Trailer extension issue

[massnspace]

Issue with our new (to us, old....1990s) trailer.

Has a sliding galvanized square tube inside another larger square tube.  Slides out to extend tongue at the ramp.

We slide it out (easily), pin it, launch, leave it in the out position for the retrieval, retrieve boat, then it will NOT slide back in.  We have to find a large rock and hammer it back in, very slowly.  Takes a half hour just to get it a few feet back to the pin.  We get home, and then it slides back and forth easily. (??)

This has happened to us 3 times so far.  Every time we launch.  We now bring a sledgehammer to hit it back in.

It seems to me the inner tube is bending or twisting somehow between the launch and retrieval.  No, there is no sand or anything in it.  We have checked.

Is it possible that somehow the metal is bending or twisting when it gets hot or something?  Seems to bind up in the larger tube.

I damaged the ball hitch last time, so hitting it back in with a sledge is not a good long-term solution.

I have owned other boats with this system and never had a problem.

Ideas?

Thanks,

David
Seattle

[Dave Scobie]

So it is only after a launch/retrieve cycle it jams out?  At home it cycles freely, again, as long as the boat isn't launched/retrieved/moved with the tongue in the out position?

[massnspace]

Yes.  Only after a launch. It's almost like the salt water bends the metal, but I don't think that is possible.  At home, it slides no problem.

It seems that the inner tube is bent slightly in a convex shape.....so the weight of the boat bending it DOWN is not the issue....it seems bent UP.

We cannot figure it out.  Looking in to buying a new section of galvanized 2.5" square tube at this point.

[Wayne Howard]

Sounds like the galvanizing on the tubes has disintegrated. Do you wash the trailer tongue after launching? After retrieval? When I had my 21 footer, we pulled the extension completely out of the tongue after launching. Let it air dry. just my 0.02 worth.

[massnspace]

Galvanizing on the tubes is good.....looks near new.

Also, the tongue slides easily at home, so it is not possible for any corrosion that might cause this to go away, then reappear later.

Pretty sure the inner tube is bending or twisting

[Charles Brennan]

massnspace,  Reading your description, I was struck by one phrase:

We slide it out (easily), pin it, launch, leave it in the out position for the retrieval, retrieve boat, then it will NOT slide back in.  We have to find a large rock and hammer it back in, very slowly.  Takes a half hour just to get it a few feet back to the pin.  We get home, and then it slides back and forth easily. (??)

Is it possible that during the interval where you are out sailing, the extended tube levering against the exit aperture (the main tube housing) slowly deforms, until it has to be beaten back into place?

Have you considered immediately retracting the tube after launch, instead of leaving it in the "out position"?
One of two things would probably become apparent:
1) It continues doing the same thing it has been doing, which would tell you the failure is occurring in launch mode. For example, perhaps the angle at the ramp where your vehicle is level on the ramp, but the trailer is still coming up the ramp incline, is where it gets "bent".  I've seen tongue extension rigs where they have a small slot on the bottom of the main tube, to allow the inner tube to "jack knife" on the pivot pin to accommodate the change in ramp geometry.

2) It extends (for retrieval) and then retracts back (for road-readiness) without issue and then becomes a simple launch/retrieve process change.

Either way, it should provide some insight into your issue.

Hope this helps,
Charles Brennan

[massnspace]

Yes, we are going to try that next time.....take the extra time to push the extension back in between the launch and retrieval.  At the very least, if it is binding, we won't have to do the "hammer on it" dance.

The weird thing is that when I look closely at it (when it won't go back in), the inner tube is bent DOWN on the front and back....you would think that sitting in a lot with the weight of itself pushing downwards from gravity, that if anything it would be bent upwards on the two ends. 

Anyway, we will push it back in on our next trip and if it works, it works.  More work to extend, retract, extend and retract each trip but I guess that's the best we can do.

[Doug SC]

I haven't used a trailer extension so have a possibly dumb question. Do you unhitch the trailer to pull the extension out and in or do you use the vehicle to push it in and out? I could see how if hitched the weight on the back of the trailer might cause a bend like you describe. What are the tongue weights when extended and not extended? Something has to cause the tongue to bend. It could be weakened in the middle by repeated flexing. Another possibility might be it has a twist that causes it to bind. These are just some suggestions in case they can help and might not be relevant. I will be interested in the solution you come up with.

[massnspace]

Well we can't figure it out and will just use steeper ramps that we won't need to extend the tongue on. 

Again, the inner 2.5" tube slides perfectly when the trailer is at home, but after we launch it binds up (badly).  Our best guess is when it gets hot then cools quickly after hitting the water it somehow bends or twists....enough to cause the binding.

I had to replace the ball hitch already as I bent the other one out of shape having to sledgehammer it back in.....so now it works but we will just have to live with a "non-extendable" trailer.

Thanks to all those who tried to help...