by Allen Hazen
Something (something stupid and trivial) that I've long been curious about... The old Kalmbach Publishing "Diesel Spotter's Guide Update" has a photo (on page 5) of a switcher (off-brand, built by a locomotive company we try not to mention on this forum!) with two dissimilar trucks: one a conventional switcher truck, one a "Flexicoil." (The owning railroad had switchers with both kinds of trucks, and maintenace mix-or-matched.) Leading to the question of whether similar things ever happened with four-axle GE U or Dash-7 series locomotives.
Three different types of trucks were used with these units: the drop equalizer design used on Alcos from the 1940s on, often called "Type B" though this designation has no official status, GE's FB-2 truck introduced in the early 1970s, and the Blomberg truck (from trade-ins built by the unmentionable...). (The Alco "Hi-Ad," as on the majority of C-430, COULD have been used, and I regret that the New York Central's mechanical department never, in a spirit of experimentation, tried a truck exchange between a U30B and a C430, but apparently they never did.) Several railroads owned units with more than one type of truck, so maintenance forces COULD have been tempted....
We know the three types of truck are interchangeable, in the sense that a locomotive built with one type can be retrofitted with one of the others with no major modification of the underframe: GE, after getting a maintenance contract with Santa Fe in the ???late 1980s??? or ???1990s??? replaced the drop equalizer trucks the Santa Fe's B23-7 were built with (on at least soe units) with FB-2 (which are apparently easier to maintain. And when Conrail, desperate for locomotives early in its existence, bought the four U36B built but never delivered to Autotrain, GE, at CR's request, replaced the Blomberg trucks they originally sported with drop-equalizer trucks for uniformity with the rest of CR's 4-axle GE fleet. BUT...
QUESTION 1: is there any reason in principle (see question 3 below for a possibility) why one of these locomotives couldn't have operated with one sort of truck at one end and a different one at the other?
QUESTION 2: is there any photographic evidence that any of these locomotive ever were so re-trucked?
On a related matter... That other locomotive builder's GP-35 usually had Blomberg trucks, but some were built with drop equalizer trucks from Alco trade-ins. Apparently (going by the dimensions in drawings in a couple of 1990 issues of "Mainline Modeler") they were a half inch taller (14' 5" rail-head to roof versus 14' 4.5") with Blombergs than with drop equalizer trucks.
QUESTION 3: assuming this reflects a difference in the height of the truck center plate from the rail, is it enough to make it impossible to operate the locomotive safely with one of each kind of truck? Or could it be compensated for by putting some sort of liner in the "bowl" of the drop equalizer truck?
QUESTION 4: were GE units, like the U30B and U23B built for the Western Pacific and large numbers Seaboard Coast Line units, eqipped with Blombergs similarly a half inch taller than those with "standard" trucks? Or, when the Blomberg trucks were modified to accommodate GE's heftier traction motors, wasthe modified truck bolster that half inch lower?
(Well, I warned you that they were stupid trivia questions!)
Three different types of trucks were used with these units: the drop equalizer design used on Alcos from the 1940s on, often called "Type B" though this designation has no official status, GE's FB-2 truck introduced in the early 1970s, and the Blomberg truck (from trade-ins built by the unmentionable...). (The Alco "Hi-Ad," as on the majority of C-430, COULD have been used, and I regret that the New York Central's mechanical department never, in a spirit of experimentation, tried a truck exchange between a U30B and a C430, but apparently they never did.) Several railroads owned units with more than one type of truck, so maintenance forces COULD have been tempted....
We know the three types of truck are interchangeable, in the sense that a locomotive built with one type can be retrofitted with one of the others with no major modification of the underframe: GE, after getting a maintenance contract with Santa Fe in the ???late 1980s??? or ???1990s??? replaced the drop equalizer trucks the Santa Fe's B23-7 were built with (on at least soe units) with FB-2 (which are apparently easier to maintain. And when Conrail, desperate for locomotives early in its existence, bought the four U36B built but never delivered to Autotrain, GE, at CR's request, replaced the Blomberg trucks they originally sported with drop-equalizer trucks for uniformity with the rest of CR's 4-axle GE fleet. BUT...
QUESTION 1: is there any reason in principle (see question 3 below for a possibility) why one of these locomotives couldn't have operated with one sort of truck at one end and a different one at the other?
QUESTION 2: is there any photographic evidence that any of these locomotive ever were so re-trucked?
On a related matter... That other locomotive builder's GP-35 usually had Blomberg trucks, but some were built with drop equalizer trucks from Alco trade-ins. Apparently (going by the dimensions in drawings in a couple of 1990 issues of "Mainline Modeler") they were a half inch taller (14' 5" rail-head to roof versus 14' 4.5") with Blombergs than with drop equalizer trucks.
QUESTION 3: assuming this reflects a difference in the height of the truck center plate from the rail, is it enough to make it impossible to operate the locomotive safely with one of each kind of truck? Or could it be compensated for by putting some sort of liner in the "bowl" of the drop equalizer truck?
QUESTION 4: were GE units, like the U30B and U23B built for the Western Pacific and large numbers Seaboard Coast Line units, eqipped with Blombergs similarly a half inch taller than those with "standard" trucks? Or, when the Blomberg trucks were modified to accommodate GE's heftier traction motors, wasthe modified truck bolster that half inch lower?
(Well, I warned you that they were stupid trivia questions!)