| Author | Message | ||
| Henry 96A3 (Hank)
Registered Member Username: Hank Post Number: 58 Registered: 11-2005 Posted From: 69.129.124.111 Rating: N/A |
So what's the deal with all these Detroit 2-71 powered generators you see on ebay all the time? They're watercooled, run at 1200 rpm and are always being sold pretty cheap. Are they loud as heck? Just plain too physically big? They sure look heavy duty. Hank | ||
| Ed Jewett (Kristinsgrandpa)
Registered Member Username: Kristinsgrandpa Post Number: 259 Registered: 2-2003 Posted From: 64.24.212.67 Rating: N/A |
Check the weight. I checked them out a long time ago and if I remember right they were in the 2000/2200 lb. range. About what 4 good diesel gensets would weigh. Also the 2 cyl. would be more prone to vibration than a multi-cyl engine. Ed. | ||
| Richard Bowyer (Drivingmisslazy)
Registered Member Username: Drivingmisslazy Post Number: 1664 Registered: 1-2001 Posted From: 75.108.82.163 Rating: N/A |
1200 rpm means a 6 pole alternator which is significantly larger and heavier than an 1800 rpm, four pole alternator. Also engine must be over sized to put out adequate hp at 1200 rpm as opposed to 1800 rpm. A 1200 rpm unit is ideal for continuous duty or for thousands and thousands of hours operation with little or no trouble. Not really ideal for an RV unit due to size and weight. Richard | ||
| David Hartley (Drdave)
Registered Member Username: Drdave Post Number: 674 Registered: 5-2005 Posted From: 67.78.176.54 Rating: N/A |
Not to mention that one of those will barely fit in the back of a pickup truck. I saw one that was over 4 feet tall with the radiator and base. They also suck fuel at an alarming rate compared to a kubota, isuzu or RV style diesel generator. Great for a last forever standby generator, heavy and really built to keep on running. | ||
| John Ferguson (Jarlaxle)
Registered Member Username: Jarlaxle Post Number: 10 Registered: 7-2006 Posted From: 63.235.27.90 Rating: N/A |
Isn't there a guy here running an 1800RPM 2-71 in an all-electric conversion? Seems it might be workable in that case...and heck, you already HAVE one DD, so at least the main & genset engines will use the same oil/filters.  | ||
| Henry 96A3 (Hank)
Registered Member Username: Hank Post Number: 59 Registered: 11-2005 Posted From: 69.129.192.108 Rating: N/A |
Ed, yer right. They weigh a ton+ (literally). Are buses designed to hold that much weight in one baggage bay? I guess some folks carry 200+ hundred gallons of water in one bay. The other issue would be the height of the thing. There's one listed on there that's 40" tall on rails. I like the heavy dutyness of it and the fact that you can get a super quality unit for under $3K but if it's a fuel hog, the savings wouldn't be very long term with today's fuel prices  I wonder if they leak oil like their big brothers in the back of the bus? Just think: two puddles of oil under your bus!!! Thanks for the info. Hank | ||
| JR Lynch (Njt5047)
Registered Member Username: Njt5047 Post Number: 40 Registered: 7-2006 Posted From: 69.132.238.127 Rating: N/A |
Those 2/71 gensets are generally railroad take outs. They hung on refers and supplied the power for refrigeration units. They are using truck style compact units now and removing the DDs from service. The DDs have had the bejabbers run out of them. They are not suitable at all for a bus genset. You would have to stand next to it to appreciate the size and the amount of noise that they make...sort of a "clank-clank-clank"...really noisy. And, as everyone has indicated so far...it's waay too big. Now if you wanted a standby for your home, and you're an electrical and DD genuis...then you may want one. There is a lot of info on the Yahoo Groups Detroit Diesel website. I'd avoid those things like the plague! I cannot be specific, but the genset head must be rewired to use for home powerplant they are either 120 or 240 (but not both?)and are being rewired to be useable...Richard may be able to expound on this, still...it ain't no bus genset. To get an idea of the size of the engine alone, take a look at a 6-71 bus engine...a 2-71 is the same height and width...just two cylinders of the six. Save yourself a lot of headaches and get a real diesel genset designed for an RV. JR (Message edited by njt5047 on August 27, 2006) | ||
| Richard Bowyer (Drivingmisslazy)
Registered Member Username: Drivingmisslazy Post Number: 1666 Registered: 1-2001 Posted From: 75.108.82.163 Rating: N/A |
Most commercial gensets can be re-wired for 120 or 240 volt output. However, be very careful. The output may be three phase instead of single phase. If so (three phase) then it is really of no use as and RV unit. Richard | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 1 Registered: 8-2006 Posted From: 207.231.80.150 Rating: N/A |
Everyone above is right! These were built for Pacific Fruit Express, a joint venture of Southern Pacific & Union Pacific railroads, in the mid 60s. They were not built with battery charging, as they were expected to be started and run continuously for about 2 weeks per load. They would keep a frozen load at minus 10 degrees for 3 weeks at 110 outside on a 400 gallon tank of fuel. They are 3 phase, with 120 volts to GROUND, no neutral wire, and not suitable for RV service. | ||
| Richard Bowyer (Drivingmisslazy)
Registered Member Username: Drivingmisslazy Post Number: 1667 Registered: 1-2001 Posted From: 75.108.82.163 Rating: N/A |
George, any possibility they were 400 hertz output also? That is a very common voltage for 400 hertz units. i.e. 120 volt, three phase delta. Richard (Message edited by drivingmisslazy on August 28, 2006) | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 2 Registered: 8-2006 Posted From: 207.231.80.150 Rating: N/A |
Richard, Sorry I wasn't clear, they are actually 208 Wye connected, phase to phase, with 120v from any leg to GROUND. They didn't put a charging alternator on them, and used an odd cranking battery so that they (the battery)was of no value in an automotive application. All mechanical original controls, pull a lever to start, pull another to stop. A 120 volt solenoid gave speed increase when the temperature was above the setpoint, and another 120 shut the engine down for low oil or high temp. The engine idled unless it was told to speed up, or stop. 12v start, we would have to jump 10 or 12 of them a day, after they were spotted empty in a packing shed. I have seen oil pans so full of sludge that they had grooves in them where the throws of the crank were. I think we had about 16,000 of them in 1970? About 2500 still left. The Santa Fe had a bunch with 3-71s, I don't know why. | ||
| Richard Bowyer (Drivingmisslazy)
Registered Member Username: Drivingmisslazy Post Number: 1668 Registered: 1-2001 Posted From: 75.108.82.163 Rating: N/A |
Thanks for the update George. I have run into thousands of different gensets over my career but I never saw one of these. Sounds like they would be great for an emergency standby unit at home, especially if they are 12 wire and could be connected for 120/240 volt single phase output. Richard (Message edited by drivingmisslazy on August 29, 2006) | ||
| George
Unregistered guest Posted From: 207.231.80.150 Rating: N/A |
These ALL were used by 3 or 4 railroads as the power for a mechanical refrigerator car. The equipment in the car was all electric, so in case of an engine failure, another empty car could be coupled to it, motor end to motor end,(they had a big 3-phase plug with about 10 feet of cord) and the trip completed without having to unload the car. They are 3 phase, with 120 volts to GROUND, no neutral wire, not really suited to motorhome service. They are the proverbial brick outhouse, strong and durable, but VERY heavy and noisy. They would keep a 50 foot refrigerator car at minus 10 degrees inside, at 100 degrees outside for 3 weeks on a four hundred gallon fuel tank. They were all built in the middle sixties, most were removed in the nineties when carload refrigerated business declined. Now, we are using a "Kubota-Isuzu" style, smaller "light" weight unit which drives the compressor directly, as in most refrigerated trucks. The three previous posts are all exactly correct! |