(I will shortly post a related question, "PA-1 traction motors," to the Alco forum.)
The first Eries, at least, had the GE 746 model traction motors. (Railfan literature on the topic seems to agree on this; a trade-press article when the Eries were introduced that I have seen also specifies this model of t.m.) My question is: Did ALL Eries have these motors, or was a change (to 752?) made in the course of production.
Reason for asking: the contemporary Alco equivalent, the PA-1, seems to have been built with at least two, possibly three, different models of GE traction motors: 726, 746, 752. So...
Background: By the late 1940s, GE seems to have standardized on the 752 as its basic motor for large locomotives: Alco's, Baldwins and FMs after Westinghouse quit, GE's own U-series. Before that... Pre-war Alco Dl-109 had either 730 (for exclusively passenger service) or 726 (for dual service, as on the New Haven). According to a post to some Railroad.net forum a while back, the 752 was an upgraded and improved version of the 726 (fairly major upgrade, given the tractive efforts cited for 726 and 752 equipped Alco FA-1, though the upgrades made between 1950 and the 752AH used on GE's Dash-9 freighters without changing the model number are surely greater!). According to a "Trains" magazine article on FM locomotives from a few years back, one of the things that made it difficult for FM to compete was that they had chosen the 746 motor, which was more expensive (I think it had moreelaborate ventilation features). At a GUESS: in 1945, when the Erie was introduced as a dual-service use, suitable for heavy freight, FM decided they wanted something more robust than the 726, and the 746 was what GE could offer them, only later achieving comparable performance from a cheaper, 726-derived, model, the 752. BUT THAT'S JUST SPECULATION. Erie-built production lasted until 1949, after GE had started using the 752 on Alco-GE freight and passenger units. Hence my question: did some late Eries have the 752, or did they all get 746?
The first Eries, at least, had the GE 746 model traction motors. (Railfan literature on the topic seems to agree on this; a trade-press article when the Eries were introduced that I have seen also specifies this model of t.m.) My question is: Did ALL Eries have these motors, or was a change (to 752?) made in the course of production.
Reason for asking: the contemporary Alco equivalent, the PA-1, seems to have been built with at least two, possibly three, different models of GE traction motors: 726, 746, 752. So...
Background: By the late 1940s, GE seems to have standardized on the 752 as its basic motor for large locomotives: Alco's, Baldwins and FMs after Westinghouse quit, GE's own U-series. Before that... Pre-war Alco Dl-109 had either 730 (for exclusively passenger service) or 726 (for dual service, as on the New Haven). According to a post to some Railroad.net forum a while back, the 752 was an upgraded and improved version of the 726 (fairly major upgrade, given the tractive efforts cited for 726 and 752 equipped Alco FA-1, though the upgrades made between 1950 and the 752AH used on GE's Dash-9 freighters without changing the model number are surely greater!). According to a "Trains" magazine article on FM locomotives from a few years back, one of the things that made it difficult for FM to compete was that they had chosen the 746 motor, which was more expensive (I think it had moreelaborate ventilation features). At a GUESS: in 1945, when the Erie was introduced as a dual-service use, suitable for heavy freight, FM decided they wanted something more robust than the 726, and the 746 was what GE could offer them, only later achieving comparable performance from a cheaper, 726-derived, model, the 752. BUT THAT'S JUST SPECULATION. Erie-built production lasted until 1949, after GE had started using the 752 on Alco-GE freight and passenger units. Hence my question: did some late Eries have the 752, or did they all get 746?