I have a Bachmann Berkshire that I applied Bull Frog to one set of the drivers several weeks ago. Last night it started making a strange ‘Ker-chunk’ sound when it went around a 24" radius curve and has a hard time getting through a number 4 turnout - I realize that is problematic anyway but it made it thorugh them before. (Yes, I am replacing all the #4’s). I assume something is binding but after an hour of looking, I can’t find anything.
Any ideas out there???
Where is the sound coming from? If inside the loco you might want to open it up to look for a cracked gear.
Do any other loco’s make the sound at the same spot?
It’s a new loco. Sounds like it is coming from the engineer side. It’s the only one that make that noise or has a problem.
The age of the loco doesn’t matter. Try running it at different speeds through the spot while watching. Another possibility is a truck might be riding up on a point or frog and dropping back down.
I did that last night. It seems like the front truck isn’t tracking correctly - but I can’t figure out the ‘ker chunk’ around curves.
Ker Clunk is a pretty good description of a cracked gear sound or broken tooth.
If it is a gear remember Bachmann has an excellent warranty. Just remember to remove the Bullfrog Snot before shipping it.
If the model allows lateral displacement of any of the drivers, you may have unintended contact in components of the rods or the valve linkage, just enough to bind and then skip with a clunk, but not enough to stop the engine. Since this happens on a curve, this is what I suspect, although these days, a split gear is almost a given, and this applies to all manufacturers. [:(]
-Crandell
I agree with suspecting a gear issue.
Thanks. Is there any way to deal with the lateral displacement because there is some movement? I will also look at the gears.
If there’s an issue there you should notice it while watching.
My BLI M1a cracked it’s tower gear shortly have I got it. It made a clicking sound all the time, not just at certain times like going around turns.
Ken
A cracked gear would seem to be the culprit. You may have inadvertently caused a weak gear to give by adding the extra grab of the Bullfrog Snot. The drivers would have slipped/ slid somewhat on the railhead on those tight turns. Selectors suggestion of a binding siderod would be the first to check though.
That will be today’s project. I actually suspect the siderod but will give it a good going over. That is, right after I re-lay a 3’ section of track that buckled with the change in temperature. Found that last night…[sigh]
Harold, the lateral motion I mentioned is purposefully engineered into the scale models so that they can negotiate the unrealistically tight curves on all our layouts. Well, unless you have radii near 100", that is.
So, there is really nothing to do about it. However, it doesn’t mean you didn’t inadvertently pinch a joint in the valve gear, or pinch a rod and now there is rubbing where there was none prior to your ‘intervention’.
I missed reading about the BFS treatment, if you did that, and it is technically possible that the extra grab brought to light a weakness in the gears.
-Crandell
If it is the lateral motion you could try a small amount of oil at each place where the parts rub. That should be done anyhow. Once again if it’s a gear simply send it back to Bachmann. About the buckling track, when you fix it make sure you leave a small gap at the rail joiners to allow for expansion.
Crandall - That is what I thought. I didn’t get to it today because we had storms and being a holiday I was busy. I will do it in the morning and if I see anything I’ll take the next step.
Thanks
Yes - I did look at that today and it’s confined to one section of flex track that was probably too tight to begin with. Add that fact to the humidity we have had and the fact that an air conditioning vent blows right on this spot and something was bound to give. I also think the benchwork in this spot needs something done to it because it’s where two pieces of plywood meet and I found they really aren’t joined properly. Fortunately it’s a place that is easily accessible so this will be an easy fix.