F3 vs. F7

[KeithL]

In looking through the many pages of K-Line's new catalog showing their F3 and F7 diesels, I noticed that there don't seem to be any differences between the two engines. I'm wondering, is it that K-Line's models don't show the differences, or were there no external differences between the prototype F3 and F7? Also, what were the internal differences?

Keith

[Buckeye Riveter]

Your answer can be found at:

http://www.burlingtonroute.com/rosters/droster/f7read.htm

I also think there may have been differences in horsepower due to improvments in the traction motors, but this really wouldn't affect the appearence of the engine, unless you were underneath looking up.

[lionelsoni]

They had the same engines and horsepower (1500). There seem to have been more differences within the two models than between them and many features of one model can be found on examples of the other.

[Anonymous]

If it helps here are a few specifications of the F3, from The Railroad Encyclopedia and The Great Book of Trains.

Length: A-unit 50ft 8in, B-unit 50ft
Distance between truck centers: 30ft
Truck wheelbase: 8ft 10in
Wheel Diameter: 40 in
Diesel engines: One 567B 16-cylinder pressure-charged 2-stroke Vee engine, rated at 1500hp
Transmission: D12 main generator, 4 D17 traction motors
Tractive effort: 57,500lbs
Maximum speed: between 50 and 120mph depending on which of eight gear ratios were fitted
Fuel capacity: 1500 gallons
Weight: 230,000lbs without steam generator
Max. axleload: 57, 500lbs

According to The Great Book of Trains, the difference between the F3 and F7 was primarily in the traction motors and electrical equipment, enabling 25% more load to be hauled up hills.

I hope this has helped--I'm really a steam fan, so I'm sure others can give you much more help.

See you around the forums,
Daniel

[FJ and G]

Keith,

Don't feel bad, I've been a train buff for almost 50 years and I still can't tell a lot of the diesels apart, esp. after they've been "shopped"

Dave Vergun

[Chris F]

According to "A Field Guide to Trains" by Gerald Foster, early F3's had 3 portholes and wire screening over the hood intakes. Later F3's and F7's had two portholes, a full-length grill over the high openings, and four sets of louvers between the portholes. Both K-Line's and Lionel's F3's appear to be the late F3/F7 versions.

[Anonymous]

K-Line Superchief



Model Railroader July 1998 p 36 has photos of 4 phases of F3s.

Phase I had 3 portholes.

Phase II and III had 2 portholes and 4 separate wire grills near the top of the shell. Phase I also had the 4 grills.

Phase IV has a long screen covering the 4 openings. The F7 also has the long screen. K-Line has the long screen.

A feature on the shell that distinguishes the F3 from the F7 is the dynamic brake openings. The F3 has 2 rectangular openings on the top of the shell behind the horns. The F7 has a fan similar to the radiator fans.

It appears the the K-Line F7 is actually a phase IV F3.

The Lionel F3 has the 4 separate grills, so it's a phase II or III F3.