Key/Samhongsa UP 4-8-4 Question

[spookshow]

I recently acquired a 1987 (SER #53) Key/Samhongsa FEF-3. The tender pickup scheme is pretty standard Samhongsa stuff (tender wheels pick up current from one rail and transfer it to the locomotive by way of a single stiff wire on the drawbar). I've been told that the tender pickup scheme was improved on the second (2001, SER #128) production run and was wondering if anybody out there could describe to me how the revised scheme differs from the original?

Thanks!
-Mark

[superturbine]

The revised power pick up between the FEF-2,3  ser 58 and 128 were small changes that added substantially to reliability. The main changes are to the tender pilot.  A washers is added on top of the tender pilot truck to aid in power pick up and eliminates the unneeded movement of the truck.  Next the tender pilot attachment  slot is angled to allow better articulation.  Also a pin is added to the tender to keep the pilot truck from spinning around and causing a dead short. As for the centipede tendern trucks the axels are no longer press fit into the frame, now the trucks have a plate to hold them in place.  This allows the trucks to have more of a sprung effect.  ........Main point of cleaning for power pick up-  remove all tender trucks  attach  steel brush to a drimel tool and clean the brass attachment points.  Then in the same way clean the draw bar.

[spookshow]

Great info, thanks ST. Were there any changes to the drawbar, or did that remain the same between the two releases? I know that Samhongsa improved tender current conductivity in some of their later steamers by using a "U" shaped wire instead of a straight one (thus touching the tender post in two spots instead of just one).

Cheers,
-Mark

[superturbine]

The draw bar does have 2 copper wires instead of one.  Here are some pics of a #53 and #128 Tender and a series 128 engine.  The pilot of the engine is also revised, it pivots on a (centered )screw or post instead of a screw near the first driver.

[spookshow]

Thanks again, great stuff. So, how would you rate the SER 128's performance as compared to the SER 53? Out of the box, my SER 53 barely ran (what with the tender current constantly coming and going). However, performance improved significantly after cleaning up the tender trucks as you suggested. I also applied a tiny glob of solder to where the drawbar wire inserts into the drawbar (something I've often found helps out with this older style of drawbar). Stalls aren't a problem anymore, but it still runs just a bit uneven at slow speeds (and with the headlight flickering in concert with the slight up-and-down speed changes). I'd say it started out as a "D" and moved up to a "C" (almost a "B").

All of the problems with mine appear to be related to the tender pickup and how the tender current gets to the engine. So, I'm assuming that if all of these issues were addressed with that revised tender and drawbar, the SER 128's must be fine runners indeed. No?

-Mark

[superturbine]

Did you remove the pilot and complete set of tender trucks and clean the points where the screws go into the frame and the screws themselves.  Also I usually replace the pilot spring which is likely burned-up, with some fine stranded wire.... A new spring.  I would likely give the 128 B plus and  the 53 a B.  And that would be with grading the kato Kato gs4 at a A.

Btw I have dropped drivers and cleaned the boxes and frame and this also helps

[spookshow]

I unscrewed the centipede "truck" from the chassis, removed the wheelsets, stripped off all the paint and cleaned all the contact points (chassis and truck). I didn't clean the screws though, so I'll go try that.

Mine doesn't have a spring on the tender pilot truck (per se). What it has a flexible cone-shaped sort of washer-looking thing that the truck butts up against. Not sure what the deal is there, should I try adding a spring?

Thanks,
-Mark

[superturbine]

I took the stripped the insulation off of TCS decoder wire and wrapped it around the screw to act as a spring and power pick up.  Get rid of the round cone shaped washer.  Should help