Lowering the bunks . . .

tpenfield

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Since I might be taking my boat out in the next few weeks for some un-planned maintenance, I wanted to lower the bunks to make retrieval and launching a bit easier. The trailer has quite a few adjustments. . . height, spacing, etc.

The increments are 1.5" on the height, and it looks like can go as much as 3" lower, but I'm doing just 1.5" to start. The keel had about 5-6" of clearance, so it should be fine. The bow bunks may need a tweak, but I decided to see how it fits before making any adjustments. I should probably bring some tools to the ramp, just in case.

I got this trailer at the end of 2021, and I am pretty happy with it. Mostly aluminum with stainless steel hardware, so loosening the bolts was easy. It is made to handle the salt water. I did notice that all of the brake lines are flex hose and not tubular steel. Not sure if that is an issue for long lines of flex hose in terms of line pressure. :unsure:

I need to test the brakes, because in the several launches/retrievals, I am not feeling much braking. (It has disc on all 6 wheels).
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It has 15,600 lbs. gross capacity (about 14,000 lbs.net). I could have gotten the upgraded axles (6,000 lb rating each), but this seemed like enough for my boat.
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jimmbo

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Don't forget that the Winch Post will also need to be adjusted, likely forward as well as lower
 

stresspoint

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be careful with entry angle , my old jet boat had a very low bunk set up as you can with a jet drive.
problem was on some steeper beach launching the keel would hit the center roller quite hard and lift the boat a good 4 inches on some launch and retrieval.
 

04fxdwgi25

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When you say you see much braking in launch or retrieval, are you questioning brake action when backing up? Please disregard if I read that wrong.

There won't be any braking in reverse with surge brakes.

I eliminated the surge coupler and went with EoH to have braking in reverse.
 

tpenfield

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When you say you see much braking in launch or retrieval, are you questioning brake action when backing up? Please disregard if I read that wrong.

There won't be any braking in reverse with surge brakes.

I eliminated the surge coupler and went with EoH to have braking in reverse.
Braking is when I need to stop. It seems like the surge brakes are not doing their thing and it is all up to the truck. I’ll figure it out. Usually if surge brakes are working, the trailer will stop itself.
 

Bondo

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The increments are 1.5" on the height, and it looks like can go as much as 3" lower, but I'm doing just 1.5" to start. The keel had about 5-6" of clearance, so it should be fine.

Ayuh,..... Only problem I see is the hull might drag on the axles/ cross members when launching or retrieving,.... depending on the pitch of the ramp,...
Just pad up those without it now,....
 

flashback

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I'm probably missing something but how is an inch and a half gonna help? Your ramp must be almost level..
 

tpenfield

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I'm probably missing something but how is an inch and a half gonna help? Your ramp must be almost level..
I'm actually hoping to get to 3" lower, but I want to see what 1.5" looks like on the trailer.
 

flashback

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Back in the young days I was a rigger for a sailboat distributor mostly Hunter, Catalina and J boats and we sometimes had to launch in lakes that had no deep water. We would back in as far as we could, tie a stout line to the trailer and fire up the boat and back the whole rig until the boat was free, then pull the trailer out.. it's a bit more work but my understanding is that you hopefully only do it once a year..:)
 

alldodge

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If lowering doesn't get you where you want, could change to low profile LT tires. something like 205 or 195 10 ply
 

04fxdwgi25

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Braking is when I need to stop. It seems like the surge brakes are not doing their thing and it is all up to the truck. I’ll figure it out. Usually if surge brakes are working, the trailer will stop itself.
OK, I see what you were saying. When you mentioned launching and retreiving, sounded like when backing down the ramp.

If you have discs, the bleed off / block valve (connected to the back up lights) may be malfunctioning, preventing the surge coupler from applying the brakes is where I would look 1st. Then the MC. Basically only things in circuit, other than the lines and calipers and w/ 6 calipers, can't see all 6 going crazy at once..
 

04fxdwgi25

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I'm actually hoping to get to 3" lower, but I want to see what 1.5" looks like on the trailer.
Does your trailer have target bunks for the front part of the keel on the front?

Could you possibly use a loner trailer tongue? I have seen tongue extensions that are used for shallow launch ramps to get trailer out deeper.
 
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tpenfield

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Does your trailer have target bunks for the front part of the keel on the front?

Could you possibly use a longer trailer tongue? I have seen tongue extensions that are used for shallow launch ramps to get trailer out deeper.
Yes, on the target (bow) bunks.

As for a longer trailer, it is already 37 feet long, so I'm not wanting to make it any longer. With the truck, I'm at about 56' long.
 

Scott06

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Braking is when I need to stop. It seems like the surge brakes are not doing their thing and it is all up to the truck. I’ll figure it out. Usually if surge brakes are working, the trailer will stop itself.
You can tell very easily if they are working by looking at the rotors. They will have a layer of corrosion. If you come back from the launch with the boat and the rotors still have corrosion they are not working.

I have had the rubber hoses on my 2004 trailer that I put all new surge brakes on in 2016 with no issues. I think similar use to yours in terms of a couple of trips to the boat launch a year vs a trailer boat
 

tpenfield

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Thanks for the replies. . . .

I finished lowering the bunks and did notice that the bunks have a downward slope to them as the bolt holes have been drilled at the factory.

11.5' long and 13" above the bottom of the I-beam in the front and 11" above the bottom in the back. So, a 2" slope towards the rear.

I checked a couple of the wheels and the rotors seem to be 'stuck' (surface rust) to the disc pads. I will probably have to pull the trailer forward to get them to free-up. Then I can test the brakes.
 
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Scott06

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I checked a couple of the wheels and and the rotors seem to be 'suck' (surface rust) to the disc pads. I will probably have to pull the trailer forward to get them to free-up. Then I can test the brakes.
Had the same problem last fall when I was taking my boat out pads had rusted stuck to the rotors was able to jack it up put a screwdriver in to retract the pads and then spin the wheels



Looks like the metallic in the pads rusted to rotors… sanded the rusty spot on the rotors down once the wheels were turning the remaining corrosion got ground off on the way to the ramp
 

tpenfield

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I'll probably just move the trailer forward and the weight of the trailer should get the wheels freed-up. Then I can take each wheel off, one-at-a-time, and do some preventative maintenance on the calipers (6 of them). This trailer has been in the salt 4 times. (Nov 2021, June 2022, Sep 2022, June 2023), but the brake system does not seem to be as tolerant as other trailers, I've owned. These brakes seemed to have rusted up more so than my 24 foot tandem axle trailer, which always seemed to work in the salt.
 

tpenfield

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The boat is now on the trailer and this is my first look at the result of lowering the bunks. Looks OK . . .
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I certainly would not want to go any lower as there is only a few inches of clearance from the keel to the cross-members.
 
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