Chuck and Hol,
Chuck, your photos were taken in May and June of 1965 which is about the time that the 790 series cab gallery cars were introduced. Practices were changing at that time. In general, the power car was on the west end, but for the short mid day trains, it was probably not considered as important. There were, only five or six 7200 series power cars, which had been rebuilt from the old 7000 series open platform cars. All of the rest of the power cars in the 7300 series were rebuilt from 6100 series six wheel truck main line passenger cars; two combines and the rest were full coaches. I don't know for certain, but I believe the gen sets in the 7200 cars may have been smaller (lighter) and maybe less obnoxious? In any case, on a two car train, whether the power car was in front of or behind the other gallery car, probably didn't make much difference in terms of smoke and fumes that the few mid day passengers would encounter in Union Station.
The E8s and E9s were set up so that they could power mid day two car commuter trains without the use of a head end power car. The 74 volt DC auxiliary generators on the locomotives had sufficient power to handle the cars. Here is a link that provides a typical example.
As for E7s on commuter trains, after the arrival of the E8s and later E9s, the E7s were seldom use in commuter service except occasionally on smaller trains as shown in Chuck's photos. The E7s, of course, were used in commuter service in the late 40s and early 50s, but as more E8s were delivered, they were preferred because they accelerated the longer heavier trains better and, therefore, could maintain the schedules more effectively. While the E8s and later, the E9s had a little more horsepower, that was only part of the story. The E7s were equipped with a 52:25 gear ratio which permitted 117 mph operation, but decreased low speed performance (like trying to start a automobile in 2nd or 3rd gear). (The 52:25 GR had a minimum continuous speed of only 40 mph. Some Q E7s were later converted to 55:22 GR which provided a max. speed of 97 mph.) TheQ E8s and E9s, on the other hand, were originally equipped with 55:22 GR originally which had a maximum speed of 98 mph and minimum continuous speed of 30 mph on the E8 and 33 mph on the E9. Some Q E8s were later re equipped with 57:20 GR that reduced the maximum speed to 85 mph and lower the min. cont. speed to 26 mph.
The lower GRs on the E8s and E9s and the minor increase in HP, gave them a better ability to quickly accelerate the full nine car commuter trains. I doubt that an E7, particularly with the 52:25 GR could maintain the schedule with a full size rush hour train.
Bill Barber
Gravois Mills, MO
Fri Mar 1, 2013 12:10 pm (PST) . Posted by:
Fri Mar 1, 2013 2:49 pm (PST) . Posted by:
Isn't it pretty unusual to see E7s in suburban service, too? As a far Lines West guy, I've always thought the E7s were not regularly used on suburban trains.
Hol
To:
CBQ@yahoogroups.comFrom:
czeiler@centurytel.netDate: Fri, 1 Mar 2013 17:33:42 +0000
Subject: [CBQ] Power Car On East End On Dinky
Hello, I have posted a couple photos at another site that show the power cars on the east end of a Dinky. This is somewhat unusual as the power cars were typically on the west end, presumably to keep the noise and fumes away from boarding passengers in Union Station. The question is: Why were the power cars turned around? If this question has already been answered, please direct me to that answer, thanks.
Photo 1
Photo 2
Photo 3