Pontoon trailer setup

[dingbat]

I have checked the tongue weight a couple of times.

Have you weighed the rig?
You can not confirm tongue weight w/o knowing the actual weight of the rig.

It's possible the axle to coupler distance is too long for the load and the axle needs moved.

Calculating Axle Position – DIY Solutions @ Mechanical Elements

How do you know where to put the axles on a trailer? For an existing trailer, follow these instructions for calculating axle position.

mechanicalelements.com

Although, in leveling the frame of the trailer I did notice that the frame deflects a little. Maybe an inch plus over the 30’. Is this normal, I would think so.

Yes, my old trailer deflects quite a bit more with a #5,200 boat sitting on it

But as a result I did re-check the level with a tape measure a foot in front and behind the axles to make sure they were level.

Don't get hung up with the trailer being level, as in "level in hand".
Have yet to see a boat hooked to a tow vehicle perfectly level. Even my torsion trailers have a bit of a camber to them when hooked you

That did seem to make the tire sidewalks pooch out the same, but it made the equalizer slant worse.
I also did an experiment, I jacked up the rear axle on one side and noticed that because of the angle of the spring, when compressed it binds against the frame and the bushing preventing it from sliding backwards. Although the the springs /equalizer sit straight without a load, when a load is applied, not enough load to cause the bind but just a bit less, the system goes wonky.
I think this validates what I think you are suggesting dingbat, that my front springs are weak. They are probably weak because, when a bump is hit going down the road, that rear hanger binds it makes the front axle take the brunt of the force and has made it age prematurely and independent of the rear axle by pushing the shorter leafs of the springs up to/ past their yield point more often…..if I’m right, this makes me wonder why this is occurring. Are the springs the correct springs? A flaw in the design?

Nothing wrong with the design per say. I put 20 years and 100,000+ miles on the trailer I retired this Spring.

Thoughts?

Bear in mind that the trailer wasn't designed for your boat. You have to adjust the trailer to accommodate the boat.

Everything is a guess until you weigh the rig and do the math to confirm compliance. Once that is done the problem should be obvious, if one exists at all

Load rating of trailer?
Estimated weight of boat?
Actual weight of combo?
Recommended tongue weight?
Actual tongue weight?
Mfg. recommended hitch height?
Axles in the proper location?

 

[3ric]

Have you weighed the rig?
You can not confirm tongue weight w/o knowing the actual weight of the rig.

It's possible the axle to coupler distance is too long for the load and the axle needs moved.

Calculating Axle Position – DIY Solutions @ Mechanical Elements

How do you know where to put the axles on a trailer? For an existing trailer, follow these instructions for calculating axle position.

mechanicalelements.com

Yes, my old trailer deflects quite a bit more with a #5,200 boat sitting on it

Don't get hung up with the trailer being level, as in "level in hand".
Have yet to see a boat hooked to a tow vehicle perfectly level. Even my torsion trailers have a bit of a camber to them when hooked you

Nothing wrong with the design per say. I put 20 years and 100,000+ miles on the trailer I retired this Spring.

Bear in mind that the trailer wasn't designed for your boat. You have to adjust the trailer to accommodate the boat.

Everything is a guess until you weigh the rig and do the math to confirm compliance. Once that is done the problem should be obvious, if one exists at all

Load rating of trailer?
Estimated weight of boat?
Actual weight of combo?
Recommended tongue weight?
Actual tongue weight?
Mfg. recommended hitch height?
Axles in the proper location?

The trailer is rated for a 3500# load according to Karavan. The estimated weight of the boat is; 1805, fuel 200, motor 400/total2405 lbs. I need to find a local scale to get actual weight. And I can call Karavan back to find out recommended tongue weight. The recommended hitch height is 21 1/2 (which seems crazy high if you ask me).

Using the equation from the link you provided and just estimated weights, the axles are about 1.75” too far back. But I will try and find a local scale that I can use to get some real measurements. Is 1.75” significant when it comes to axle placement?

 

[3ric]

The trailer is rated for a 3500# load according to Karavan. The estimated weight of the boat is; 1805, fuel 200, motor 400/total2405 lbs. I need to find a local scale to get actual weight. And I can call Karavan back to find out recommended tongue weight. The recommended hitch height is 21 1/2 (which seems crazy high if you ask me).

Using the equation from the link you provided and just estimated weights, the axles are about 1.75” too far back. But I will try and find a local scale that I can use to get some real measurements. Is 1.75” significant when it comes to axle placement?

Thank you everyone for their insights and help. A little follow up… I took the boat and trailer to a respected trailer place. He said he took it in his shop and lifted it etc. The owner said, “the equalizers are equalizing. But it’s just a poor design. If it were mine, I’d drive it as is.” I think his reference to poor design has to do with the hooks on the rear springs binding on the bushings because the hanger appears to be a touch too short or something, preventing the spring from sliding backwards as far as it probably needs to. Thanks again everyone