problem with my 455 postwar derrick

[msacco]

Well, I picked this up last April at York but Have been running it on the layout for a year now. I've gradually seen the force of the pumper controlled by the solenoid coil lessen. Lately it can barely pull the pump lever down after only a few minutes. I tried the adustment screw a lot thinking it was the thermastat and recently installed a new old stock one from Hollash trains (the only place i've ever seen the t-stats listed too).

    doesn't seem to be the t-stat and I'm thinking it must be the coil. Do these go bad or just get tired from years of work. I've cleaned it out with contact cleaner and even hit a bit with a hammer just in case it was magnetized, but still very weak pumping action.

  Anyone have any ideas. I've found the coil from a parts dealer so I might try that but....

 Mike S.

[Anonymous]

Mike,

         Have you taken the plunger out and cleaning it and the tube inside the coil thoroughtly?  That is the only thing I can think of.

[msacco]

Yep, Jim I did. Got a qtip in there with crc contact cleaner and then did the same to the plunger. This one has really got me stumped.

   I raised the voltage to 17 volts and it's a little stronger but nowhere performing like it did when i first installed it. Use to pump strongly at 14 volts or so.

 

Mike S.

[Anonymous]

Mike,

        This certainly is a strange problem.  Have you tried connecting the 455 to its own transformer?  If there is anything else on the circuit with the 455, it might not be able to draw the amount of current that it needs.

[msacco]

Okay, I finally figured this one out. And it was a duh! I guess I just missed it.
The solenioid coil has a bracket that is twist tightened at the base of the derrick. Apparently the coil was not seated perpedicular or lined up with the coil plunger properly. This was causing it to be weakly drawn into the coil's tube.

    A little tinkering with the coil and bracket and a spot of CA in strategic places has made it run like new again.

  Thanks for jumping in and offering to help on this Jim.

 

Mike S.

[Anonymous]

Anytime, Mike.  It always seems to be that the solutions to our problems are simple, and we overlook them.  I had an equally frustrating problem when I decided to change the distributor on my car.  After installing the new one, the ignition timing wouldn't advance like it should.  After two months of trial and error, and aggrevation, I put the original distributor back in.  Car ran great.