Why did Alco PAs smoke like chimneys?

[Anonymous]

fascinating--a rich mixture. just like my 318 when the carb. floods!

sounds like Alco wasn't exactly ahead of the pack on their motor engineering--but aesthetically they certainly came up aces. The distinctive, graceful and powerful-looking design in just unbeatable.

[jchnhtfd]

The Alcos of the day used one of two engines -- the '244' and the '251'. Both of them were turbocharged. In those days (sounds like ancient history here!) fuel controls on diesels weren't as sophisticated as they became later -- even a few years later. The only way to get a diesel to accelerate is to feed it more fuel. When you tried to accelerate and Alco -- either engine -- the fuel mixture went 'way rich until the turbo, which was a big heavy puppy (EMD's, for instance, were and are a lot lighter), came up to speed and started really pumping air, which took a while. That rich mixture is what made the smoke. Built into the early engines.

But quite distinctive...

[Anonymous]

I love PA's! I can't see how they're overrated. There must be something good about them for them to be as immensly popular as they are. I certainly agree with you that D&H PA's are better than the Turbotrain any day. I was born far too late to see Alcos operating on the railroads, but it seems that most Alcos smoked lots, not just the PA's.

[espeefoamer]

The Jan.issue of Trains hasn't reached out here yet.I am desperate to read it. My first train ride was behind PA's,on the San Joaquin Daylight,in 1961,when I was 9 years old.I didn't know what they were at the time,but fortunately my grandfather took movies.We had an A_B_A set. The PA's smoked because the turbocharger lagged behind the acceleration of the engine.We also had a 3/4 dome and a diner.(The Automats weren't built until the following year.)[8D][:D][:p][:)

[Anonymous]

Why?

[millerdc]

Look in the current (JAN 04) issue of Trains and they rank the Alco PA as the most overrated engine of all time.

[Anonymous]

I was born too late to see many PAs in action, but when I was nine and living in the Northeast Kingdom of Vermont my dad took me over to Plattsburgh where we caught the D&H's Adirondack down to Grand Central (It was the summer of 1976, I believe--I remember my disappointment the next year when we rode the new turbo train).

When those blue and silver PAs rolled into the station I was in total awe--it was the most beautiful train I'd ever seen in my life. Anyway, we headed right for the vista dome car, which was one car back from the locomotives. And I remember being struck by how much smoke came out of those bad boys.

Since then I've read that PAs were notorious for belching black smoke. Why was that? I realize they had some monster diesel motors inside, buy why so smoky?

I was kind of hoping I'd get lucky and somebody on this forum might have operated or maintained PAs in their career. Were they prone to breakdowns and fussy mechanically?

Just curious--thanks. And if anybody here remembers the Adirondack and maybe has some photos, I'd love to see them! (there's a few in "A Decade of D&H" but not much). I didn't start taking serious train pictures until the next year.