Large Scale Central

Bachmann Heisler Pickup Problem

Problem Solving
#1
Hi All

Chapter two in the faulty pickup adventure (there are 4 chapters...;( )

My Bachmann Heisler, not sure how old, but had little running, had been fussy as the rear truck would stall now and then. I finally put it on the bench, and using the power supply determined that rear truck was not operating properly. The truck is suspended under the bunker with a screw into a rod, and there are 4 contacts, two for motor and two for pickups. These use copper strips on top of motor block and a system of 4 pins, two brass ones which I think are pickup power up and two gray metal ones which I think are motor power down. They contact a set of 4 thin copper strips under a plastic piece in the bunker.
This allows the truck to swivel and tip. Well, the 4 screws that hold the upper contact plate in place had unscrewed themselves (?) but somehow due to residual magnetism, were still hanging around. So I put them back, cleaned both contact surfaces and put it back hoping for a cure, but, still having a contact problem. Testing seems to indicate power from the board to the motor is present, but I am having a loss of power to the motor from where the gray pin contacts the upper copper strips. I do not see where to go from here as the upper copper strips seem intact. The gray pins do not seem to drop down and up as freely as the brass looking pins that conduct power up from the truck. I would welcome any thoughts on this issue
Thanks

Jerry
#2

Jerry, like the shay, you can take the truck off and hard wire the pick up and motor leads eliminating the contacts.

Terry

#3

Thanks Terry. Probably will come to that. Seems like only one wire, from the board to the upper copper contact, the gray pin and down to the motor is bad. Next step is take the truck apart and see if I can get wires into there to bypass the sliding contacts. And to find some of that specialized flexible wire. Not too much luck looking so far…

Jerry

#4

I bought a 2nd hand, not run shelf queen, Bachmann Heisler not so long ago. After running for a short while it started going in fits and starts. I noticed the amp meter on my Crest transformer was going in matching fits and starts. Some sort of short occurring ? Opened up the trucks and noticed a lot of the white gear lubricating grease was getting onto the small circuits boards at the bottom of the trucks (supresssors ?). So I carefully cleaned out all the excess grease and the boards. It has run perfectly fine after this attention. Possibly worth checking for this. Max.

#5

Jerry, I have never done a heisler so I can’t speak for certain. The problem seems more specific to the shays but i assume this is due to the shay being the more popular engine. I have been told though that the inner workings are generally the same.

At any rate, I don’t use special wire just regular old 20g stranded wire. I have one shay that has the soldered joints between the truck and loco the rest i ran new wire into the RC board when they were gutted for battery power. I did take a drill and open the holes a bit larger so the wires had some wiggle room.

Hope this helps.

T

#6

Max and Terry- Thanks for the suggestions. I need to open the truck up anyway and George S’s web site talks to that noise supression board causing problems for DCC installations, so I will check that out. Will let you know what happens…

Jerry

#7

It’s been years since I have seen the “noise suppression” components bother a decoder.

That’s in the same category that you need “perfectly clean” track outdoors to run DCC.

All true 10 years ago.

I’m posting because you should not open the loco for the only reason to get to the caps/inductors/etc.

Greg

#8

I rip those circuit boards fully out. They are a pain to work around, to service around, remember, one more level of Chinese Electronics.

When Bman came up with the silly six mil circuit board contact area…even one major sound supplier told me “how long do they expect THAT to last?” Well, obviously long enough to get it out of warranty.

First make sure you have right wheels on rear with continuity to right on front truck…same on left. They are hard-wired together through ANOTHER level of Chinese electronics in the tender area. I remove those, too, and probably have a dozen or more in a box.

If power routes fully, contacts are a know issue. Plunger springs can be an issue, especially if overheated even once (did I mention ANOTHER level of Chinese electronics?).

I have pickups…save them all…used to ship bags of them to Irv when he worked in Bachmann Service as they had…no…parts until the brass found out and made him stop (gee…sell more engines instead of providing parts?).

THAT was funny.

If the PC contacts are clean, spring on the plungers stiff enough…another area of concern is the retaining washer that holds the truck peg to the plate.

The washer has two ears, straight line across the hole…except the assemblers put the ears UP against the underside of the screwhead.

I always take them apart, flip the washer over, and it takes a bit of futzing around, but there are two mating slots on the truck peg…and it all fits together better when done.

Of course, these has the infamous version 2 of the questionable chuff syndrome. First being the Climax, with the contacts wired in series, so that at Warp Factor Two, just before they exploded, the rods might just stretch enough to close both at once. The Heisler is a 90 degree crank…with contacts in the top only…and it’s chuff-chuff-blank-blank-chuff-chuff-blank-blank-chuff-chuff-blank-blank-.

Due to the massive slop in the drive trains (remember “lopping”?) magnets and reed switch on a driveshaft isn’t much better. Only Bman engine I use auto chuff on.

If you need parts, other than the contact PC board, let me know, I can probably dig them up.

Oh…and did you ever notice the lack of any possibility of oiling the critical brush end bushing on the motor? And how the instruction book shows you how to do it…but you cannot?

Every. Stinking. One. that ever came through here got a full teardown and that “missing” oil port drilled in.

TOC

#9

Curmudgeon mcneely said: plungers

TOC

Toc said : plungers

#10

David Russell said:

Curmudgeon mcneely said: plungers

TOC

Toc said : plungers

Yeah. That’s what they are. Brass pins, rounded on one end, 4 per truck, flat tension springs in the very top providing downforce.

TOC

#11

This better explains it…somewhere…maybe…

https://www.youtube.com/watch?v=S_GM1UciGoQ