CRI&P Diesel 4151

[lecheminot]

According to the online Diesel Shop's Rock Island Diesel Locomotive Roster F9am's are numbered in the 4151 series. I have a slide of a F unit 4151 numbered which looks more like a F3 with the "chicken wire" where on a F9 there should be stainless steel grill work. The picture was taken in Dec 1972. Did perchance the Rock Island run F9's without the grill work???
Many Thanks to anyone who help on this query

[westr]

The F9Am's came from Union Pacific and are former F3s. Union Pacific had their F3s rebuilt to F9 specs in the late 50s, but many of the F3 spotting features remained. When UP and Rock Island were trying to merge, some of these were sold to Rock Island in 1972 in exchange for old Rock Island units, which were used as trade-ins for new UP SD40-2s. CRIP 4151 was previously UP 507. Don Strack's Utah Rails has more information: See http://www.utahrails.net/all-time/all-t ... hp#f9a-500 and http://utahrails.net/up/union-pacific_f9-or-f9m.php.

Several pictures of these rebuilt F-units in the 60's, including UP 507, are at: http://railsnorthwest.com/mcnwr/upvintage.html