 

JimS123

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Whalers have never had any wood in the hull except for the transom.

Vintage models were cored with foam that would eventually soak up water. But, an unmolested boat should not pick up water anyway. Many failures were due to drilling holes to mount stuff, and not sealing up the fasteners properly.

That bolt did not countersink itself. Trailering an unsecured outboard is a proverbial issue.
 

JacksOutrage

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Thanks to all. I'm happy to see some less catastrophic suggestions. My immediate plan is to start by pulling the offending bolt, and then the lower to inspect. Depending on what I see (rot/not), I will test drill to confirm. My hope is that I end up adding a transom saver to the top bolts, but I realize it may be much worse.

Part of me says I should just add the transom saver and monitor the situation while I enjoy the boat.
 

dingbat

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My hope is that I end up adding a transom saver to the top bolts, but I realize it may be much worse.

Part of me says I should just add the transom saver and monitor the situation while I enjoy the boat.
Transoms savers are for designed for boats without power trim to keep the motor from flapping around while trailering.

Does absolutely nothing for the forces at work in your situation
 

tank1949

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1998 Outrage 23 Evinrude 225

Recently acquired boat and after transporting ~300 miles noticed that one of the mounting bolts had compressed into the transom and motor has pulled away ~1/8". pics attached.

Prior to trailering, the boat had gel coat cracks, but I didn't notice any compression. The other bolt looks fine, and motor is firmly against transom.

Q1: Research says everyone goes to waterlog, but I'd like to hear thoughts on replacing washers with a transom saver (metal plate/washer) before going to worst case scenario.

Q2: I didn't use transom saver (for trailering), the original owner said that it had been trailered in the locked position several times with no issues. I should have done more research. I still need to trailer it another 400 miles to final destination but am not sure what I can/should do beyond purchasing a transom saver prior to trailering. I could tighten bolt, try to replace that washer with bigger plate (though I don't have a lift and my boat guy is in SC).

thoughts appreciated. I'm new to this forum so apologies in advance if I'm breaking any rules.
thanks, jack

View attachment 393207View attachment 393208
Been there! U probably got screwed. ROT!
 

JimS123

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Transoms savers are for designed for boats without power trim to keep the motor from flapping around while trailering.

Does absolutely nothing for the forces at work in your situation
A manual tilt motor will certainly "Flop" around, i.e., experience up and down movement as the trailer bounces down the highway.

A motor secured half way up with power tilt, but cantilevered way out there will certainly add stress forces to the transom because you've changed the center of gravity.

Use one and don't need it trumps not using one and needing it.
 

dingbat

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A motor secured half way up with power tilt, but cantilevered way out there will certainly add stress forces to the transom because you've changed the center of gravity.
On my 200 HP outboard, the center of gravity in the down position is just forward of the pivot. When cantilevered up, the center of gravity actually moves onboard if only by an inch or two, which perfectly balances the motor on the center line of the transom in the "trailer up" position.
Use one and don't need it trumps not using one and needing it.
If you need to mechanically support the motor to prevent transom damage, you have no business whatsoever running the boat offshore.

In the 30+ years of boating, I've seen a number of bass boats with transom savers, but yet to see a single "coastal" boat show up at the ramp with one.

 

JimS123

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We'll just have to agree to disagree.

I've seen a complete transom fall off on the highway, taking the motor with it.

I've also read manufacturers' recommendations.

As I implied I would rather err on the side of caution. What does it cost? Pocket change. If you put it on and don't need it, what's the harm?

In any event, if your transom is rotten, maybe every little bit helps......LOL.
 

flashback

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We'll just have to agree to disagree.

I've seen a complete transom fall off on the highway, taking the motor with it.

I've also read manufacturers' recommendations.

As I implied I would rather err on the side of caution. What does it cost? Pocket change. If you put it on and don't need it, what's the harm?

In any event, if your transom is rotten, maybe every little bit helps......LOL.
Agreed, my post was just to get home and not to float it.
 

stresspoint

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there is some bad info here regarding transom saver usage.

to set the record strait i will add info that people should be aware of before using a transom saver.

a transom saver is one of the best things you can do /buy for your outboard boat """however "" there are a couple of important things to consider before thinking the transom saver is the be all and end all to transom damage.

first off when you transport an outboard boat the engine need to be set with the stop lever engaged , run the trim fully up then bring it down till it just touches the stop,
set the motor as strait as possible and lock it there , hydraulic steering will generally stay in this position cable will not.
the reason for this is so as one set of transom bolts is not taking all the loads + the motor cant flop from lock to lock randomly .
seen many people towing and the motor flopping around killing their transom when all it takes is a ratchet strap looped around the leg and locked to the trailer.

secondly , a transom saver will not save / fix / magical cure an already damaged transom, if anything it could tear bolts or worse still cause the entire transom to rip off .
reason being is the motor and trailer should not linked solidly together just set up so as the cradle sits on the leg (boat trailers by nature flex quite a bit) the sloppy or already weak transom could easily give way under rough towing conditions if the transom saver is taking all the loads.


trailering an out board boat properly from day dot using a correctly adjusted transom saver will ensure the transom will last providing rot does not take over.

always keep in mind , an out board is a very heavy apparatus hanging on 4 bolts attached to a bit of wood sandwiched between 2 very thin sheets of fiberglass and is designed to take load on water not a trailer , once its weakened that's it , there is no turning back aside from a professional replacement , not a i can fix that because i seen how to do it on a youtube botch up done by another armature that watched a youtube vid ( FWIW some of these vids make me laugh when i see the dixy cups and icy pole sticks in the background :)).

so do your best to keep that motor as stable as possible (not solid ) when towing to help minimize transom damage.
 
Last edited:

JacksOutrage

Cadet
Joined
Dec 31, 2023
Messages
7
there is some bad info here regarding transom saver usage.

to set the record strait i will add info that people should be aware of before using a transom saver.

a transom saver is one of the best things you can do /buy for your outboard boat """however "" there are a couple of important things to consider before thinking the transom saver is the be all and end all to transom damage.

first off when you transport an outboard boat the engine need to be set with the stop lever engaged , run the trim fully up then bring it down till it just touches the stop,
set the motor as strait as possible and lock it there , hydraulic steering will generally stay in this position cable will not.
the reason for this is so as one set of transom bolts is not taking all the loads + the motor cant flop from lock to lock randomly .
seen many people towing and the motor flopping around killing their transom when all it takes is a ratchet strap looped around the leg and locked to the trailer.

secondly , a transom saver will not save / fix / magical cure an already damaged transom, if anything it could tear bolts or worse still cause the entire transom to rip off .
reason being is the motor and trailer should not linked solidly together just set up so as the cradle sits on the leg (boat trailers by nature flex quite a bit) the sloppy or already weak transom could easily give way under rough towing conditions if the transom saver is taking all the loads.


trailering an out board boat properly from day dot using a correctly adjusted transom saver will ensure the transom will last providing rot does not take over.

always keep in mind , an out board is a very heavy apparatus hanging on 4 bolts attached to a bit of wood sandwiched between 2 very thin sheets of fiberglass and is designed to take load on water not a trailer , once its weakened that's it , there is no turning back aside from a professional replacement , not a i can fix that because i seen how to do it on a youtube botch up done by another armature that watched a youtube vid ( FWIW some of these vids make me laugh when i see the dixy cups and icy pole sticks in the background :)).

so do your best to keep that motor as stable as possible (not solid ) when towing to help minimize transom damage.
I appreciate all of the info on transom savers, ironically, I meant Transom Plate from my last message. Right now, I have a question before I get to trailering the boat.
Finally got time today to pull offending mounting bolt, and it's never as easy as it should be. I needed to remove a plastic bracket cover to access nut, bracket two screws, both frozen, and I sheared them both off.
So, now I'm going to be super cautious... before I start cranking on the bolt, can someone please confirm that I can remove without any additional support for the motor (i.e., 3 remaining can hold motor)? It's still in the trailering position (Evinrude has a trailering mode). Also, I have a breaker bar and 3/4" sockets but notice that they seem just slightly loose on the bolts. Is 3/4" a standard? Unfortunately, the service manual doesn't provide any documentation on mounting or bolt specs.
Thanks again!
 
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