Engine Surges in TMCC

How does it regulate speed...can motor flywheel with sensor? Replace any of that?

If it is Odyssey and cruise is on - the odyssey magnet could be loose.  If the magnet is loose, a drip of super glue often cures the problem.  Check this soon because when the magnet comes off all together it is usually in pieces and can take out other parts as well. 

The magnetic ring and its security was one of the first items checked. No defects found.

Thanks so much for your help and reply.

mokemike

cjack posted:

How does it regulate speed...can motor flywheel with sensor? Replace any of that?

Can motor with a sensor held on by a magnetic ring. The sensor is not loose and the can motor is secure too. Nothing replaced at that location. I know that on an MTH engine the sensor that reads a tach strip can be too far from the sensor to correctly read it. If that happens, the engine will run at the wrong speed but I've never seen a surge from an improper gap. Just wrong speed.

Thanks for your help and reply.

mokemike

I would suspect the Odyssey board. However, first double check the connections back to the driver board. 

Next look and see if you can swap the motor and reader out with another locomotive.

Can you confirm the U joint in the drive shaft is not broken or binding?

Check the gear box as well...

Does it perform the same way with TMCC and no Odyssey?

Sorry that this reply took so long but I had to wait on parts and my turn getting the tech to do repairs. Just replaced the Odyssey board under the can motor. Checked U joint and gear box although engine is new. Replacing the Odyssey board removed the surge at full speed and had a definite change at 3/4 speed. However, the surge is still present at low speeds but 70% less apparent. 

Can't find cause of low speed surges. Doesn't cause engine sound to change as surge isn't as prevalent as before. The iron ring is secure and never was loose.

low speed surge is present in TMCC and conventional operation. DCDS board was also replaced. No binding in wheels, linkage and tender wheels.

appreciate any further suggestions.

Thank you for your reply.

mokemike

I had the same problem with an Odyssey Consolidation (6-38036).  It turn out to be the DCDR motor driver board.  Lionel has them for about $110.

Danr posted:

I had the same problem with an Odyssey Consolidation (6-38036).  It turn out to be the DCDR motor driver board.  Lionel has them for about $110.

I think he has this covered.

mokemike posted:

DCDS board was also replaced.