Author Topic: ANOTHER valve gear issue  (Read 838 times)

0 Members and 1 Guest are viewing this topic.

ATSF_Ron

  • Crew
  • *
  • Posts: 357
  • Respect: +198
ANOTHER valve gear issue
« on: April 29, 2024, 05:29:57 PM »
0
I picked up a brand new and cheaply priced Bachmann connie, first release.  Put it on the track and thought no wonder it's a good price.  DOA.  But no.  I removed the bottom plate and gave it some oil.  Pulled to the shell to check wiring, then it ran!  Go figure.  However, it has a big of a hitch or gallop in its gait.  I believe it's the valve gear.  Unlike the Key 4-8-2s I posted about a couple months ago, everything LOOKS to be in order.  But, if viewed from above with shell off, it's apparent there's a bind in the valve gear.  It's nearly impossible to see via pic 1, but in pic 2 the tweezers point to the culprit.  The short shiny piece that connects to the black piece above it has a seemingly loose pin on which the shiny piece slides from left to right, causing a bind.  The opposite side of the loco does not do this.  Everything stays in place.  I tried gently pinching the pin with tweezers, figuring it might tighten up.  Nope.  No movement.

Steam loco tinkerers, you have any ideas?  Or should I send it back to Bachmann and let them send me a new one?

Thanks,

Ron





mmagliaro

  • Crew
  • *
  • Posts: 6368
  • Gender: Male
  • Respect: +1871
    • Maxcow Online
Re: ANOTHER valve gear issue
« Reply #1 on: April 29, 2024, 06:48:51 PM »
0
Since that little link just goes back and forth as the main crank goes around, it's highly unlikely it is causing the bind, even if it
does look loose and floppy while it's moving.  I'd start by taking out the crank screw (1, in my edit on your photo, below), if you're game.
Then hold it with tweezers and see if that little link moves back and forth without getting stuck anywhere. 

MY MISTAKE on this.  That isn't a screw at all.  It's just a cast detail on the crank. You can pry the whole crank right out with an Xacto blade, but you can't just put the screw back in and run without that rod, because there is no screw.  Regardless,
unless you can't wiggle that little rod back and forth freely with tweezers, it is highly unlikely that is your problem.

AND BE VERY CAUTIOUS ABOUT TRYING TO BEND OR SHAPE any of those metal rods, especially the short ones like this.  They are more brittle
than they look (which is a nice way of saying they are made out of something awful) and will break right off.

« Last Edit: April 30, 2024, 12:56:34 PM by mmagliaro »

craigolio1

  • Crew
  • *
  • Posts: 2458
  • Respect: +1773
Re: ANOTHER valve gear issue
« Reply #2 on: April 29, 2024, 08:06:51 PM »
+1
I have one that did the same. One set of geared wheels was turned a couple of teeth so it was out of quarter. It was an easy fix by removing the bottom plate and lifting/turning the offending driver pair one gear tooth at a time until the pump went away.

Craig.

ATSF_Ron

  • Crew
  • *
  • Posts: 357
  • Respect: +198
Re: ANOTHER valve gear issue
« Reply #3 on: April 29, 2024, 08:25:02 PM »
+1
Thanks guys. I’ll look at both options tomorrow. Been slinging dirt in the backyard today. I’m too old for that business! 🤣 Time for a cold one and some rest. Will report back tomorrow. 👍🏻

I like finding these old Connies. They are awesome runners with good detailing and pulling power. This one probably sat in a box for 20+ years. The wheels look like they’ve never been on the track.

mmagliaro

  • Crew
  • *
  • Posts: 6368
  • Gender: Male
  • Respect: +1871
    • Maxcow Online
Re: ANOTHER valve gear issue
« Reply #4 on: April 29, 2024, 11:55:12 PM »
0
Yes, once you overcome any quirks like this, they are solid runners, geared low, with a VERY good motor, and they can pull a lot of cars - 50 is not uncommon.

randgust

  • Crew
  • *
  • Posts: 2759
  • Respect: +2263
    • Randgust N Scale Kits
Re: ANOTHER valve gear issue
« Reply #5 on: April 30, 2024, 10:42:08 AM »
0
Mark (Spookshow) has a lot of comments and tips accumulated on these....

http://www.spookshow.net/loco/spec280.html


ATSF_Ron

  • Crew
  • *
  • Posts: 357
  • Respect: +198
Re: ANOTHER valve gear issue
« Reply #6 on: April 30, 2024, 11:39:18 AM »
0
Thanks Randy.  I've been to Mark's site many times.

Craig, I couldn't see any type of quartering issues on the drivers.

Max. That screw will NOT move.  I have several small screwdrivers that fit, and I can't get it to budge.  I pressed against it as hard as I dared to try and pop it loose, but didn't want to damage anything so I stopped.  Actually, after running for a bit the bind appears to be getting better.  Maybe it'll go away completely at some point.  There is still a very slight side-to-side rocking, but it's not a big deal to me.  I can live with it.  Max, if you can think of another way to pop that screw/rod assembly loose please let me know and I'll give it a try.

Thanks for all the input, guys!

mmagliaro

  • Crew
  • *
  • Posts: 6368
  • Gender: Male
  • Respect: +1871
    • Maxcow Online
Re: ANOTHER valve gear issue
« Reply #7 on: April 30, 2024, 12:54:25 PM »
0
My mistake on that crank!  It is not actually a screw on this model.  It just pries right out with a small Xacto blade.
And in fact, it isn't keyed into the hole very well, so it's not uncommon for them to come loose and just spin 'round and 'round
which can cause jamming problems.  If you do pry it out with the engine on its side (so nothing falls off the crank hole
or out of position), you CAN'T put it back in without that rod attached, unfortunately, because there is no "screw".
It is all one piece.
« Last Edit: April 30, 2024, 12:57:51 PM by mmagliaro »

ATSF_Ron

  • Crew
  • *
  • Posts: 357
  • Respect: +198
Re: ANOTHER valve gear issue
« Reply #8 on: April 30, 2024, 02:11:42 PM »
0
Max, thanks for clarifying.  And yeah, I'll be leaving that alone, LOL!

Here's an interesting thing...I put the loco shell back on and now it's dead again.  No light, nothing.  My best guess is there's a wire getting pinched or shorted inside the shell area.  In my original pic #1 there's an area right in front of the motor that could be suspect.  Also, up by the headlight is another likely spot for trouble.  With the shell off, it's fine.  No issues at all, even through curves and turnouts.  Back to poking around...

mmagliaro

  • Crew
  • *
  • Posts: 6368
  • Gender: Male
  • Respect: +1871
    • Maxcow Online
Re: ANOTHER valve gear issue
« Reply #9 on: April 30, 2024, 03:21:40 PM »
0
Max, thanks for clarifying.  And yeah, I'll be leaving that alone, LOL!

Here's an interesting thing...I put the loco shell back on and now it's dead again.  No light, nothing.  My best guess is there's a wire getting pinched or shorted inside the shell area.  In my original pic #1 there's an area right in front of the motor that could be suspect.  Also, up by the headlight is another likely spot for trouble.  With the shell off, it's fine.  No issues at all, even through curves and turnouts.  Back to poking around...

Is it an open circuit or a short circuit?   If you haven't already done so, it's time to get adept at using a multimeter.
Life diagnosing these things is so much harder without one.    To measure current, you put the meter in-line with one of the leads going to your test track.  If it pegs (or reads a "lot of current", like an amp or more in this case, where is should only be
drawing maybe 100 - 200 mA, ) you have a short.  Since the light doesn't light, and looking at those wires, that would be my guess if I had to guess.  But the meter would tell you for sure.

ATSF_Ron

  • Crew
  • *
  • Posts: 357
  • Respect: +198
Re: ANOTHER valve gear issue
« Reply #10 on: May 01, 2024, 05:48:05 PM »
0
Update. After placing another Bachman Connie on the tracks that runs just fine, this new one suddenly decided it was going to start running. I literally did nothing to it. I’m still popping that shell off again and having another look at the wiring, but for now everything seems to be fine. And it’s run a good hour on the test loop. The mystery continues. 🤷🏻🤨

thomasjmdavis

  • Crew
  • *
  • Posts: 4080
  • Respect: +1104
Re: ANOTHER valve gear issue
« Reply #11 on: May 01, 2024, 06:07:47 PM »
+1
Update. After placing another Bachman Connie on the tracks that runs just fine, this new one suddenly decided it was going to start running. I literally did nothing to it. I’m still popping that shell off again and having another look at the wiring, but for now everything seems to be fine. And it’s run a good hour on the test loop. The mystery continues. 🤷🏻🤨

It is surprising how often one can fix a broken machine by taking it apart and putting it back together.  I think sometimes, they are just looking for attention, like a 5 year old holding their breath.
Tom D.

I have a mind like a steel trap...a VERY rusty, old steel trap.

ATSF_Ron

  • Crew
  • *
  • Posts: 357
  • Respect: +198
Re: ANOTHER valve gear issue
« Reply #12 on: May 05, 2024, 08:28:49 PM »
0
Tom, no kidding! 3rd time for me. One was a DOA cheap diesel win on eBay. Opened it up, moved the motor with my finger, gave it some lube, put its shell back on and it ran. 🤷🏻