the jockey wheel has to be able to spin and turn freely but the longer the leg the more it will bend.. wind it down (lower the front of the van) as much as you can..
wind it back up when near the tow ball..
the larger blow up wheels pose less rolling resistance (on soft ground)than small solid ones..
when using the mover stand near the jockey wheel and observe whats happening.. a mover can bend a jockey wheel easily if for some reason its not rolling..
Never had an issue with my smaller solid wheel. I lower the whole thing as much as i need and only wind out a couple of inches to allow the wheel to turn. There are notches in mine to stop it spinning when wound fully in.
How heavy is the front of the van? How much can you lift? If you can lift 75kg+ then the vans way too heavy unless you have a RangeRover or Doscovery etc that can take 150kg. But i think the ALKO hitch its limited to 100kg?
There are some rubbish pneumatic jockey wheels on the market - especially on ebay. My van weighs nothing, but i wrecked two wheels within 10 feet of moving the van. The centres just rip out of them. It may not be weight problem at all here.
there are some rubbish jockey wheel assemblies in their entirety.. mine has a blow up split steel rim wheel and to be honest its the strongest part of the entire assembly.. :)
when starting off they need watching to make sure the leg isnt too long and the wheel isnt back to front or sideways on.. a mover has the power to bend the average jockey wheel assembly quite easily..
i have come close to wrecking mine several times until i learned to keep a careful eye on it and make sure the leg is as short as it can be..
crappy (cheap) jockey wheel assemblies and user error.. the things are are not entirely idiot proof.. he he
i have about 100 kg maybe a tad less on mine.. it stands the weight okay.. its the initial bending loads caused by the mover that can easily wreck them..
I've had similar issues with mine. A previous owner must have towed it without securing the jockey wheel correctly and now the clamp doesn't clamp it up squarely. The result being a jockey wheel at an angle.
In the end I had a bracket made up that bolts to the a frame with a side mounted jockey wheel. It's still not perfect but it's a sight better than it was.
they are much weaker when bent back at an angle.. which is what happens to a lot of them.. a better (stronger) design would have the leg angled slightly forward.. the bracket often isnt strong enough and it lets the leg bend at a permanent backwards angle..
trog
ps.. a tip to avoid breaking them.. have a small length of 2 x 4 timber cut to the correct lengh.. put it under the hitch and lower the jockey wheel on to it. take the weight off the jockey wheel with the timber.. the wheel can be turned around to face the right way relative to the direction the van is going to move.. the destructive forces happen when the wheel is trying to castor around from facing in the wrong direction..
The jockey wheel must be wound down sufficiently to clear the (usual) inverted U shape in the JW tube which is there to stop the JW unwinding itself when on the move. If the yoke to the JW is not clear, the JW cannot castor properly so will be fixed in one direction.
As mentioned the handbrake must be off and the brakes not seized on. Even if they are stuck on,pulling the van forward should cause them to release.
Separately, JWs are rated for the load they can carry, so choose a wheel that can accept whatever the hitch is rated for - most ALKOs are rated at 100Kg - plus a good margin to allow for kerbs and the like.
Some older vans (not sure about the more modern ones!) have a little switch or lever which disengages the brakes, which will lock on when the van is going backwards. I have a lever on mine. Have a look to see if you have one of these, as it might make all the difference.
Anther thing I thought of is that the motor mover doesn't go very fast for obvious reasons. Mine goes at less than walking pace. Are you expecting the mover to go faster than it is capable of? ~This might be the case and there is nothing wrong here at all.
I have a wider and solid jockey wheel on my caravan. The thin ones didn't work with the loose shale drive surface at all, the blow up ones always needed blowing up. No probs at all since I got a wide and solid one.
Picking up a caravan by the jockey wheel is all relative. I can't pick mine up at around 50k, my son can literally move it around the drive with one hand!