Self reversing Loco

LGB-Sid

LGB-Sid

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I have converted a 3 pin Gearbox to 4 pin so I can add a chip to it, The motor is 100% independent from track power, and each pickup set is 100% independent side to side all tested with a meter and power applied as well.
So I added a emotion L to it and the only things connected to the decoder at the moment in the gearbox,. Tested out on main track seems to run OK but has the odd habit of self reversing it's direction of travel ?? any ideas what can cause that ?

Decoder is good as it was tested in a Stainz and behaves 100% no self reversing.
Main track / handset tested with different Loco and no self reversing happened.


4 pin top.jpg
 
Is there a power buffer in this loco? - If so, turn OFF analogue support with CV 29.
 
No power buffer just the motor block and decoder all original electrics not connected and will probably be removed, the wheels did get aligned since the pic as when fitting the tie rod across all three it was a bit tight, not tried on analog , would need to set up a circle of track and work out how to wire the motor block pins together so it would run with out a decoder ?
 
Fro an analogue test.. Just loop each pair of pins (left pair together, right pair together) for the duration of the test.. Though with 'nothing' electronic in the 'block, I am unable to see there being a problem with the block or motor??

The fault does seem a little peculiar..
 
That sounds a REALLY odd problem.... Have you tried testing the decoder again, by putting it back into the Stainz? Just wondering if somehow it could have become damaged or corrupted when being wired up to the new chassis....?
A long shot, admittedly, but can't see any other explanation!

Jon.
 
Very odd. It does sound like the issue is at the decoder end. Perhaps a spike or break in the current is making it do odd things. Sounds bazaar but adding a little weight night just be a good idea.
 
Sounds like the decoder thinks it's getting a shuttle command somehow which is probably due to poor contact. Cv58 controls the pause time, if you put say 5 into that and find it stops for a few secs then reverses that will confirm it.
If it does then I'd suspect adding weight might help as the skates might be helping it bounce and create a serial style shuttle command?
 
Played a bit more while testing the chassis does have all its weights on so weights 2 kgs, Tried decoder in the stainz again before I put that one back together and it worked as it should do. The block I am having problems with also has an erratic speed at times beginning to think it might be worth pulling the motor out of the gearbox and checking the brushes and giving it a clean, I don't have a spare of that size so can't try a different motor in the box.

When I said I need to sort out how to wire up for analog mode I should have said I will need to make up some wires with plugs that fit on the pins as I don't have any :)
 
I setup a circle and connected a starter set analog controller to it, Loco runs erratic really on it in analog mode, so I removed the temp wires and connected a digital meter to the track pickup pins, for a block with 6 wheels and two skates for power pickup the readings fluctuate a lot as you move the block forward by hand to turn the wheels, looks like I need to take the gearbox apart again and clean all the bits that make up the electrical circuit on both sides, it's a bit crude looking to me but I assume all the gearboxes use a similar setup with a single brass strip each side trying to touch the outer casing of the brushes that touch on the back of the wheels.
 
Clean the wheel-backs, a little, where the carbon brushes contact.. Also the tyres / flanges on the wheels.. - We are talking an LGB 'block??
 
PhilP said:
Clean the wheel-backs, a little, where the carbon brushes contact.. Also the tyres / flanges on the wheels.. - We are talking an LGB 'block??
Click to expand...

Yep it's an LGB block out of an old 2074D Spreewald :) my bargain that might not turn out to be such a bargain in the end o_O
 
I'm currently (no pun intended) trying to sort out my dc wiring following a track rearrangement, I thought that was bad enough...
 
Thanks for all the reply's it's defiantly a power supply problem the voltage picked up is very hap hazard, cleaned all the wheel backs and tread area, also the inner metal power pick up strips and the carbon bush tubes it connects to , mounted the skates correctly noticed the retainers were not in correct so now the skates have the full travel they should do , I copied how they was is installed didn't realize they had been put together wrong by others.

Power pickup better but still inconsistent. will have to sit and think, I can see this is never going to be a smooth running engine at this rate.:wondering:
 
It may need running-in, but I doubt it..
There isn't a little capacitor on the motor in the block?
Tyres look a little pitted, but not enough to cause big problems??

I am thinking contaminated motor?? But not sure how that would reverse the direction??? :confused:
 
PhilP said:
It may need running-in, but I doubt it..
There isn't a little capacitor on the motor in the block?
Tyres look a little pitted, but not enough to cause big problems??

I am thinking contaminated motor?? But not sure how that would reverse the direction??? :confused:
Click to expand...

Found a thread on here on cleaning the motor so cleaned it, but it is in good condition, brushes good and in general very clean inside, and can't see a capacitor, Yep the tires are a bit worn / pitted, think I have found the problem just not sure how to fix it. The pin that feed the motor and one track pick up W/S up is causing the problem, it loses power and then gets it back and then the Loco wants / try's to reverse ?. I have made a different pin and tried it, reshaped the original pin , reshaped the strip that fits over all the pickups on that side but at times it still loses power pickup on that side of the Loco if you go too fast :mad:
 
If it is a pickup problem...
Can you solder a wire to the busbar on that side of the block? Then bring the wire out of the hole the pin would come out of??
 
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