I have not run mine yet and it will be a little while before I am able to.

Robert

Hej Caboose!

I also have some problems with my unit. There are no problems with my sound at all. But the engine starts and stops very abruptly. I have exactly the same symptoms on my 37624 F7. On the 37624 I had worse problems with very bad running and found out the magnet was not aligned properly but the problem disappeared when I changed the magnet.

But this doesn´t explain the sound problems. Watch the video I made:

My video on Youtube

Your video on #37629 looks and sounds like you've got acc & brake delay (F4) disengaged ...

@ John. The track was cleaned before this loco been tested.

@ klarinett. I have seen your video before. Interesting to hear
that you also have some problems with 37629 and 37624 before that.

I have the older 37622 with just one electric motor. This loco runs
very fine and smooth, and no problems with sound or jerking start/stop.
It seams like one motor can be a better choise than two. (My theory)

Caboose (sorry, forgot your first name and it's not in yer profile) - knowing you
for quite some time of course I had anticipated you run a clean track for testing
Mentioned it just to be on the safe side.

Funny, I too own the #37622 AT&SF F7 for many years and (let alone number of motors and
a more modern decoder generation) for me they show very similar running characteristics.
Guess our personal impressions on various models really can be a bit different, indeed ...

As a Marklin dealer, I can assure you that merely opening a locomotive to perform "routine" maintenance (cleaning, oiling, replacing brushes) will not void your warranty -- assuming you purchased this from an authorized dealer in the first place.

As for your problem with the motors not running smoothly together, I suggest that you do remove the locomotive housings and check for any pinched wires or loose solder connections. Also check to see that the decoder (21-pin) is securely affixed to the motherboard. I recently had a situation with a customer's set where the decoder was loose and pressing it on fixed the problem.

In multiple-motor setups, I've often found that uneven running can be nothing more complicated than one motor not being properly lubricated. It is a very simple matter (with these F7's) to remove the entire motor and clean out any existing lubrication. Then, re-apply lubrication and put the motors back together. The key here is to make sure you (a) use the correct amount of lubrication -- most people use way too much and (b) make sure you lubricate both motors the same.

If the problem persists, it could be a matter of the two armatures not being identical. Swapping one (or the other) with another locomotive's armature will confirm this. It's not likely that this is the problem, but if you don't want to go to the trouble and/or expense of sending this back for repair, it is certainly worth a try, and not difficult to do.

In MRR more than 90% of isues or failures are a matter of bad electrical contact...don't forget it

My 37624 runs like a dream,not a problem at all.Have you change the motor brushes?

If you have the brushes change them just to be sure there is no problem with them.I had this problem with my Rio Grande Alco,i change them very soon.The big weight of these locos maybe is responsible for this.It is your decision.

I am sorry i do not help you.I hope you find a sollution for your f7.