Bowser SD40-2

Scale:
HO Scale


This installation uses the following decoder:


This installation is for an HO-Scale Bowser SD40-2 using a TCS EU821 Diesel Decoder. This install was performed by TCS.

The Bowser SD40-2 has 7 light functions, and with its 8 lighting functions the EU821 Diesel decoder supports all of them.

Note that this is the same installation for both EU621 and EU821. The main difference between the two decoders is the EU621 is six functions and supports

Railcom. The EU821 is an eight function decoder that does not support Railcom.

HO-Scale Bowser SD40-2 prior to TCS EU821 Diesel Decoder installation. The Bowser SD40-2 has 7 light functions, and with its 8 lighting functions the EU821 Diesel decoder supports all of them.
To start off this install, we must first remove the front and rear couplers and their housings. Once that is complete, the shell will lift off of the chassis. With the shell off, we can now remove the 21-pin factory decoder from the original lighting board.
Now, simply plug in the EU821 Diesel decoder just like the original decoder. *Although, it is shown here with a speaker in place, this decoder and installation is for 8 lighting functions and is not a sound decoder. For sound, please refer to the SD40-2 WK WOW121 installation found elsewhere on this site.
Replace the shell and the couplers and your Bowser SD40-2 with the EU821 is now ready to run! Ideally we would add a Keep Alive® device to this installation, but there is physically no where to place it in this engine. Besides that disappointing element, this is one of the easiest installations out there.

Important Soldering Tip

Please do not use any flux either liquid or paste on the mother board. Over time, the acidic properties of liquid or paste flux will begin eating away at the fiberglass PCB and will damage it. Use only Rosin-core solder or no-clean flux approved for electronics use.

TCS recommends the use of Kester "44" Sn63 Pb37, .015" diameter Rosin-core solder. Kester part number 24-6337-0007.

You can order this solder from the following retailers:
Digikey - PN:KE1110-ND
Techni-Tool - PN:488SO6775

Other solder tips

When stripping wire, only strip a tiny little bit of the insulation. Strip no more than a 1/32 of an inch. When the wire gets tinned with solder, the insulation will shrink back more. Try to not expose any more wire than half the length of the solder pad at most. In no case should solder or exposed wire wire ever be outside the boundary of the the solder pad you are attaching a wire to.
Click here for important information on properly Stripping and Tinning wire