I acquired a B&O 633 with sintered metal trucks and operating knuckle couplers (not the split-rivet conversions.). The David Doyle book shows these only came with the stamped metal trucks and link couplers. It is red plastic, not painted. The frame is die-cast and I can’t find any signs that it was tampered with or replaced. Does anyone know if Flyer produced 633 with this truck/coupler assembly?
Assuming the refrence material is correct, then I would suspect that what simply happened was that at some point in the past someone put the B&O shell on a newer car’s frame. That would be the easiest way to effect the conversion.
Whether or not it was modified, I would not rely on Doyle as an authority.
The 633 B&O is strictly a Stamp Link Coupler Truck. Basically all 600 series cars came with Stamped sheet metal trucks. 800 and 900 series cars came with the sintered iron trucks with knuckle couplers. I also have a car where the frame was switch but mine was from the sintered to the stamped trucks. I just use it as a conversion car with a knuckle on one end and a link coupler on the other.
Most likely someone put these trucks on your 633 car. You said it had a die-cast base. Check to see if the Gilbert name is on it If not it probably isn’t a Gilbert base. Gilbert switched to stamped sheet metal bases before switching to knuckle coupler trucks so if it’s a Gilbert base, it should be a link coupler car. Perhaps a trained Gilbert service man put the trucks on.
However Gilbert was known for using up old stock at times so you never know. I have a K5206W set in its set box with a K325 Hudson, 929 stock car, 926 tank car and 930 red caboose but a 640 gray hopper with what appears to be factory installed knuckle coupler trucks. So I wouldn’t assume anything unless it was examined by an expert.
Thanks to everyone who has replied. I had not used this forum before and enjoy hearing the feedback on the B&O boxcar. I should have remembered the 600 v. 900 series differences regarding trucks and couplers. I’m just “re-discovering” AF after a 40-year absence. As you’ve said, it’s either an excellent conversion or a factory anomaly.