Heljan class 33 running in one direction only

[Kris]

I have a Heljan class 33 that has a fault that has appeared today. 

 

After a short period of running this morning it refuses to run in one direction. In the other direction it runs without any problems. On attempting to run in the affected direction, it starts to move briefly then stops with the controller indicating that it is drawing more current than can be supplied. 

Before the fault occurred it was running with no problems at all. 

 

I have no idea how old the model is as I bought it second hand so warranty repairs are out of the question.  

 

Any suggestions?

[Geep7]

1 hour ago, Kris said:

I have a Heljan class 33 that has a fault that has appeared today. 

 

After a short period of running this morning it refuses to run in one direction. In the other direction it runs without any problems. On attempting to run in the affected direction, it starts to move briefly then stops with the controller indicating that it is drawing more current than can be supplied. 

Before the fault occurred it was running with no problems at all. 

 

I have no idea how old the model is as I bought it second hand so warranty repairs are out of the question.  

 

Any suggestions?

 

In the direction it does run, do you get a clicking sound as it runs? If it does, it's most likely a cracked gear that's only catching in one direction. Would require a strip down to find out which one however.

[Kris]

I shall have to try and see, 

[Kris]

Just tried. There is no clicking noise. I suspect it's some form of electrical issue as it runs very slowly for about 30cm before stopping. 

[johnb]

I'd suspect an issue with the gearing, maybe caused by wear if something is free in one direction but shifts and binds in the other when run the opposite way, maybe a bearing or the worm gear shifts just enough to catch on something.

Edited October 29, 2020 by johnb
Typo, shifts was misspelt!!!!!

[08221]

Is it DCC (fitted with a chip) or DC?

[Kris]

5 minutes ago, 08221 said:

Is it DCC (fitted with a chip) or DC?

It's a DC model. 

 

[Kris]

58 minutes ago, johnb said:

I'd suspect an issue with the gearing, maybe caused by wear if something is free in one direction but shifts and binds in the other when run the opposite way, maybe a bearing or the worm gear shits just enough to catch on something.

I will have to get the body off to have a look and see. Can't do this until tomorrow now however. 

[Kris]

Having checked this morning I can't see wear on the gears. 

[kevinlms]

Try taking a 12v power supply direct to the motor and see if it works both polarities. 

[John Tomlinson]

32 minutes ago, kevinlms said:

Try taking a 12v power supply direct to the motor and see if it works both polarities. 

That sounds a good start.

 

Even on DC presumably the loco is DCC ready and has a blanking plug. Is it possible this is defective? If it was bought second hand it's also possible it is chipped but DC enabled, and there's a problem with the chip, in which case if it runs fine both ways with a blanking plug that would be the answer. I've found with second hand stuff that the vendor may not know if there's a chip or not, only when you open it up do you find out.

 

John.

[Kris]

19 minutes ago, John Tomlinson said:

That sounds a good start.

 

Even on DC presumably the loco is DCC ready and has a blanking plug. Is it possible this is defective? If it was bought second hand it's also possible it is chipped but DC enabled, and there's a problem with the chip, in which case if it runs fine both ways with a blanking plug that would be the answer. I've found with second hand stuff that the vendor may not know if there's a chip or not, only when you open it up do you find out.

 

John.

It's not got a chip in it, I have had other locos turn up chipped unexpectedly but not this one. I've had it for a while and it was running fine until yesterday after about 15 minutes of running. I do wonder if it is the motor. I shall have to see about gutting the loco after lunch and testing it. 

[Kris]

22 hours ago, kevinlms said:

Try taking a 12v power supply direct to the motor and see if it works both polarities. 

Motor has now been checked, it is fine on its own under 12v. I have also checked it without the circuit board but attached to the wheels and gears, again fine. I suspect that the circuit board or a component on it has developed a fault.