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 For Your Trailer – 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 For Your Trailer – 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

 

[3ric]

Ok, so I just couldn’t take it, I just can’t accept that the trailer is ok with the equalizer slanted as bad as it is. So after staring at it for countless hours I came up with this hypothesis, and I’d love some critical review.

The trailer has brakes on the front axle. The brakes are the kind that use the weight of the trailer to push the brake cylinder. But you have to have it hooked up to the truck to have an electric solenoid or something bypass the cylinder to back up. Well, I noticed that the front axle sits a little back in its wheel well (see photo, but still hard to see because it’s shifted back only about 1/2”).



What are the odds that the previous owner tried to reverse the trailer without the electric release hard enough that it flexed it backwards enough to soften the springs just on the front axle. Which might account for the wheel sitting back in the well and the slanted equalizer.

I was thinking of replacing the front leaf springs. Thoughts?

 

[bruceb58]

What are the odds that the previous owner tried to reverse the trailer without the electric release hard enough that it flexed it backwards enough to soften the springs just on the front axle

Not a chance!!

 

[cyclops222]

deleted

 

[3ric]

So I called Karavan to get the specs for the springs for this trailer. They told me there has been an update to the type of springs for this trailer. So I ordered a set (all 4). What arrived in the mail were hook end 4 leaf springs. He told me the new springs were going to be 4 leaf, but did not say anything about them being hook end. The previous springs were c-hooks. However, the hook end would theoretically resolve the binding of the rear end of the original rear end c-hook.

Buuuuut, I have them all installed and it doesn’t look right. The rear axle is sitting at an angle. I have not torqued everything down, so when you look at the pics, don’t panic. I’m not ready for a test drive yet. But it appears as though the rear end of the rear spring needs a spacer or something between the top of the leaf and the frame to bring it down to the height of the equalizer. It’s like the rear hanger needs to be longer. Am I missing something?

 

[bruceb58]

Doesn't seem like your trailer is designed for hook end springs. What does Karavan say when you show them these pictures?

I may have said this before...I would get eye end springs and use shackles on the opposite ends from the equilizer. That of course assumes your hanger is in the correct place which you would have to measure and see.

I hate hook end or C hook end springs...WAY too noisy.

 

[3ric]

Doesn't seem like your trailer is designed for hook end springs. What does Karavan say when you show them these pictures?

I may have said this before...I would get eye end springs and use shackles on the opposite ends from the equilizer. That of course assumes your hanger is in the correct place which you would have to measure and see.

I hate hook end or C hook end springs...WAY too noisy.

I contacted Karavan, but they haven’t responded yet. But I am struggling to think you are wrong about just getting closed eye springs and moving on with my life.

 

[3ric]

It wasn’t easy, and very time consuming, but I finally received the correct springs from Karavan. They were pretty much the same springs as were original, but with an extra leaf. Installed them and now equalizer sits pretty darn close to level. Problem solved