my ESPEE MODELERS ARCHIVE

California's Railroad to the U.S. 1861 - 1996

   Search this site or the web powered by FreeFind
 
Site search Web search
Model Train Help EBook

Fuel tank Upgrade for the Bachmann B23-7

Having got the B23-7 home and placing it on the layout, the first thing that I noticed, was the fuel tank shape. It looked horribly wrong, comparing it with an Athearn and a Rail Power chassis, it was definitely misproportioned. This can be fixed in 2 steps :

  • 1) - scratchbuilding a new plastic fuel tank and air reservoirs - easy.
  • 2) - Re-profiling the Bachmann chassis to accept the new fuel tank - not so easy.

I'll describe the hard part first, then you can decide if you wish to continue.

Bachmann, for some reason, did not make it easy to remove the motor, at least that is what I found anyway. After a lot of looking, prodding and poking, the only way I could get the motor out, was to cut the motor retaining brackets. This will require buying new brackets, Part No.6174 (don't tell me if there is an easy way, I've already ordered new brackets).

Remove the plastic fuel tank, and then the body, unsolder the 3 wires, red, black and brown. Then remove the trucks, either marking them as front and back, or noting that the brown wire is on the front truck. Remove the top motor clip, cut the motor brackets, and remove the motor.

Note: drawings are not to Scale - Please use Dimensions.

Having the chassis completely stripped down, you should see a scribed line on the side of the metal fuel tank casting. Scribe a line on the end of the casting, from this line to the existing outside bottom corner, on each end and each side. Then remove all the metal outside of this line, neatness is not a necessity, as the plastic tank will cover any mistakes. I used a cutting bit in a Dremel Moto-tool to achieve this, you can use whatever means are available to you. I wouldn't fancy doing this with the motor in place, as I don't think you could successfully stop the fine metal filings/cuttings from getting in, and ruining the motor. Re-assembly is simply the reverse of the strip down.
Image showing dimensional detail for scratchbuilt B23-7 replacement fuel tank

Having completed the hard part, the rest is relatively easy.

I used 40 thou styrene sheet exclusively for the fuel tank, 1/4 inch Evergreen tubing for the air reservoirs, and the following tools :-

  • Hobby knife,
  • small square,
  • metal rule, mill file,
  • 1/4 inch single hole punch,
  • 3/32 and 5/32 inch drill bits.
Image showing dimensional detail for scratchbuilt B23-7 replacement fuel tank

Cut 2 tank ends as per Figure 1. and clean up. Cut a tank base as per figure 2, lightly scribe a centreline, and mark the centres for the 5/32 in. holes, (these holes will clear the heads of the tank mounting screws) drill the holes 1/16 in. and enlarge to 5/32 in.


The vertical sides can be cut from Evergreen 40 thou x 250 thou strip, or from 40 thou sheet. Glue the sides and the base to the outside of the ends, and then measure and cut the angled side pieces, allowing extra to bevel the top, to fit tight against the vertical sides. Once everything has hardened, you can clean it up, and fill any obvious seams. Image showing dimensional detail for scratchbuilt B23-7 replacement fuel tank

Image showing dimensional detail for scratchbuilt B23-7 replacement fuel tank While the tank is drying, make 2 air reservoirs as per Figure 4. punch out 4 end caps from 40 thou styrene with the hole punch, and glue them to the 26mm lengths of 1/4 inch styrene tube.

While the air reservoirs are drying, punch two 1/4 in. holes in a piece of 40 thou styrene, allowing enough space to mark out for the air reservoir brackets as per Figure 3. Snap out the brackets, clean up and cut exactly in half to make 4 brackets. Cement these to the ends of the fuel tank, flush with the top and on 15mm centres. Image showing dimensional detail for scratchbuilt B23-7 replacement fuel tank

Image showing dimensional detail for scratchbuilt B23-7 replacement fuel tank Take the air reservoirs (when hardened), and round the ends either in a lathe or an electric drill using the mill file. Clean up with fine sandpaper, and drill No.76 holes in the ends for 20 thou brass wire plumbing. Glue these to the air reservoirs brackets and centred in respect to the fuel tank.

Drill two 3/32 in. holes in a piece of 40 thou styrene, and punch out 2 discs with the hole punch, centred on the 3/32 in. hole. Glue these to the inside of the bottom of the fuel tank, with the 3/32 in. hole centred in the 5/32 in. hole. Image showing dimensional detail for scratchbuilt B23-7 replacement fuel tank

Detail the outside of the fuel tank with as many fuel fillers, gauges, blank plates air filters etc, as you can find in photos, and plumb the air reservoirs with 20 thou brass wire. I also added a Detail Associates underframe mounted Bell (spaced off the tank with a small cube of styrene) to the front end, top right hand side of the fuel tank, although your prototype may have the (U Boat type) roof mounted Bell.

Prime with light grey paint, correct any faults then paint the colour of your prototype, weather with Oily/Grimy/Gloss blacks, fit the tank using the original screws, and enjoy....................RAP


B23-7 Info page

Home Steam Loco Index SP MoW Index Diesel Loco Index Diesel Roster Index
Freight Car Index Passenger Car Index Structure Index Depot Index
Feed Back Caboose Index DRGW Index Miscellaneous Freight Car Spec Sheets
Data Index PicIndex Diesel Model Info
website logo for use in banner exchange [185 x 50] (5k) This document prepared and maintained by Richard.A.Percy.
All Corrections, Additions and Flames should be aimed at Richard Percy espee@railfan.net
This document © 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008. Richard.A.Percy

Wednesday, June 10, 1998 8:22:02 AM