Moving roller position on a 1989 Shoreland'r

rolmops

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Feb 24, 2002
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I have restored a 1989 22 foot 4.3 liter Starcraft Islander sitting on a 1989 single axle Shoreland'r trailer and added 2 batteries (40 pounds each) and a Suzuki extra longshaft (125pounds) to the transom area.
In order to realign the weight distribution I pull the boat farther forward on the trailer, that has caused the rear rollers on the back to stick out behind the boat just about 2 inches which causes the rollers to hit the transducers (chirp and DX4). The roller set up is the see saw type, the pivot center of which is attached to the trailer frame with a single heavy bolt on each side. The trailer frame has three bolt holes on each side, interspaced at six inches. Right now the pivot center is in the farthest back position. I am thinking about moving the pivot center to the next position forward, thus giving me an extra six inches of space at the back. I hope that by doing this, the weight distribution will bring more weight to the tongue as well save the transducers. For weight distribution I am also thinking about moving the trailer axle a few inches farther back, thereby shifting more weight onto the tongue
But as we all know, good intentions often turn into bad results. Do my plans make sense? Are there better alternatives?
PLease give me your opinions and advice.
 

dingbat

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Joined
Nov 20, 2001
Messages
16,066
I have restored a 1989 22 foot 4.3 liter Starcraft Islander sitting on a 1989 single axle Shoreland'r trailer and added 2 batteries (40 pounds each) and a Suzuki extra longshaft (125pounds) to the transom area.
In order to realign the weight distribution I pull the boat farther forward on the trailer, that has caused the rear rollers on the back to stick out behind the boat just about 2 inches which causes the rollers to hit the transducers (chirp and DX4). The roller set up is the see saw type, the pivot center of which is attached to the trailer frame with a single heavy bolt on each side. The trailer frame has three bolt holes on each side, interspaced at six inches. Right now the pivot center is in the farthest back position. I am thinking about moving the pivot center to the next position forward, thus giving me an extra six inches of space at the back. I hope that by doing this, the weight distribution will bring more weight to the tongue as well save the transducers. For weight distribution I am also thinking about moving the trailer axle a few inches farther back, thereby shifting more weight onto the tongue
But as we all know, good intentions often turn into bad results. Do my plans make sense? Are there better alternatives?
PLease give me your opinions and advice.
Moving rollers bunks and axles sounds pretty drastic for only adding #200 to the transom.

Normally, you position the boat on the trailer to get the proper tongue weight, the rest pretty much falls in place.

Is the trailer designed to handle a 22’ boat?
What is the calculated weight of your boat/trailer combo?

If you still can’t get tongue with then you move the axle, although my trailer came with a warning not move the axle more than X from factory placement
 

cyclops222

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Mar 21, 2024
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Is the trailer correct for the boat type ? Problems come up when a ...INBOARD BOAT trailer is used under a OUTBOARD boat. Have seen new boats with the wrong type of boat & trailer together.
 

rolmops

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I will go to a weight station and weigh the car + trailer and then the car with the trailer attached but not on the scale and last, the car only. That should give me the basic information that I need. I did move the axle about 3 inches farther backward. Maybe that will make the difference.
I'll be back with those numbers.
The trailer is the original one that came with the boat. I did lengthen the tongue bar by a little over a foot because moving the boat forward forced me to move the winch stand forward as well and it came closer to the back of my car than I liked.
 

dingbat

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Nov 20, 2001
Messages
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I did move the axle about 3 inches farther backward. Maybe that will make the difference.
I'll be back with those numbers.
The trailer is the original one that came with the boat. I did lengthen the tongue bar by a little over a foot because moving the boat forward forced me to move the winch stand forward as well and it came closer to the back of my car than I liked.
Something to think about…extending the distance between supports (axle and hitch) can get you in trouble unless the trailer was designed for such a span.

Will not get into the math, but increasing the distance from axle to hitch by 24” increases the deflection of the trailer’s support structure by almost 25%. If you add in the additional #200 of weight, you’ve increased the deflection by almost 33%.

This may or may not be a problem depending on the original design capabilities of the trailer and exact location of the center of gravity of the boat.
 

rolmops

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Feb 24, 2002
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The weather is not really on my side so I have not been out to work on the trailer, but when I looked at the trailer roller setup I realized that the seesaw setup of the trailer on the rear end is a set of four with the center where the seesaw center connects to the trailer is very close to the axle. That means that the weight of the rear seesaw is sitting very close to the axle and no matter how much extra weight there is on the back of the boat the overall balance is much less changed than I originally thought. I bought a scale to see exactly how much weight there is on the hitch.
I think that it is at least a few hundred pounds because I cannot lift it to save my life.
 

rolmops

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Feb 24, 2002
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I moved the rear roller set six inches forward. It was actually very easy to do with a few jack stands and two jacks. Shorelander has all these predrilled holes. I could do this with the boat on the trailer by jacking it up at the transom just enough to make the roller frame move forward with the loving strokes of a 10 pound sledge hammer.
What did amaze me is that the tongue weight barely changed. On the other hand though, I can now move the winch stand forward and pull the boat farther forward without the rear rollers sticking out behind the transom and no longer endangering the transducers. So I will position a keel roller as a bumper near the place where the front end of the keel would otherwise start hitting the trailer frame. Pulling the boat farther forward on the trailer will increase the tongue weight.
 
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