Front truck makes thumping sound like flat wheel sound only in forward. Took truck cover off, wheel gears look good. 3 other visible gears look good. Possible hidden gear problem? Reverse no noise. I'm stumped.
Bob,
Did you try running it with the shell off to see if something became obvious?
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
NYBob,
Not wanting to sound like a smart-aleck but, what would be the result of swapping the trucks, front-to-rear, rear-to-front? Since you've done a thorough visual with no visibile cause and it only does it when the engine is goihg forward, by putting the now, front truck in the rear where it will be running in constant reverse.....? If you've taken the engine apart to check the gears, it may not be too much trouble to swap the trucks end, for end also. I don't have one of these engines so, I don't know.
t
Thank you, I didn't think of that option. It's weird because it only thumps forward under load. If I can't figure it out it may become a dummy unit. I'm sure it's over 35 years old and hard to get replacement gears.
Maybe check those gears again, real close. I had an Atlas Master serious GP38 with cracked gears.
Hold on to the wheel on one side, and try to turn the other wheel, etc., and make sure they are not cracked.
You can still get some parts on Ebay, from reputable sellers.
Mike.
My You Tube
I just ordered new gears and other parts from Atlas. Hope it fixes it.
It could be a split axle gear. If you can't see it, one way to find it would be to remove one idler gear from the truck (the one that touches the 2nd axle) and run it. If the noise doesn't go away, swap the front and rear axles and see if that changes anything. If it does, you know which gear is the problem!
I don't think the newer Atlas parts will fit the old Roco drives unless Atlas still had some Roco parts in stock. I think NWSL makes the correct gear though, and you might be able to find an original gear or wheelset on eBay or another place that has old parts.
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Correct me if I'm wrong, but wasn't Atlas Roco made in Japan, and Atlas Austria preceded that? Roco has black gears, Austria has red gears in all the Atlas engines I've ever had.
What color are the gears in the troubled loco? Dan
The gears are red. I'll check the wheel gears for splits.
The noise was a cracked gear on the wheel shaft and no replacement is available. The fix was use medium ca glue on the shaft and let it wick into the gear. When dry file off any glue on the shaft so it can rotate freel on the truck frame. So far no noise!!
Great, hopefully that fix will keep it going for a long time!
Southgate 2 Correct me if I'm wrong, but wasn't Atlas Roco made in Japan, and Atlas Austria preceded that? Roco has black gears, Austria has red gears in all the Atlas engines I've ever had. What color are the gears in the troubled loco? Dan
Roco is the Austrian manufacturer who made the red gears. Atlas did get Japanese made trains from Kato for a while before moving to another factory in China.