Pontoon trailer setup

3ric

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My new to me pontoon trailer seems to not be set up right. I need some help figuring out what is off. With the trailer level, the equalizer is slanted forward about 15-25 degrees and the front axle tires appear to be bearing more weight than the rears based on the visual that the tires with the same psi are pooched out more than the rears.

Some notable points….has c hook slipper springs. even though the front tires are pooched out more, the rear part of the c hook on that axle does not seem to be bearing weight at the equalizer. i checked the weight distribution (with a bathroom scale so give it take) is about 7% at the tongue. The rear axle has been replaced. It is not exactly the same axle, same 2” tube, but the bearings smaller at least when looking at the hub. The hanger spacing is fixed on a single bracket so the pivot points are not adjustable. The rear axle appears to be canted a few degrees. Any ideas?
 

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dingbat

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My new to me pontoon trailer seems to not be set up right. I need some help figuring out what is off. With the trailer level, the equalizer is slanted forward about 15-25 degrees and the front axle tires appear to be bearing more weight than the rears based on the visual that the tires with the same psi are pooched out more than the rears.

Some notable points….has c hook slipper springs. even though the front tires are pooched out more, the rear part of the c hook on that axle does not seem to be bearing weight at the equalizer. i checked the weight distribution (with a bathroom scale so give it take) is about 7% at the tongue. The rear axle has been replaced. It is not exactly the same axle, same 2” tube, but the bearings smaller at least when looking at the hub. The hanger spacing is fixed on a single bracket so the pivot points are not adjustable. The rear axle appears to be canted a few degrees. Any ideas?
Had the same situation.
Called my trailer manufacturer to see what was going on.
Was told to confirm hitch height was within the specified height range (18” to 21” from ground level to ball centerline) and the tongue weight was within specification.

In the end, my ball height was low and the tongue weight was over the mfg. recommenced 7% for my trailer. Raising the hitch up (shorter receiver drop) to specification did the trick.
 
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3ric

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Had the same situation.
Called my trailer manufacturer to see what was going on.
Was told to confirm hitch height was within the specified height range (18” to 21” from ground level to ball centerline) and the tongue weight was within specification.

In the end, my ball height was low and the tongue weight was over the mfg. recommenced 7% for my trailer. Raising the hitch up (shorter receiver drop) to specification did the trick.
I used the trailer jack today and raised it all the way up and then lowered it all the way to see if it had any affect on the equalizer position. If I lowered it all the way down it definitely became worse and raising it all the way up improved it, but still never reached level. I also just to experiment, put a floor jack under the back then the front axle. When I tried to lift the rear axle more, the jack lifted it easily, it just augmented the problem. When I lifted the front it strained the jack much more and did not move the whole thing that much.

What is strange to my little mind is that it seems that the front axle is bearing most of the weight, but the c hook/slipper end of the front axle spring does not seem to be doing anything. I can move the bolt a tiny bit, but very easy. Almost no resistance.
 

dingbat

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I used the trailer jack today and raised it all the way up and then lowered it all the way to see if it had any affect on the equalizer position. If I lowered it all the way down it definitely became worse and raising it all the way up improved it, but still never reached level.
What is this relative to the specified 18-21" center of ball dimension?
What is strange to my little mind is that it seems that the front axle is bearing most of the weight, but the c hook/slipper end of the front axle spring does not seem to be doing anything. I can move the bolt a tiny bit, but very easy. Almost no resistance.
Should not be carrying much of a load. In theory, total load/4.

The bushing/roller, as well as the eye connections should be able to move freely. Make sure the rear eye connection isn't too tight or seized.

Have you weighed the rig to confirm the weight?

Boats/trailer combos are notorious for being much heavier than thought
 

3ric

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What is this relative to the specified 18-21" center of ball dimension?

Should not be carrying much of a load. In theory, total load/4.

The bushing/roller, as well as the eye connections should be able to move freely. Make sure the rear eye connection isn't too tight or seized.

Have you weighed the rig to confirm the weight?

Boats/trailer combos are notorious for being much heavier than thought
 

3ric

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I am not sure what you mean by the 18-21” under ball hitch. The trailer is level at 15.5-16”. I double checked the weight with my bathroom scale at the ball socket and it’s 230 lbs which is right at about 7%. But, no I haven’t actually weighed it. I probably should.

so I just went out and checked if the slipper hook was stuck. While it is not being pinched by the hanger and the bushing is moving properly, it does seem to be pushing up against the frame, as in it can’t slide any further because of its angle, it’s up against the frame. I am thinking because of its angle, it is hitting the frame which is causing the rest of the force to push up on its side of the equalizer, pushing the other side down. Which then moves the pressure to the front axle. Any idea why this would be happening? It seems like if both slipper hooks were in the equalizer it would prevent this condition. Is the spring backwards? I attached pics of the slipper hooks

I did mic the springs, both the individual leafs and stacks mic’s the same. I also measured the length best I could and they appear to be the same length
 

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dingbat

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so I just went out and checked if the slipper hook was stuck. While it is not being pinched by the hanger and the bushing is moving properly, it does seem to be pushing up against the frame, as in it can’t slide any further because of its angle, it’s up against the frame. I am thinking because of its angle, it is hitting the frame which is causing the rest of the force to push up on its side of the equalizer, pushing the other side down. Which then moves the pressure to the front axle. Any idea why this would be happening?
The Springs flatten when loaded. Given the loads involved, they would have no problem moving in and out of that hanger.
It seems like if both slipper hooks were in the equalizer it would prevent this condition. Is the spring backwards? I attached pics of the slipper hooks
Eyes face to the front of the trailer
I did mic the springs, both the individual leafs and stacks mic’s the same. I also measured the length best I could and they appear to be the same length
By chance, did the PO change the springs on the rear axle?

Ideally, you want to replace both springs on a side to keep the spring rates the same between axles. An old spring is not going to have the same spring rate as new

Checked for a broken spring pack?
The springs on my old trailer looked fine, but rusty.
Loosed the spring clamp to install a new spring.......half of the old inner leaf fell on the ground. Broke right at the location pin hole.

Since the trailer has been reworked, I'd start from square one and confirm everything.

Contact your trailer manufacturer to determine the proper ball height, regardless if the trailer sits level or not. Would also confirm the leaf spring load rating and length as FYI.

I would remove the boat to see if the equalizers level w/o the weight on it.
No = mechanical issue
Yes= weight distribution issue

Check the center of gravity relative to center line of the two axles. My boat builder was able to send me a drawing with this information.
CG should be just slightly forward of the center of the axles with tongue weight set properly.
 

3ric

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The Springs flatten when loaded. Given the loads involved, they would have no problem moving in and out of that hanger.

Eyes face to the front of the trailer

By chance, did the PO change the springs on the rear axle?

Ideally, you want to replace both springs on a side to keep the spring rates the same between axles. An old spring is not going to have the same spring rate as new

Checked for a broken spring pack?
The springs on my old trailer looked fine, but rusty.
Loosed the spring clamp to install a new spring.......half of the old inner leaf fell on the ground. Broke right at the location pin hole.

Since the trailer has been reworked, I'd start from square one and confirm everything.

Contact your trailer manufacturer to determine the proper ball height, regardless if the trailer sits level or not. Would also confirm the leaf spring load rating and length as FYI.

I would remove the boat to see if the equalizers level w/o the weight on it.
No = mechanical issue
Yes= weight distribution issue

Check the center of gravity relative to center line of the two axles. My boat builder was able to send me a drawing with this information.
CG should be just slightly forward of the center of the axles with tongue weight set properly.
I don’t think the PO replaced the springs when the axle was replaced, they all four have very similar age indicators.

I looked for a broken spring pack and didn’t see one, but I did elevate one side of the trailer and the equalizer leveled out perfectly. Is this a strong indication of poor load distribution, you say? I may need you to elaborate. Is this different than tongue weight?

I’ll try and get ahold of Karavan, they were minimally helpful last I contacted them. But maybe with a specific question they can be more helpful.

Thank you for helping me
 

3ric

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So maybe you can make sense of this …. I spoke with Karavan about the ideal ball height, they said 21 1/2”! And that is measured at the bottom of the coupler. The jack on the trailer only goes above the floor 23”, not leaving enough room for the ball to slip under.

But while I was out there, I used the jack to lower the tongue as high as it would go and that made the problem significantly worse (more slant to equalizer). And if I lowered it all the way down, it would get a bit better, but still would have some slant.
 

flashback

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Been following your thread and IMHO I think the perfection your striving for is somewhat of a lost cause. The equalizer is doing what it's meant to do..
 

bruceb58

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It will do this if there is more load on the rear axle of the traieler hence the reason its called an equilizer
Been following your thread and IMHO I think the perfection your striving for is somewhat of a lost cause. The equalizer is doing what it's meant to do..
I have been following this thread as well and I totally agree. In an ideal world where both axles have identical weight and each spring deflects equally, the equalizer will be level. Problem is, the springs likely deflect differently, which may be cause by just the stupid open hook design....the weight may even be different which causes the equilizer to tilt and doing it's intended purpose.

Would be interesting to mount a small go pro or equivalent on the traielr and watch the equalizer function as it travels down the highway...may explain a lot. I bought a cheapy $50 camera for just this purpose...to monitor suspension issues while I am driving.
 

bruceb58

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So maybe you can make sense of this …. I spoke with Karavan about the ideal ball height, they said 21 1/2”! And that is measured at the bottom of the coupler. The jack on the trailer only goes above the floor 23”, not leaving enough room for the ball to slip under.

But while I was out there, I used the jack to lower the tongue as high as it would go and that made the problem significantly worse (more slant to equalizer). And if I lowered it all the way down, it would get a bit better, but still would have some slant.
Drive your trailer to a flat parking lot. It can slope as long as the slope is the same between the front and rear of the trailer.

Get the trailer parallel to the ground by measuring at the front of the trailer and the rear and get them to be equal by raising/lowering your tongue. Then you can measure your coupler height. You can also see where your equilizer is at this point.
 

3ric

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I’d like to agree with the idea that it’s fine the way it is. But when you consider that there is 2400# sitting on a trailer designed for 3500 (that will be cruising 70 mph down the highway) on tires designed for ~1500 lbs each, although that leaves a decent margin for error if the load is evenly distributed, I question the margin if the load is not evenly distributed. And I can see that it isn’t because the front tires are squished out more than the rears.

When I look at other trailers, they don’t seem to have slanted equalizers. And I agree that the equalizer is doing its job, but I question why it is having to work so hard. Also, when I place a jack under each axle it seems evident that the front axle springs are under more stress than the rear. I would think that means the yield point for the front axle is closer than for the rear and stiffening the suspension in the front axle.

But to counter point myself. I know very little about trailers and the deeper I dig into the subject the less I feel I know. One would think they would be pretty simple devices. I very much appreciate everyone’s input.
 

3ric

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Drive your trailer to a flat parking lot. It can slope as long as the slope is the same between the front and rear of the trailer.

Get the trailer parallel to the ground by measuring at the front of the trailer and the rear and get them to be equal by raising/lowering your tongue. Then you can measure your coupler height. You can also see where your equilizer is at this point.
I did level the trailer as you described, the equalizer actually looks worse when I did that. (I had been using a level at the tongue). But I did find that the trailer is bent about an inch or so from front to back, but I figure that is just the flex of the steel. But when I made the tongue match the tail, it was even worse than before
 

bruceb58

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I did level the trailer as you described, the equalizer actually looks worse when I did that. (I had been using a level at the tongue). But I did find that the trailer is bent about an inch or so from front to back, but I figure that is just the flex of the steel. But when I made the tongue match the tail, it was even worse than before
Of course that won't work if the ground your trailer is sitting on is not level. You need to check with the trailer parallel to the ground.
 

bruceb58

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If you want to improve your suspension, ditch the springs with hooks, get springs with eyes on both ends. The one end will be with a bolt to a fixed spring mount and the other end will go to the equalizer with shackles.

This is my travel trailer in which I just replaced all 4 springs yesterday.PXL_20231027_004148449.jpg
 

3ric

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So is the consensus that there is nothing wrong with the suspension? The slanted equalizer is not indicative of something being off? And that non-slipper springs might be an alternative to the current set up? What would be some reasons not to switch to non-slipper springs?
 

dingbat

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So is the consensus that there is nothing wrong with the suspension? The slanted equalizer is not indicative of something being off? And that non-slipper springs might be an alternative to the current set up? What would be some reasons not to switch to non-slipper springs?

The need for tongue weight forces the center of gravity forward of the center line of the axles, causing an unbalanced loaded on the axles.

If the (forward) springs are not stiff enough to support the additional weight on the front axle, you're going to get more deflection on the forward spring than rear. Thus the tilted equalizer.

My problem began after putting all new #1,750 springs on a #5,300 rated trailer.
5300/4= 1325

Called Loadrite and was advised they use #2,350 springs to accommodate for the additional load related to tongue weight. Swapped out the springs, problem solved

I suspect you have the similar problem, which is why I asked if you've sure of the tongue weight. Excessive tongue weight would only exaggerate the problem.
 

3ric

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I have checked the tongue weight a couple of times. 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. 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. 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?

Thoughts?
 
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