Just wondering if I could swap shells from an unpowered FP7 onto a powered F7 B unit.
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I have the three rail version of the Canadian Pacific FP7 ABBA from a couple of years ago. You are correct in that the B unit is actually an F7B, not an FP7B. I don't believe that there were any FP7B units ever produced for the real railroads. Back to your question. I have both an unpowered CP F7B and a powered CP F7B. In a word, yes, the shells can be swapped(at least on mine everything lines up correctly). However, there will be one major issue to deal with(on mine there would be this issue-don't know about the latest runs of F7's). On my unpowered F7B shell, the shell body is one piece, with no removable roof hatch to gain access to the run/pgm, vol, and smoke switches. My powered F7B shell has a removeable roof hatch held on by small magnets that lets you access the various switches. So if you swap shells(if they're like mine) you will lose the easy access to the switches and have to remove the shell every time you need or want to change any of the switches. Unless you're a good surgeon and perform an operation on the roof of the unpowered shell.
I don't know if the newer runs have the shells done differently-maybe someone else here can chime in.
Nick
YES
Laidoffsick - thanks for confirming. Always enjoy your posts.
Machinist - Interesting, that's similar to what I just picked up. Mine are 2-rail. Canadian Pacific powered A and of course unpowered B. Didn't think about the switches. Smoke not a big deal on B unit (for me) and no run/program issue on DCC 2 rail.
There was never such a thing as an FP7 B unit.
Paws2k posted:Laidoffsick - thanks for confirming. Always enjoy your posts.
Machinist - Interesting, that's similar to what I just picked up. Mine are 2-rail. Canadian Pacific powered A and of course unpowered B. Didn't think about the switches. Smoke not a big deal on B unit (for me) and no run/program issue on DCC 2 rail.
I didn't even think about you having a 2 rail version-that probably works to your benefit in this situation. Back when these FP7's were produced, they were originally offered in an AB set, the powered FP7A and the unpowered F7B. You could also purchase a separate powered FP7A and those became difficult to locate after a short time. Eventually, owners of these engines pulling long heavy aluminum passenger trains, long freight trains or those with moderate to steep grades discovered that more power was needed to prevent the wheel slipping(especially if you only had the original AB pair). So when Scott at 3RD Rail announced the first run of F7 units, due to numerous requests, he also graciously agreed to produce powered F7B units for at least some of the roadnames that he previously had produced for the FP7's. I have no idea how many were made in 2R, 3R or exactly what roadnames were done. That is how I acquired my powered CP F7B unit. I originally had the AB set and then stumbled on another powered FP7A.
Nick
Very interesting. Just about the time I got back into O scale. Then I decided 2 rail was the way I wanted to go.
I have the PRR version of the Sunset FP7. The body on the FP units are longer than the F A & B units. Having not owned a sunset B unit, I'm not sure it's compatible. The wheelbase on the B unit is shorter.
have you measured any difference?
PRR Man posted:I have the PRR version of the Sunset FP7. The body on the FP units are longer than the F A & B units. Having not owned a sunset B unit, I'm not sure it's compatible. The wheelbase on the B unit is shorter.
have you measured any difference?
Don't know about the models but, EMD did NOT make any "FP7B" units. ONLY the "A Unit" was lengthened for passenger service in both the "7" and the "9" series, thus there were FP7A units as well as FP9A units, that were longer than a "standard F7A and/or F9A. The "B Units" were all the same length in the 3 series, 5 series, 7 series, and 9 series.
It is correct, the FP7Bs were the same body/length as the F7B. However, the Pennsy at least considered theirs to be FP7B according to the equipment diagrams. I don't know if EMD ccalled them FP7B or not.
prrjim posted:It is correct, the FP7Bs were the same body/length as the F7B. However, the Pennsy at least considered theirs to be FP7B according to the equipment diagrams. I don't know if EMD ccalled them FP7B or not.
No, EMD did not refer to them as "FP7B", only the FP7A and FP9A were so designated.
I purchased an extra powered ATSF F7B unit for the purpose of transplanting the powered drivetrain into my WP unpowered F7B unit. The silver paint is different on the 2 units, so I still need to repaint the fuel tanks as the powered unit has cutouts for the driveshaft as well as weights inside and must remain with the powered chassis. Sideframes were easy to swap. The steps however were mounted differently, as the ATSF units are body-mounted and the WP units were truck-mounted. Out came the drill and tap. Anyone need an ATSF dummy unit?
Don't know about the models but, EMD did NOT make any "FP7B" units
that's my point. if the OP wants to put the body of a FP unit onto the frame of a F unit, the body would be too long.
Well the OP said FP7B, but there is no such thing. The Sunset B units sold with the FP7A's are F7B's.... the same F7B's shell/frame that were sold with the run of F7s. So YES, he can swap B unit shells because they are ALL F7's 
Yep, Laidoffsick is correct as I have a F7 demo B unit I just dug out of storage from the 1st run. Looks to be the same length and same shell length and very similar detail-wise. Only diff is silver painted trucks with holed out center silver fuel tank for drive shafts.
Might just sell some other units and seek out another F7A or F7B powered ( Canadian Pacific). After all, sometimes it is the thrill of the hunt!
