Why did Alco PAs smoke like chimneys?

[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.

[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]

Why?

[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]

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.

[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]

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.

[CSSHEGEWISCH]

Turbo lag isn't exclusive to Alco 244's and 251's. Early GE FDL's had a similar problem. It can also happen on luxury automobiles although the smoke isn't quite as heavy. I remember seeing a Mercedes-Benz on I-294 leave a small cloud of smoke when he punched the accelerator while switching lanes.
EMD had a mechanical link to the turbo which cut out when the turbo finally kicked in on its own and this limited the smoking problem.
I've read that the Indian licensee for Alco has developed a new turbocharger which reduces the smoking problem. Imagine, an Alco that doesn't accelerate under a cloud of black smoke.

[Anonymous]

QUOTE: Originally posted by millerdc

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

Lemme guess: Independant locomotive power "expert" *** Dilworth rates the PA as 'most overated"?

I havent seen the 2004 issue, and I don't mean for this to sound disrespectfulll to you, but this just sounds so much like some of former EMD employee Dilworths ~independant~ expertise contributed to previous issues of the mag, I have to wonder.

[Anonymous]

Overrated? How dare they?[:(!] Being an Alco fan, this is almost enough to make me not want to read the January issue!!! But I still will to see all of the pictures of those wonderful Alco PA's. With a few others, almost all by Alco as well, the PA's were the best diesels of all time.

And back to your original question:
Firstly, great choice for a screen name! However, it's not just PA's that put out smoke like no tomorrow! I know first hand (and second [and third]) that the S-4s also put out a lot of smoke, and I think early RS's do as well. Viven los PA's de Alco!!! Long live the PA (which is definitely not overrated!!!).

Alco's forever,
Daniel

[AltonFan]

I haven't read the Trains article, so I can't comment on it.

On page 283 of Diesel Locomotive: the First 50 Years, the observation is made that "[U]ltimately 297 PA and PB units were constructed between June 1946 and May 1953, while EMD's postwar passenger unit sales totaled 1111 and continued until 1963." While the PAs were good-looking, photogenic, and rare, and thus inspired fan loyalty, apparently the PA's virtues were not apparent to railroad management. I would guess fans and motive power superintendents have different criteria for what makes a geat locomotive.

[kenneo]

EMD used a supercharger rather than a turbo charger on all 12-567 up to 1200 HP and 16-567 up to 1750 HP. After that, and on all 645's except the SW1500 (which is normally aspirated 12-645) they used turbos geared as mentioned in CSSHEGEWISCH note above.

American Locomotive Company put out some really great visual designs for locomotives, but the mechanics came close to being junk if they were not kept maintained. Where the EMD was a "low" upkeep design, ALCO was a "high" upkeep machine. Same problem for Baldwin, but about the time they got their act together (ALCO and Baldwin), it was too late since the RR's didn't want to take another chance on them when they had "reliable" EMD.

[jchnhtfd]

In terms of a fine product but poor factory support (lack of critical mass), the Fairbanks-Morse Trainmasters surely take the prize. The engine was unusual, but very reliable, and the things could pull like nothing else -- but if something went wrong, you were pretty well on your own, as the factory just couldn't (not wouldn't -- they were willing enough -- couldn't) help out much. That's really where EMD gained its edge and wound up on top.

[kenneo]

QUOTE: Originally posted by jchnhtfd

In terms of a fine product but poor factory support (lack of critical mass), the Fairbanks-Morse Trainmasters surely take the prize. The engine was unusual, but very reliable, and the things could pull like nothing else -- but if something went wrong, you were pretty well on your own, as the factory just couldn't (not wouldn't -- they were willing enough -- couldn't) help out much. That's really where EMD gained its edge and wound up on top.

[^] Absolutely correct.
Didn't help that the US Navy took all of their opposed piston motors for subs and some other crafts. Ruined the financial backing they needed to support their locomotives. They disappeared so fast because their motors were valued at twice the price of the locomotive plus removal costs for use as stationary engines.

Up through the E-6, EMD put a traveling mechanic-electrician on each train that had E-units pulling them so that if something went down, they were there to make it go again. They couldn't have done that without GM's money behind them.

As a side note, the SP was ready to invest heavly in FM's Trainmasters, but they had a problem that literally "deep-sixed them" - they would throw out burning hunks of carbon and still burning fuel. That's OK at sea, but not so in the forests. The folks along the ROW were not happy with having to put out all of the fires these engines started. Finally, one of the counties flat banned FM's of all types from operating in that county.

[adrianspeeder]

Turbo lag is one reason diesels smoke. When i'm pullin stumps or a heavy load at top rev with my diesel pickup, the turbo can't force enough air into the cylinders, so it smokes like a bunch of crack heads stuck in a police evidence room.
Another reason is the quality of fuel. I notice that if i put in cheap diesel, it is a little bit dirtier.

Adrianspeeder

[Anonymous]

As far as being overrated, I'm shocked Trains would say that (I havent picked up the issue yet, so I'm not sure exactly what it said). I once read that Trains magazine once deemed the Alco PA "an honorary steam locomotive" (not because of the smoke, but because of how great and popular they were).

[Anonymous]

Holy molly.. Now I look like an idiot because i thought that was an EMD E series on the front cover..

No matter, Even I must admit that cover is pretty much a bold statement... I wonder whos bright idea that was...

[Anonymous]

PA's rule!! I love em. I grew up on Long Island and my earliest train memories were of the Big PA's. I would go with my mom to pick up dad at the station (Port Jeff – end-of-line) and the PA’s would be sitting in the dark cold idling to stay warm.

[dharmon]

So if I read this thread right, the REAL reason that ALCOs died was lung cancer??

[dharmon]

QUOTE: Originally posted by kenneo
[[^] Absolutely correct.
Didn't help that the US Navy took all of their opposed piston motors for subs and some other crafts. Ruined the financial backing they needed to support their locomotives. They disappeared so fast because their motors were valued at twice the price of the locomotive plus removal costs for use as stationary engines.

Up through the E-6, EMD put a traveling mechanic-electrician on each train that had E-units pulling them so that if something went down, they were there to make it go again. They couldn't have done that without GM's money behind them.

As a side note, the SP was ready to invest heavly in FM's Trainmasters, but they had a problem that literally "deep-sixed them" - they would throw out burning hunks of carbon and still burning fuel. That's OK at sea, but not so in the forests. The folks along the ROW were not happy with having to put out all of the fires these engines started. Finally, one of the counties flat banned FM's of all types from operating in that county.

I mentioned before in an earlier thread that the Navy uses EMD 567s and 645s in aircraft carriers as standby generators. They use a compressed air starter, operated an electrically closed valve. If power fails, the valve opens and starts the generator. They, fortunately aren't used too much in this manner, but they are tested periodically. It never failed though, I'd be on the bridge and the engineers would call up and tell us they were going to start a diesel for maintenance........two minutes later, almost on que the bridge phones would start ringing with reports of smoke from all over the ship.....

[Anonymous]

Turbo lag was the main reason for the smoke, also most early turbos were belt driven, so if you knocked the throttle right into the 4th or 5th notch, you were garunteed to have belt slippage. Thereforethe turbo does not accelerate as quickly as the engine itself, so it cannot force enough air into the cylinder fast enough. It ends up with there being a higher fuel to air ratio in the cylinder, and with more fuel, more exaust is created. Another interesting fact ALCo PA's (at least the D&H ones) had 3 different prime movers in their life; built with a 16-244, rebuilt with a 16-251C and later had a 12-251C installed.[:)][:D][8D]

[Anonymous]

hahahahahaahhahah

Lung Cancer!!

Hahahahahahahaha

Dan, your hilarious!

[:D]

I guess the pictures on the carton weren't sufficent enough!!

[:D]

[highballer1]

I ran Alco RS3's on the old Spokane, Portland & Seattle Ry. , back in the 70's. They were all notorious for belching out heavy smoke, especially when you threw it into forward, let the air off and cracked the throttle beyond notch 3 or 4. Part of the problem was the lack of "catch - up" by the turbos and the amplidyne exciter circuit built into the throttle-mechanical-electrical hookup. Both of those contributed to the belching. I always enjoyed the fact that when you saw the smoke roll, you knew immediately you were going to get results!!

[Anonymous]

One more factor no one has touched on yet: Diesels will gladly swallow a very rich mixture without missing a beat..you get more power for the price of a black sooty exhaust; and remember, diesel fuel was very cheap 30 years ago!!

[JoeUmp]

So who supplied the diesel fuel for these things, Wal-Mart?

[Anonymous]

I can't say wy they smoked heavily, but I do know that the Rio Grande droped them from the CZ because of engine failure.

[BodieBailey]

Maybe I'm off base,but I think the Alcos were 4strokes and idled very slowly. They came up to speed slower and did not burn as effecently as the other 2 strokes. If you ever listen to the Alcos idle you would think the were going to stall out.

My two cents Bodie Bailey

[CSSHEGEWISCH]

Alco 244's & 251's and GE FDL's are all 4-cycle engines. FM OP's and EMD 567's, 645's and 710's are two-cycle engines. I'm not sure about De La Vergne (BLW) or Hamilton engines.
EMD diesels, being 2-cycle, required a Roots blower to force air into the cylinders if they were not equipped with a turbocharger.
A turbocharger is a good way to get extra horsepower out of a given design, but it is a high-maintenance item and this may be why EMD avoided turbochargers until Union Pacific forced the issue in the late 1950's.

[jchnhtfd]

Provided the engineers did their homework, there is no reason why a four stroke diesel and a two stroke diesel should differ significantly in efficiency. As Css... said, two strokes must have either a blower (which may or may not be a supercharger -- there is a difference) or a turbocharger, while four strokes don't need one.

Idle speed and maximum power/torque speeds are engineering choices in the design of the engine although, in general, bigger (heavier) engines run more slowly than littler (lighter) ones. The extreme, of course, comes in marine diesels, which may have a maximum rpm on the order to 300 rpm and idle at the count the bangs speed!

[CJBeard]

I was told by a Alco fan that California banned Also's because of the smoke.