I just purchased a 1973 14ft aluminum boat. It's 54" wide. The trailer that it came on was in need of repair. I'm putting 8' pt pine 2x4x8 bunks on it. I have already wrapped them with bunk carpet. My question is about how far past the end of the trailer should the bunks extend? The picture is before I pulled the old mis-matched length 2x4's off and repainted and rewired the trailer. I am replacing the winch mount and adding a v-stop for the bow
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The bunks should fully support the transom. Extending them 3/4 to an inch beyond the transom is good.
There might be some bad news I’m afraid. Conventional wisdom is to avoid PT lumber because it has a corrosive reaction with aluminum. I have read in a recent thread someone saying the newer PT formulas do not have that problem. Kind of a quandary — I’m in the camp of playing it safe and using regular 2x lumber.
There might be some bad news I’m afraid. Conventional wisdom is to avoid PT lumber because it has a corrosive reaction with aluminum. I have read in a recent thread someone saying the newer PT formulas do not have that problem. Kind of a quandary — I’m in the camp of playing it safe and using regular 2x lumber.
lckstckn2smknbrls
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In your picture the bunks are hanging very far off the back of the trailer. This tells me the trailer is too short for your boat.
You probably need a longer trailer otherwise you will not be able to get the needed tongue weight to tow it safely.
And I agree don't use pressure treated wood anywhere near an aluminum boat.
You probably need a longer trailer otherwise you will not be able to get the needed tongue weight to tow it safely.
And I agree don't use pressure treated wood anywhere near an aluminum boat.
MrGiggles
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The bunks need to be an inch or so past the transom when the boat is loaded on the trailer.
In your situation it would likely be best to just start over with non treated wood, mount the bunks full length and load the boat, mark where the transom is and trim to fit. Then wrap and install them.
If the boat extends more than a few inches past that rear cross member, then the trailer is likely too short as-is. Although it may work, you will have difficulty getting the weight distribution right so it pulls decent, boats are light in the front and the trailer axle needs to be pretty far back to achieve the desired 10% tongue weight.
In your situation it would likely be best to just start over with non treated wood, mount the bunks full length and load the boat, mark where the transom is and trim to fit. Then wrap and install them.
If the boat extends more than a few inches past that rear cross member, then the trailer is likely too short as-is. Although it may work, you will have difficulty getting the weight distribution right so it pulls decent, boats are light in the front and the trailer axle needs to be pretty far back to achieve the desired 10% tongue weight.
Welcome to TinBoat's 
If you could post some pictures of the boat and some more of the trailer, we can advise of other potential issues that you may encounter.
I have seen the corrosive effects of PT on aluminum. While it can be minimized with barriers, probably not worth the risk over the cost of a couple 2x4s.
What "L" mentions, can be a very serious safety issue. You start fish-tailing at highway speeds it can go badly in a hurry. If this is a "typical" boat set-up with outboard, fuel, battery, etc then that looks to be highly likely given the picture. If this is a "light" boat, no gas motor, you can probably get enough weight on the tongue, by moving all gear and equipment to to the bow, during transport.
If you could post some pictures of the boat and some more of the trailer, we can advise of other potential issues that you may encounter.
I have seen the corrosive effects of PT on aluminum. While it can be minimized with barriers, probably not worth the risk over the cost of a couple 2x4s.
What "L" mentions, can be a very serious safety issue. You start fish-tailing at highway speeds it can go badly in a hurry. If this is a "typical" boat set-up with outboard, fuel, battery, etc then that looks to be highly likely given the picture. If this is a "light" boat, no gas motor, you can probably get enough weight on the tongue, by moving all gear and equipment to to the bow, during transport.
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The picture I posted and this one are of the boat and trailer when I first picked it up. I planned on having the bunks extend about 12-18" past the end of the trailer. I will be having a 9.9hp on the back about 75lbs. I do not plan on having the transom extend any further than the bunk boards. The way it was in the picture below, it towed properly.
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The axle is very far forward, and you will have prolems if you mount the motor to the transom during trailering. I couldn't tell if you have much room to move the winch/bow stop forward much, but you are going to want to get as much as possible. I don't think you will gain enough to transom mount and will still need gear/ballast in the bow.
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You got away with it because there was no weight in the boat !! Add a motor on the back,, fuel tank and safety gear, you will be in trouble. The good folks on here are trying to help you out with good sound , follow it, your life might depend on it!!
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If I’m looking at the 2nd pic correctly, there is way too much boat hanging back beyond the trailer’s rear cross frame (it looks to be almost half the boat). I don’t think you would be able to move the axle far enough back to get at least 10% - 15% of the total loaded boat & trailer weight on the hitch ball. I hope I’m seeing it wrong, but as others say it creates a serious issue.
PS: in my state the trlr brake lights being that far forward of the transom overhang might not be legal. Problem if you are rear ended by someone. Something you will want to check with your DMV.
PS: in my state the trlr brake lights being that far forward of the transom overhang might not be legal. Problem if you are rear ended by someone. Something you will want to check with your DMV.
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The overall trailer length is 15 1/2ft, the axel is 27" from the back of the trailer. I was going to overhang the new bunks 12-18" off the back. Giving me 1-1 1/2 ft between the coupler and the front of the boat. Will that work?
MrGiggles
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That setup will never balance right. Look at any boat trailer and the axle will be within a couple feet of the back of the boat, yours is near the middle. It almost looks like a jet ski trailer or something.
The trailer needs 3-4ft added to the tongue behind the winch post, there is no getting around it. It shouldn't cost much and it will pull like a dream, be far easier to launch, and back easier. Since it is a pretty light rig, you may be able to cut the tongue, find a piece of square tubing that fits inside or around the original tubing, and thru-bolt it together. It could also be welded if you know someone or there's a shop nearby.
I can appreciate the effort you've put in, but what you have there is a recipe for frustration and wasted time. Do it right from the start.
MrGiggles
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I'd say most trailers for that size boat are between 16 and 18 feet long. Long enough for the transom to be close to flush with the rear cross member on the trailer, with enough distance on the other end to keep the bow from hitting the tow vehicle if you go through a dip.
Looking at your photos again it almost appears as if the winch post is just too far back, many of them are bolted on and can be easily adjusted. If its welded, you may be able to cut it off and install an adjustable setup.
Generally speaking, unless you need to fit it in a garage or something, longer is better for the reasons I mentioned earlier.
Thank you
thill
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If possible, unbolt the winch post and move it as far forward as possible.
If that doesn't balance things, unbolt and move your axle back a foot or two. You should be able to do it with a 15.5' trailer.
With the boat loaded as normal, with motor, fuel and battery, you should have at least 10% of tongue weight, or about 40 lbs or so for a 400 lb rig.
If that doesn't balance things, unbolt and move your axle back a foot or two. You should be able to do it with a 15.5' trailer.
With the boat loaded as normal, with motor, fuel and battery, you should have at least 10% of tongue weight, or about 40 lbs or so for a 400 lb rig.
The pictures must be awful decieving.
I have a galvanized EZ Loader trailer ( a bolt-together from Cabella's) that I use for 14' boats. A 14' "light" boat that has had10/18hp motors on transom, and heavy w/40hp. I haven't had issues and have plenty of tongue weight. It is 16' long, coupler center to end of bunk. Axle to end of bunk is 38". Winch post to center coupler, 24" at frame level, 18" at height.
The bottomline is, you need 10% of the weight on the tongue.
I have a galvanized EZ Loader trailer ( a bolt-together from Cabella's) that I use for 14' boats. A 14' "light" boat that has had10/18hp motors on transom, and heavy w/40hp. I haven't had issues and have plenty of tongue weight. It is 16' long, coupler center to end of bunk. Axle to end of bunk is 38". Winch post to center coupler, 24" at frame level, 18" at height.
The bottomline is, you need 10% of the weight on the tongue.
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Assuming that everything else is good on the trailer you may consider taking it to a trailer shop or professional welder and ask them to extend the tongue. Or just find a trailer that fits and sell this one.
A buddy put too much weight in the back of a toy hauler camper. When the trailer went squirrelly it literally shook the camper to pieces. It was a total loss. In your case the boat would likely end up in the ditch or the front of another vehicle. The way it is set-up posses a serious safety hazard.
Thanks for the advice
Skunked again
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The above people are trying to help you. I have a 5x10 tilt utility trailer. From the factory, the axle was too far forward. It tilted like a dream, however, I couldn’t go over 53mph without it going line to line, with any weight on it. I moved the axle to the rear some, can now haul whatever I want, at any speed, with no “wagging the tail”.
Look online, plenty of info for axle placement. Rednecktrailers.com used to have an axle placement guide on their site.
For the bunks, as an alternative, remove the carpet - keep the pt wood. Put on a solid surface, of some sort, to separate the pt wood and boat bottom.
Some ideas -
- get a pvc fence post sleeve, rip it in half, secure to the bunks.
- look into commercially specific products . Such as caliber boat bunk covers, or gator back bunk covers. These are two that come to mind.
I’ve done both the pvc sleeve covers, and put gatorbacks on previous boats. Both did the intended job. As, or more importantly, removing the carpet will allow the bunks to dry in no time, thus, greatly extending the life of the bunks. Yes, you can remove the “bottom” layer of carpet, the problem is the rest of the carpet is still holding water.
A positive to the Gatorbacks (maybe others by now), if you get the clear ones, you can route a groove in the boards for led strips, put the leds on a switch, have lights to make it easier to load at night. Look up boat trailer runway lights for ideas. I did this on previous boat.
Look online, plenty of info for axle placement. Rednecktrailers.com used to have an axle placement guide on their site.
For the bunks, as an alternative, remove the carpet - keep the pt wood. Put on a solid surface, of some sort, to separate the pt wood and boat bottom.
Some ideas -
- get a pvc fence post sleeve, rip it in half, secure to the bunks.
- look into commercially specific products . Such as caliber boat bunk covers, or gator back bunk covers. These are two that come to mind.
I’ve done both the pvc sleeve covers, and put gatorbacks on previous boats. Both did the intended job. As, or more importantly, removing the carpet will allow the bunks to dry in no time, thus, greatly extending the life of the bunks. Yes, you can remove the “bottom” layer of carpet, the problem is the rest of the carpet is still holding water.
A positive to the Gatorbacks (maybe others by now), if you get the clear ones, you can route a groove in the boards for led strips, put the leds on a switch, have lights to make it easier to load at night. Look up boat trailer runway lights for ideas. I did this on previous boat.
