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The Alco PAs and a lot of other Alcos of that era, were powered by the Alco 244 prime mover, released in 1944. It was used in a lot of Alco diesels and while it was not as good as the EMD design of the era, I think it's a bit of a stretch to call it a "lemon." Thousands of 244's served long and well for many years in Alco products. There are still a handful of them running today. In 1951, Alco came out with their 251 prime mover, which was a MUCH better design than the old 244.

One of the 244's problems, and the problem which caused all the smoke, was "turbo lag." Like most turbos, the Alco turbocharger was driven solely by the exhaust gas stream. When the throttle was notched up quickly, the governor and fuel rack instantly delivered the higher fuel delivery rate called for by the higher throttle position, but the turbo was not spinning fast enough to deliver enough air to properly burn all the fuel. The turbo would "lag" the throttle change by several seconds as it spooled up. It was during this time that the Alco 244 could deliver prodigious amounts of smoke!

By contrast, the EMD 567 diesel of that era did not suffer from this problem because it had a different design. Because the EMD diesel was a 2-cycle design, all of them were supercharged via a gear-driven Roots blower. However, in the turbo models, the turbocharger was also gear driven! In throttle positions 1 through 5, the gear driven turbo kept pace with the fuel delivery and didn't lag a throttle position change. In an ingenious bit of design work, the turbo was driven through those gears via an over-running clutch. Once the throttle hit Run 6 and above, the exhaust gas stream could spin the turbo faster than the gear train could, and the over-running clutch allowed that to happen. This is why you don't see turbo lag smoke from an EMD...even an old EMD.

Rich Melvin posted:

The Alco PAs and a lot of other Alcos of that era, were powered by the Alco 244 prime mover, released in 1944. It was used in a lot of Alco diesels and while it was not as good as the EMD design of the era, I think it's a bit of a stretch to call it a "lemon." Thousands of 244's served long and well for many years in Alco products. There are still a handful of them running today. In 1951, Alco came out with their 251 prime mover, which was a MUCH better design than the old 244.

One of the 244's problems, and the problem which caused all the smoke, was "turbo lag." Like most turbos, the Alco turbocharger was driven solely by the exhaust gas stream. When the throttle was notched up quickly, the governor and fuel rack instantly delivered the higher fuel delivery rate called for by the higher throttle position, but the turbo was not spinning fast enough to deliver enough air to properly burn all the fuel. The turbo would "lag" the throttle change by several seconds as it spooled up. It was during this time that the Alco 244 could deliver prodigious amounts of smoke

Yes - and one of the things I prefer about Alco P's and F's vis-a-vis EMD E's and F's (besides the better looks of the Alcos) is the sound. An Alco 4-cycle prime mover has an almost casual, "Relax - I got this" sound about it, as compared to the EMD 2-cycle "all wound up" sound.

Of course, all that I just typed is irrelevant, purely foamer rail fan talk -  but it's fun.

Me - I tend to prefer my locos with 2 or 3 or 4 (or 6!) cylinders and a big horizontal boiler on top, anyway.

scale rail posted:

What I have been told from old steam guys, is they weren't called "honorary steam engines" because they smoked so much but because they looked so good. Nothing like the everyday GM or other models of the day. Donsp alco

You gave me a framed copy of this photo for my birthday one year.  It's hanging in our spare bedroom.  Matt

Rich Melvin posted:

The Alco PAs and a lot of other Alcos of that era, were powered by the Alco 244 prime mover, released in 1944. It was used in a lot of Alco diesels and while it was not as good as the EMD design of the era, I think it's a bit of a stretch to call it a "lemon." Thousands of 244's served long and well for many years in Alco products.

Thank you, Rich.  Railfans need to hear factual information about the 244.

Those who actually experienced 244-powered Alco-GE locomotives in service on Class I railroads saw them working hard and reliably, on the roads which gave them good maintenance.  Santa Fe's PA1/PB1 "lemons" pulled trains on a 2200 mile route at 100 MPH (later 90 MPH), for over 20 years, with very few road failures.  Southern Pacific assigned its Alco-GE passenger "lemons" to its routes with the worst mountain grades.  Spokane, Portland & Seattle, as well as Delaware & Hudson, successfully relied on their fleets of "lemons" powered by the Alco 244 diesel engine.  

The self-appointed Alco experts got their (mis)information from reading, not from experience.  Authoritative writing which is critical of Alco-GE 244-powered locomotives and backed up with numbers, is not to be found.  The early turbocharger and crankshaft issues certainly happened, but were successfully addressed by 1950, and thereafter, Alco-GE's were capable of reliable service.

True, the maintenance costs were higher, but much of the maintenance was for small things such as oil leaks, and more shop time was required to perform many of the same maintenance tasks that could be done in a shorter time on  EMDs.  The EMD diesel engine was in a class by itself, but that does not make the Alco 244 a pariah.

The splendid, but complex, General Electric Amplidyne excitation system was responsible for much of the heavy smoke.  Alco-GE's with well-tuned Amplidyne equipment typically emitted only moderate smoke.

Back to the actual topic of the thread:  Lionel's Legacy PA's can certainly smoke.  It's impressive.

 

Last edited by Number 90

Lack of maintenance causes many more problems in the long run. Accountants who know nothing of how machines work like to save short term money by deferring maintenance, but that never works in the long term.

I used to repair machines for the semiconductor industry that were very fussy and maintenance intensive, and most customers gave them little attention until they broke down. Some customers maintained them regularly and theirs hardly ever broke down.

It's a lot about how well you know and care for your machine.

Last edited by RoyBoy
Rich Melvin posted:

The Alco PAs and a lot of other Alcos of that era, were powered by the Alco 244 prime mover, released in 1944. It was used in a lot of Alco diesels and while it was not as good as the EMD design of the era, I think it's a bit of a stretch to call it a "lemon." Thousands of 244's served long and well for many years in Alco products. There are still a handful of them running today. In 1951, Alco came out with their 251 prime mover, which was a MUCH better design than the old 244.

One of the 244's problems, and the problem which caused all the smoke, was "turbo lag." Like most turbos, the Alco turbocharger was driven solely by the exhaust gas stream. When the throttle was notched up quickly, the governor and fuel rack instantly delivered the higher fuel delivery rate called for by the higher throttle position, but the turbo was not spinning fast enough to deliver enough air to properly burn all the fuel. The turbo would "lag" the throttle change by several seconds as it spooled up. It was during this time that the Alco 244 could deliver prodigious amounts of smoke!

By contrast, the EMD 567 diesel of that era did not suffer from this problem because it had a different design. Because the EMD diesel was a 2-cycle design, all of them were supercharged via a gear-driven Roots blower. However, in the turbo models, the turbocharger was also gear driven! In throttle positions 1 through 5, the gear driven turbo kept pace with the fuel delivery and didn't lag a throttle position change. In an ingenious bit of design work, the turbo was driven through those gears via an over-running clutch. Once the throttle hit Run 6 and above, the exhaust gas stream could spin the turbo faster than the gear train could, and the over-running clutch allowed that to happen. This is why you don't see turbo lag smoke from an EMD...even an old EMD.

Excellent description.  To me the coolest things about the EMD's is the fact that they utilize a fabricated engine block and that the pistons are not offset like in a normal vee engine.  They use what some call a knife and fork or basket where one rod does not have a full journal, something that will work only because it is a two stroke. Anyone who ever ventured through the plant at LaGrange and strolled down the block assembly line sure got to see some neat stuff, those are surely some of my fond memories from a short time working for EMD.

In 1970, I was working the afternoon outside hostler helper job at San Bernardino.  The Roundhouse Foreman sent the Hostler, the Herder and me down to the X Yard, across from the depot, to pick up an Alco RSD15 ("alligator") that had been set out by a through train, and bring it to the house.

Santa Fe had built a small, elevated, yard office, next to the Mount Vernon viaduct, enabling the Yardmaster to see engines at both ends of the yard.  We had to go right past this structure with the engine.  We debated whether we should do it, but the temptation was too great.  We idled up next to the little office, fully applied the brakes, put the reverse lever in neutral and brought the throttle out to Run-8 for about ten seconds.  Oily, black, Alco exhaust boiled up and into the office through its open windows, and, as we left the scene, "Uncle Bob" Wade, the afternoon Yardmaster was coming down the stairs.

When we got to the house, the Foreman was suppressing laughter.  "Wade says you ruined his white shirt.  You better get down there and make amends."  We drove over and talked with Bob, who was beginning to be a good sport about it.  He declined our offer to buy him a new shirt, and we never heard another word about it.

Last edited by Number 90
Number 90 posted:

In 1970, I was working the afternoon outside hostler helper job at San Bernardino.  The Roundhouse Foreman sent the Hostler, the Herder and me down to the X Yard, across from the depot, to pick up an Alco RSD15 ("alligator") that had been set out by a through train, and bring it to the house.

Santa Fe had built a small, elevated, yard office, next to the Mount Vernon viaduct, enabling the Yardmaster to see engines at both ends of the yard.  We had to go right past this structure with the engine.  We debated whether we should do it, but the temptation was too great.  We idled up next to the little office, fully applied the brakes, put the reverse lever in neutral and brought the throttle out to Run-8 for about ten seconds.  Oily, black, Alco exhaust boiled up and into the office through its open windows, and, as we left the scene, "Uncle Bob" Wade, the afternoon Yardmaster was coming down the stairs.

When we got to the house, the Foreman was suppressing laughter.  "Wade says you ruined his white shirt.  You better get down there and make amends."  We drove over and talked with Bob, who was beginning to be a good sport about it.  He declined our offer to buy him a new shirt, and we never heard another word about it.

I love first hand accounts like this.

That kind of story deserves a write up in Classic Trains magazine, or maybe OGR would like it.

Number 90 posted:

In 1970, I was working the afternoon outside hostler helper job at San Bernardino.  The Roundhouse Foreman sent the Hostler, the Herder and me down to the X Yard, across from the depot, to pick up an Alco RSD15 ("alligator") that had been set out by a through train, and bring it to the house.

Santa Fe had built a small, elevated, yard office, next to the Mount Vernon viaduct, enabling the Yardmaster to see engines at both ends of the yard.  We had to go right past this structure with the engine.  We debated whether we should do it, but the temptation was too great.  We idled up next to the little office, fully applied the brakes, put the reverse lever in neutral and brought the throttle out to Run-8 for about ten seconds.  Oily, black, Alco exhaust boiled up and into the office through its open windows, and, as we left the scene, "Uncle Bob" Wade, the afternoon Yardmaster was coming down the stairs.

When we got to the house, the Foreman was suppressing laughter.  "Wade says you ruined his white shirt.  You better get down there and make amends."  We drove over and talked with Bob, who was beginning to be a good sport about it.  He declined our offer to buy him a new shirt, and we never heard another word about it.

His shirt? -Hell, you probably coated his lungs pretty good also...

@Norton posted:

Same with FAs.

Pete

Byoootiffic! I'm not down with diesel smoke units - if companies had figured out how to make it look more like exhaust than blown engine heads, I'd be totally onside. But this short vid photo is very cool and would love to see more of your layout, regardless what stage it's in. Just seeing your powered units rounding that bend is very RR!

 

@JamesRx posted:

Love the photo RSJB! Still waiting for Lionel to figure out how to make the smoke black!

I think a lot of folks know "how" to make black smoke, the real question is, do you want to live with the consequences!  Black smoke contains particulate matter, it will quickly make your whole train room and layout a black mess!  What do you think all that grime on locomotives is?  You guessed it, particulate matter from the black smoke!

I think a lot of folks know "how" to make black smoke, the real question is, do you want to live with the consequences!  Black smoke contains particulate matter, it will quickly make your whole train room and layout a black mess!  What do you think all that grime on locomotives is?  You guessed it, particulate matter from the black smoke!

Smoke as it stands now is a particulate. Specifically a condensate. The heating chamber vaporizes an oil into a gas, which will is clear, which then cools as the gas leaves the stack and condenses into oil droplet "smoke" observed. Similar to water steam. Thus, one is still breathing in a particulate. The particulates are liquid condensed oil droplets rather than something like a solid ash. The oil is colorless and so the smoke is colorless. Black oil is oil with dispersed carbon particulates. In concept, if designed correctly, one could use water as smoke fluid as it would be the same chemical phase transition and would give the same visual appearance that we see now with oil. 

The black smoke that is observed leaving from either diesel or steam locomotive exhaust ports is mainly uncombusted carbon. Thus, black smoke is an indication of inefficient operation as that carbon should be used in the combustion process produce energy to propel the locomotive. Particulate carbon would be far worse to breath and get into the lungs and and as stated would make much more of a mess to the layout than the current technology.  

Very nice.

I love NYC PA's

You know what would even make that more complete, back in 1998 Lionel made a PB1, now it wouldn't have smoke but I bet someone could figure a way to add it to it. 6-18966 

I have three sets of the original TMCC PA1/PB1's I love them. I have an A-B-A on the shelf with a long line of passenger cars behind it. 

Last edited by rtraincollector

I have a 2-rail MTH SD9 with smoke.   It put out a prodigious white cloud.  Two sessions of that, and I became nauseous.  And my test loop is pretty much in an open porch with a breeze.  I shall forego the smoke.

I am not super sensitive - I love to go to Chama and get cinders in my hair and a snootful of real coal smoke.

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