The Minnesota Zephyr goes behind the house I live in. Sunday it started several fires along the tracks that I helped put out. This isn’t that uncommon of an occurance in the dry parts of the summer. People working for a track contractor said the sparks were coming from the exhaust. Can a spark arrestor be installed on the exhaust. I like to see the train go behind the house I’m in, but I don’t want a fire to burn up the house.
Installing a spark arrestor is the beginning. After that it has to be maintained and kept clean. If this is done the spark arrestor is quite effective. This is a big problem with EMD roots blown engines. Since we switched to GE locomotives we have not had any problems with ROW fires.
Randy
Randy: EMD roots blown engines…want to put that in English?
Mook
I assume a Roots blower on a train is made by the same folks who make Roots blowers for cars. True?
m
Same design, just a little bigger than the 8-71 GMC blower sitting on your Chrysler Hemi. [}:)][}:)] It just has a different purpose sitting on a 2-stroke diesel (moving air) than on a gasoline engine (pressurize air for more power!!).
Randy
I thought so. Now if I just had a hemi…
Actually I have a Mustang gt with a chip in it and that’s all I’ll ever be able to handle. I’m sure I’d do myself in quick with a supercharged Hemi.
m
Randy:
The blower on a Diesel has exactly the same purpose as it does on a gasoline engine. The only difference is that it is more effective on a diesel due to the relatively slow motion of the engine (1000 vs 6 to 8,000 rpm). Headers on a gasoline engine can greatly increase the horsepower output , but only on a racetrack where the noise poses no problem. A supercharger is the only way you can increase the power of a diesel without generating objectionable noise levels and also avoiding operating at higher rpms. An automobile engine can operate at higher rpms to develop more horsepower because the reciprocating components are relatively light. The High compression ratios of diesels dictate that all components be heavy and thus unable to operate at higher rpms to generate more horsepower. The supercharger enables the diesel engine to develop more power because it forces more air into the cylinders. It has the same effect on gas engines. The only difference is that there are other ways that you can soup up a gasoline without resorting to supercharging.
There is a fuel additive some railroads specify in the summer to reduce sparks from the engine. It does not seem to be 100% effective so some roads may opt not to spend the money for it.
As to pressurizing the locomotive intake air. Gasoline engines in automobiles are four stroke exclusively since the old Saabs. Tne EMD diesels have historically been two cycle engines. They need a blower of some sort to blow the exhaust gasses out of the cylinders. Though the Roots system does supercharge the engine that is not the primary purose. When an EMD has a turbo charger it is gear driven to blow out the exhaust until the higher engine rpms where exhaust gasses take over to drive it. This has been discussed over and over on this forum and others. It should show up in the search function.
There are mufflers for EMD engines which contain more effective baffles. These were fitted to EMD units in New South Wales in 1980 after a dry summer and complaints from farmers. Ours were made by Farr, I think. All EMD blower engines have cylindrical mufflers immediately above the engine. The modified versions looked the same but had different internal baffles that were more effective as spark arrestors. They also reduced the sharp exhaust beat of the EMD locomotives, sadly. The new mufflers had differently spaced stacks, so you could always tell which units were modified.
Peter
No, sorry but thats not right. The supercharger on a 2stroke emd is there for exhaust scavenging and I think only makes 1-2lbs of boost. Compleatly different animal than a gasser.
Turbos are on diesel are used waaaay more often than superchargers for boosting purposes. (I know, I have one…) In fact, I cant think of a diesel engine right now that doesn’t use a turbo and uses a supercharger instead.
RPMs are lots less on a diesel engine vs. a gasser, as there is no need for rpms for power. Heck, I make more torque at idle in my PSD than my ole 302 does at top it its torque curve. And the peak of the torque curve is around only 1300rpm for me on the diesel.
There are lots of ways to hop up a diesel engine other than making boost. Nitrous, Propane Injection, computer tuners for newer engines, or mec
Adrianspeeder,
Don’t forget about the new generation of turbos, plus the twin turbo setups for Cummins diesels, they’re making more power with less fuel nowadays.
Fuel economy was one of the contributing factors to the demise of the GMC/Detroit 2-stroke diesels, even the Silver 92s couldn’t stop the tide.
Speaking of sparks, I’ve cleaned the carbon out of my share of EMD engines, The “Roman Candle” effect looks really nice at night.
Randy
Ooo good point Randy on the new turbos…
Variable Vane thingies seem to be the new deal. Sorry I don’t know much about them, but if it puts more horses to the wheels, I’m for it.
For cummins twin turbos, which engine do you mean, or do you mean aftermarket?
For the big '07 redesign of the Ford Superduty, the big rumor is the 6.0L powerstroke being bored out to 6.4L and going with a twin turbo deal. It will be something if it works…
Adrianspeeder
We had cylindrical spark arrestors on the Milw Road are the ones down under similer to those?
Still got to keep them clean right .
Randy
Anyone have pics?
Adrianspeeder