Worn out leaf spring?

Kruegs35

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Sep 13, 2015
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Recently, I just had my axle replaced because it broke. Now, when I hit a bump on the right side, the leaf spring fully extends and pops the shackle up against the trailer, so there is barely and clearance between the tire and fender. I have to jack up the trailer and ply the shackle back down. Anybody ever experience this? Is the leaf spring worn out and flexing too much, or maybe the shackle bolts should be tightened a bit?
 

G_Hipster

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Sep 24, 2016
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Over tightening the U bolts that hold the axle to the spring can cause the spring to bind and not allow it to compress properly giving it almost a preloaded state on the rebound side making it bouncy and over extending. A lot smoke the u-bolts down with an impact gun. This would be more pronounced if it was smoked down with the axle hanging and the spring extended. It's not proper and binding the spring can lead to a broken leaf within the spring pack. I don't have them handy, but there's torque value's for leaf springs and u-bolts based on the bolt size, most between 60-80 ft lbs. Nowhere near the 250 that some impacts are capable of. I would re- torque the u bolts, look at the springs carefully and make sure the shackle is not binding. With suspension, it's best to do the final torque with the weight on it at rest, run it around a little, and recheck.
 
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Idlespeedonly

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It would be great if you could post a picture so we can see what is going on.
 

Kruegs35

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Sep 13, 2015
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Axle was rusted out. Leaf springs don't look in bad condition.

I will try to post a pic soon.
 

MH Hawker

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mmm it dosnt look right by any means how is the front spring eye bushing, the spring looks like its way to long
 
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Kruegs35

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I don't know the condition of the front eye bushing. Unfortunately, I have to keep the boat at a storage facility, so I can't just go check it. I thought the same thing about the length, but I measured both sides and everything matches.

I can get a crowbar between the end of the shackle and the trailer and pop it back down, but another bump and it snaps right back up.
 

GA_Boater

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If the boat isn't stored for winter, try swapping the springs from side to side. That will tell you if the spring is causing the shackle flip.

Looking inside the wheel, is that grease or dirt? You might want to check the grease seals.
 

Kruegs35

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No, there are not shackles on both ends. GA_Boater, good idea, I will swap the springs and see what happens.
 

gm280

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To answer your first question, NO those springs are not worn out. In fact they look pretty nice. BUT, I get the feeling they are either not the original springs or the shackle mount on the trailer frame needs to be moved back. I can easily see why it is snapping into that position with the way it is mounted. I am actually surprised both sides are not doing the same if the other side is mounted the same way. The trailer shackle mounting bolt that attaches the springs should be in the very center so there is no way for it to flip forward or rearward, but still more freely. That one is obviously so far forward that the natural position is how it sits in that picture. It looks like the back shackle mount should be moved backwards the exact distance from the spring attacment bolt to the shackle mounting bolt distance. JMHO
 

G_Hipster

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I pictured the shackle flipping the other direction. Whats the shackle angle look like when it's up on the spring like it's supposed to be? The spring doesn't look to bad, but looks can be deceiving, The way the rear spring eye looks where the shackle bolt goes through looks a little suspect to me. They seldom get lubrication and can get to the point that the bolts can eat the spring eyes. I would check If you have slop on both eyes and both ends of the shackle.
 
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89retta

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I'm thinking there is a worn out bushing where the upper bolt is. Allowing it to rotate so much.
 

mla2ofus

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If the springs are the same length then I'll say someone replaced the springs with ones longer than the originals. If you just move the shackle mounts back the same distance as the spacing between the shackle bolts I think everything will be OK. Of course there is a fender bracket that will probably not allow that much so the front spring bracket may have to be moved forward also. Might be easier to just buy springs the right length.
Mike
 

Kruegs35

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Sep 13, 2015
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No, the shackle was not flipping before. I thought I had it fixed when I replaced the bolts and bushings (bolts were bent), but it popped up again a few days ago. The left spring brackets are attached to the trailer frame by welded studs, so moving them would not be easy. Also, I don't see any reason for the shop to have had to remove the springs to replace the axle.

Thought about putting a bump stop behind the shackle as a temporary solution.
 

G_Hipster

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If the problem started when the axle was changed I would go back to the axle u bolts with a torque wrench. You have to let the spring "work". Sometimes the problem is the last place that was fixed. If that doesn't help maybe it's time to look for springs
 

frantically relaxing

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Along the same theory as Hipster had, If the springs were tightened up with weight on them, they may be preloaded to the point they have nowhere to go but flat-

Try this after flipping the shackle back again...

1- loosen the U bolts
2- jack up the trailer so the wheel's off the ground a few inches
3- find a scissor jack that will fit between the axle and frame, or a large pry bar or 4x4 and strong friend--
4- with the jack or pry bar, one person push the axle down and inch or two,
5- while the other person tightens the U bolts...

This should help.

and what WILL help is a rubber snubber between the axle and frame. That should at least limit the spring's movement and prevent the shackle from flipping.
 

G_Hipster

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My thing is that if the spring plate was over tightened, the spring will be in a bind, act goofy, or break a leaf, and can/become disconnected from the trailer. I wouldn't suggest binding the spring in the other direction. Which could make it bouncy. If the springs are wore out replace the pair, a spring can look fine and still be fatigued.

Either way, it's a safety issue that needs sorted, not a band aid.
 
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