I swapped my motor mover onto my new caravan on Saturday and whilst I was at it checked the brakes through and adjusted the shoes up on both wheels as there was a lot of travel on the hand brake. Handbrake now holds fine and is not travelling up to the stop.
When I tried the mover, I found that it is crabbing off to the left. The only possible explaination I can find is that there is more resistance on the left wheel, despite it spinning freely when jacked up. Can anyone proffer an alternative explaination; bearing in mind there were no issues with the mover on Friday when fitted to the old caravan?
Both wheels are definately being driven, but it slowly creeps left when it should be going forwards. It turns to either side correctly.
Hi had a problem with my mover last week would only drive left or right,rang manufacturer who said probably down to flat battery he was spot on, might be worth checking yours he said put battery on charge full whack for 24hrs unfortunately my battery was no good , mover is fine now with new battery
Thanks John. The battery was fully charged and both motors were running. It just wasn't going in a straight line, more of a large radius curve. Every few meters I had to stop and straighten it up. One thing that has occured to me is that the jockey wheel doesn't feel as firm as my old caravan. There is a split collar around it where it clamps up. Is this normal on the later caravans or has someone bodged the wrong jockey wheel onto it?
All i can come up with is check tyre pressures , then check the spacing from the rollers to the tyres , also check your motor connections to the slower motor .
one of the reasons is different lengths of cable leading to each motor, this causes a voltage difference which slowly crabs the van towards the motor with the longest cable run
I left the cables the original length and coiled the excess up with cable ties. But it is a good point about the resistances. I coiled wire has a higher resistance than a straight one the coil will then get warm and further increase the resistance.
The only other thing I can think of that has not already been mentioned is uneven ground. We sometimes get this a little if the ground is particularly stoney.
Could be one roller is tighter than the other as I only set it by eye. I was a bit. Concerned it could be a fault on the brakes but both wheels turn free and no sign of crabbing whilst towing.
Quote: Originally posted by LegsDownKettleOn on 16/5/2011
Could be one roller is tighter than the other as I only set it by eye. I was a bit. Concerned it could be a fault on the brakes but both wheels turn free and no sign of crabbing whilst towing.
if one is tighter than the other one could be slipping,its hard to see.just check the gap is as it should be ie.16mm..
------------- the only silly question is the one you do not ask.
Whilst all the suggestions might be the problem, my favourite and the problem I had like this was caused by alighnment.When you transfered the mover did you use the correct spacer to set each motor, and did you fit the chassi block to prevent the motors being pushed back?
Brian
------------- there are 10 types of people in this world, those who understand binary and those who don't.
I did fit the chassis block to prevent the motors being pushed back. Both motors are a little further back than they should be (20mm according to Powrtouch) at about 22mm, but both are equally spaced.
The jockey wheel is looking dubious as despite being only slightly off centre, it does not seem to be straight when clamped up due to the way it clamps up. It seems to have some kind of collar around it which doesn't appear to clamp up square.
Quote: Originally posted by LegsDownKettleOn on 16/5/2011
I left the cables the original length and coiled the excess up with cable ties. But it is a good point about the resistances. I coiled wire has a higher resistance than a straight one the coil will then get warm and further increase the resistance.
It also causes a big drop in voltage/amperage on DC circuits, far worse than AC circuits, cable can be left long but should be looped back and forth with a couple of inches between each run.
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Topic: Motor mover crabbing to the left
