I’ve read a few articles and searched the web, but can’t seem to find the answer…
Can you tell me which GE U-boats featured naturally aspirated engines (non turbo)?
All of GE’s line of Universal diesel locomotives were turbo charged 4 cycle engines. There were no nonturbo production locomotives.
Oh, ok
and what about Baldwin and Alco? Did they have high-power (say around 1500-2000hp) non-turbo engines in read switchers?
For their day, I suppose you could consider 1500 and 2000 to be high horsepower numbers. All of Alco’s locomotives, no matter what the hp were turbo charged. Baldwin made non turbo switchers but I cannot think of any nonturbo road switchers in the Baldwin line.
The Baldwin 608NA produced 1,000 hp (traction) from 8 normally aspirated cylinders. That was the best available from a Baldwin normally-aspirated engine. Paired in a one-off DT-6-6-2000 for EJ&E, 2000 hp was produced in a locomotive. In effect this was a road-switcher.
S. Hadid
ALCO’s line of low horsepower switchers did not have turbochargers. None of the box cab models had turbocharger. For hood switchers this is true back to the first ones built in 1931. ALCO pioneered turbocharging in the US with the installation of the Buchi turbocharger in the HH900 starting in 1937. The low horsepower engines of the 531, 538, and 539 engines were not turbocharged. This would include the HH300, 0900, HH600, HH660, S-1, S-3, and S-11 models.
Data from The Second Diesel Spotter’s Guide and ALCO A Centennial Rembrance.
thanks, so then, I guess, EMD roots blown engines were the only “high power” engines which had their exhaust go directly from the cylinders to the stacks
I’m not from US, so I have to ask, do old GE and Alco engines also develop such piercing noise, or does the turbo muffle the sound?
I’m thinking the Cooper Bessemer GE’s were not turbocharged.
Randy is correct, a number of the smaller CB engines were not turbocharged. DSG II concurs see page GE-138.
Don’t forget the FM opposed piston engines - 2400HP in the TrainMasters.
The turbos generally muffle the exhaust note, though the U-series GE’s had a pronounced chugging sound when working hard. The turbos on Alco 539’s also added a distinctive whine.
If I understand the question, do old GE and Alco 4-stroke turbo diesels produce the piercing scream of the EMD 2-stroke turbo diesels? If that is the question, then as now, the answer is no, except when the exhaust drives it.
The reason you always hear the turbo on an EMD is because at lower throttle notches, the impeller shaft is driven by the engine through gearing and via overrun clutch, and the turbo unit functions as a de-facto centrifugal blower until exhaust gas pressure is sufficient to drive the turbo unaided by the engine drive itself. This occurs around throttle 5-6.
The reason for the mechanical drive is due to the 2-stroke design of the engine. It cannot breathe on its own, so it must be pressure-fed air in order to run. Once the engine is running at a high enough speed, the turbo is exhaust driven and this helps to create more power from the engine over a Roots type blower (the Roots blower itself consumes power, while the turbo uses ‘free power’, otherwise wasted heat energy to operate). Below the turbo threshold speed, the impeller must be mechanically driven in order to properly scavenge the cylinders.
No, I ment blower scavenged models…
Their exhaust note is much clearer than that of turbocharged units, they produce a sharp percussive sound from the stacks
I ment, if GE and Alco units also have such strong exhaust note