Choosing a good generator

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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Re: Choosing a good generator
    mtdoc wrote: »
    And - for an example of a generator NOT well matched to the load:

    If they all press "Send" at once the surge amps could be big. Real Big. Better safe than sorry when dealing with Texting Zombies with dead cell phones. :confused:
    --
    Chris
  • swmspam
    swmspam Solar Expert Posts: 57 ✭✭
    Re: Choosing a good generator

    Lessons learned from NYC and Sandy ...

    Ditch the Home Depot generators. Use a Honda or Yamaha inverter generator for fuel economy. Have fuel on hand. Your generator will be running long after your neighbors are standing in line at the gas station. Judging from the "firearms and fistfights" stories from the besieged gas stations, I would assume those things would eventually find you at home, attracted by the noise of your solitary generator still running after all the gas stations shut down. Either build a generator shed or equip your generator with additional noise absorption.

    Natural Gas, known as a "stable fuel supply", was shut off (Reuters Natural Gas Article). This is what likely caused telecommunications to fail. Without NG, the big generators at telecom stations didn't have any fuel, and there goes the internet, land lines, and cell phones. Have a multi-band radio receiver. Better yet, get your ham radio license, or at least have a CB.
    Vic wrote: »
    If you have Nat Gas, it is relatively inexpensive, and deemed to be a "very Reliable" fuel source.

    Ooops! Guess not!

    Even Bill O'Reilly commented on his cable TV show about disappointment with his "$10k generator" that failed after Sandy pummeled his neighborhood. He was railing on the vulnerability and instability of the grid system. This makes me think he had a Natural Gas standby installation that failed when the gas went down. Wonder if it was a Generac? The story is a good example. If you don't have extra fuel on your person, then you risk not getting any more.

    Anyone have experience with the Honda or Yamaha tri-fuel conversion kits? I've seen kits that "permanently" convert to vapor fuel, although some kits suggest you can switch between fuels easily. I'm thinking of a Honda inverter generator connected to natural gas in a small shed that I can wheel out and use with gasoline if needed.
  • mtdoc
    mtdoc Solar Expert Posts: 600 ✭✭
    Re: Choosing a good generator
    swmspam wrote: »
    Anyone have experience with the Honda or Yamaha tri-fuel conversion kits? I've seen kits that "permanently" convert to vapor fuel, although some kits suggest you can switch between fuels easily. I'm thinking of a Honda inverter generator connected to natural gas in a small shed that I can wheel out and use with gasoline if needed.

    One of my Honda eu2000i's has a triple fuel kit from Central Maine Diesel. I haven't tested it extensively but so far it seems to work just fine on propane or gasoline.
  • mtdoc
    mtdoc Solar Expert Posts: 600 ✭✭
    Re: Choosing a good generator

    I subscribe to a Yahoo Honda eu2000i mailing list. This email came in today - thought I'd share it since it is relevant to the recent generator discussions here:
    Our power is finally restored, near the NJ border about 20 miles NE of
    Philadelphia. The little EU2000 that my neighbors laughed at as they had
    their el-cheapo 4000-9000 watt generators, performed flawlessly. I took it
    out of the side box on my truck and just dropped the fuel line (from
    extended run tank) into a 5gl gas can, making sure it reached bottom, and
    protected it from water and debris ingress. I ran it for five minutes,
    shut down, and did an oil change knowing it may be running quite a while
    non-stop. So, 62 hours later, and still not having emptied the 5gl can, it
    was finally time to shut down. Meanwhile two people on my block had
    generator failures, both off brand Chinese units ... but ... they were
    cheap. The others were pouring five gallon cans of gas in every three to
    eight hours.

    What was I able to power with my 'meager' 2000?
    1. refrigerator/freezer in kitchen
    2. full size freezer in basement
    3. oil furnace for hot water, combined with pump for water circulation for
    baseboard heat.
    4. three or four lights, all CF or LED
    5. 42" flat screen TV and DVD player while cable (still) out
    6. 17" laptop computer
    7. 50Amp @ 13.8VDC power supply for amateur radio station operations,
    running two 100 watt radios on HF, VHF, and UHF.
    8. miscellaneous chargers to keep cell phone charged which provided
    continuous 4G connection to internet.

    All the above without any manual intervention for power management.

    By disconnecting #1, #2, and #3, I was able to run a 1200 watt microwave
    but that really had a high startup load. I went back to my truck and got
    the 700 watt microwave which was much more manageable and I could disconnect
    only 2 of the 3 listed items with no overload.

    The EU2000 used less than five gallons of fuel with a run time of 62 hours
    to provide a habitable environment for the duration of our power outage.
    More power would have allowed more amenities, but we were able to have more
    than a minimal level of comfort. Heat, hot water for showers, food
    protected from spoilage, and ability to cook, along with availability of
    entertainment to pass the time, as well as maintaining communications via
    amateur radio for weather reporting and updating status of our community.
    If I had felt more power was needed I would have brought out my 'emergency
    generator', the old Eu2000 with over 8,000 hours on it!

    Ray
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Choosing a good generator

    i can see a potential problem with the genny handling all of that if the startups are at the same time. that would be just too much in surge. it is still very nice to go that far with so little fuel, but the indicated loads would not have all been constant over that entire time period or he would've certainly used more fuel. i still would not mind having one of these over my gas guzzling 4kw generac. maybe one day.:D
  • Rngr275
    Rngr275 Solar Expert Posts: 127 ✭✭
    Re: Choosing a good generator

    So far so good with my EcoGen. I don't have a lot of hours on it yet so I am not willing to do a full endorsement. I was warned and it seems to be true... WHATCH THE OIL LEVEL! Seems like both my EcoGen and my Honda 2000i use much more oil than a motor of similar size (tractor, lawn mower, etc.) Not sure why but I have made it a point to check the oil at the end of every run session and I change the Honda oil quite regularly (take less than a qt).
  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Re: Choosing a good generator
    mtdoc wrote: »
    One of my Honda eu2000i's has a triple fuel kit from Central Maine Diesel. I haven't tested it extensively but so far it seems to work just fine on propane or gasoline.

    I would exercise some caution in using LPG in an engine designed for gasoline, especially operating at continuous high loading. Engines designed for LPG have stellite valves and hardened valve seat inserts. LPG has a slower flame speed (and lower thermal efficiency) than gasoline at a given compression ratio. So at high piston speeds it tends to still be burning when the exhaust valve opens, causing higher exhaust temp and accelerated wear to the exhaust valve face and seat. You really need to bump the compression ratio a couple points, or advance the ignition timing at a lower compression ratio, to burn LPG effectively. Bumping the ignition timing on a lower compression engine starts the burn earlier so the peak cylinder pressure reaches a minimum of 800 psi @ TDC.

    Thermal efficiency is a function of the compression ratio as well as the fuel. With a given set of parameters (compression ratio, valve timing events, spark timing, stroke length, mean piston speed), fuels with a lower energy density will always exhibit lower thermal efficiency. So the only advantage to using LPG in an engine designed for gasoline is use as an emergency fuel, and there are several disadvantages.
    --
    Chris
  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Re: Choosing a good generator
    Rngr275 wrote: »
    So far so good with my EcoGen. I don't have a lot of hours on it yet so I am not willing to do a full endorsement. I was warned and it seems to be true... WHATCH THE OIL LEVEL! Seems like both my EcoGen and my Honda 2000i use much more oil than a motor of similar size (tractor, lawn mower, etc.) Not sure why but I have made it a point to check the oil at the end of every run session and I change the Honda oil quite regularly (take less than a qt).

    The reason the Honda's use excessive oil is because they spend too much time idling, or at partial power output/engine speed and low cylinder pressures. So the oil don't get scraped off the bore by the rings.

    With the EcoGen, make sure you load it as close as possible to full rated load during the initial 200-300 hours. The higher cylinder pressures will force the piston rings out against the cylinder wall and "seat" them in so they properly scrape oil off the bore. If you run the EcoGen at partial loading during breakin it will glaze the cylinders and you'll have an oil burner for life. The EcoGen's v-twin is 9.2:1 compression ratio, so it operates at higher cylinder pressures than a EU2000 et al. But it still needs to be worked and don't baby it during breakin. We had about 1,100 hours on ours when we replaced it, and it had stopped using oil after the first ~200 hours, and would go the full 500 hours on an oil change and only use about a half pint.

    I don't know what a lot of folks use for oil, but I recommend Mobil 1 synthetic for air-cooled generator engines (I have absolutely no affiliation with the company that sells it). Experience has shown me that Mobil 1 will never carbon foul the top piston ring and underside of the valve heads, and it withstands the high temperatures that air-cooled engines run at better than conventional oil does. I use 5W-30 in mine at temps below freezing, and switch to 10W-30 in the summer time.
    --
    Chris
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Choosing a good generator
    ChrisOlson wrote: »
    I don't know what a lot of folks use for oil, but I recommend Mobil 1 synthetic for air-cooled generator engines (I have absolutely no affiliation with the company that sells it). Experience has shown me that Mobil 1 will never carbon foul the top piston ring and underside of the valve heads, and it withstands the high temperatures that air-cooled engines run at better than conventional oil does. I use 5W-30 in mine at temps below freezing, and switch to 10W-30 in the summer time.
    --
    Chris

    I have a Eu1000 annd other than the factory oil fill I have used OPTI 4 in it ever since, change it once a year at end of season and put between 50 - 100 hrs a year, a lot of low (idle) time and interspersed with full out when the wife decides that the cabin needs a vacuuming, rest of time it powers chargers of varying power.

    Can't say that it has used any oil between changes that I have noticed. I am a fan of the OPTI products, started with Opti 2 in the outboard and went from there. the '2' version also has a gas stabilizer in it for over the winter storage.
     
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Choosing a good generator

    EU1000i with 6,000+ hours on it.
    Changed oil every 50 hours (really complete draining). Use cheapest 10W-30 oil I could get.
    It uses oil now, but very little. Most of its life it never swallowed a drop.
    Also, it rarely was run at maximum load.
    Takes more than 3 pulls to start it now; it's worn.

    EU2000i is being treated the same way. Has over 4,000 hours on it now and still doesn't use any oil.
    Again, cheapest oil I can get changed every 50 hours and it too rarely runs at maximum load.
    But this one has developed a frayed pull cord! I had to re-tie the know on it.
    Cold start (after sitting for days without use) requires two pulls. Next-day starts on first pull.

    And no I don't bother with fuel stabilizer as the gasoline doesn't sit for long.
    Fill up before Winter storage, turn fuel valve to 'OFF'; it's fine in the Spring (this is not a wet climate here).
  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Re: Choosing a good generator

    There are some fundamental differences in air-cooled vs liquid-cooled engines. The pistons expand at different rates across their diameter - it will expand more across the skirt than across the wrist pin as it heats up. So for this reason liquid-cooled engines use cam ground (typically cast) pistons, and because they can provide relatively precise control of operating temperatures, they run much closer tolerances.

    Air-cooled engines do not use cam ground pistons, and instead used forged pistons that are much stronger than what most liquid-cooled engines have. And they run much wider tolerances because they are expected to be able to operate under a wider range of temperatures.

    The advantages of air-cooled engines are that they will survive under conditions (dirt, dust and temperature extremes) that would kill liquid-cooled engines in short order. They are lighter than a comparable liquid-cooled engine. They are able to start cold and go to full rated load and speed within seconds without hurting the engine.

    Because of the differences, air-cooled engines also have different lubrication requirements than liquid-cooled engines. Some of the best lubricants for air-cooled engines were developed for the aviation industry. The first use of synthetics in aviation was during WWII in the Rolls-Royce Merlin V-1650, which was liquid cooled. It took a long time to get synthetics to market in the US but the aviation industry adopted it long before the automotive industry did because of the extremes that aircraft piston engines operate under.

    Air-cooled engines require low ash oil, and using regular automotive conventional lubricants in them will shorten their service life by 50% or more. Conventional lubricants rated for use in diesel engines (API CL-4 or CJ-4) are low ash and make excellent oils for air-cooled engines also. The top piston ring in a gasoline engine exposes the oil to temperature of around 350 degrees F. The top piston ring in a diesel exposes the oil to temperatures exceeding 1,000 degrees F and therefore the oils formulated for diesels make as good of lubricants for air-cooled engines as the synthetics do, at about the same cost.
    --
    Chris
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: Choosing a good generator

    Coot,

    RE an EU3000is genset, IMHO, it is the nicest one in the Honda line of Inverter gensets. Has the relatively largest fuel tank -- about 3.4 gallons if memory serves, is the quitest, electric start, and so on. The 3000Handi is a different breed, it is nearly half the weight of the larger electric start model, and able to be unloaded from a PU by many folks. For me the larger one is not a one person lift, tho at about 145 lbs or so.

    RE NG being "very reliable" fuel source, YES, in these very large events, seems that nothing is very reliable. Guess redundancy of resources in different locations might help. Also, neighborhood preparedness can help. If one neighbor is wiped out, others can help without a huge impact on the generous neighbor, and so on.

    The only large gaseous-fueled genset here is a Kohler Dual-Fuel model -- NG/LP, which had never seen before. NG was priority fuel, but if that fuel pressure is below the setpoint, the genset switches to LP. An not a fan of LP for gensets, but this one fits into the mix OK.

    I ran a Honda EU1000is for about 50 hours of power outage, in town. It ran the refer, TV, radio, Hammie radio, lights etc on almost no fuel. Was very happy to have it. The only real indication that we had power were a few lights. That genset is ssooooo unobtrusive that it could not be heard from any neighbor's residence. This is my favorite gen, and has the most hours on it, as it is so protable for even small jobs, like soldering in the field etc.

    These disasters are healthy wake-up calls, even for those of us who are somewhat prepared.

    Best wishes to all those affected by Sandy and the aftermath. Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Re: Choosing a good generator
    EU1000i with 6,000+ hours on it.
    Changed oil every 50 hours (really complete draining). Use cheapest 10W-30 oil I could get.

    coot, at least use a cheap synthetic in that poor Honda because the synthetic has all same-size molecules and will maintain a film that keeps the big end of that little aluminum rod off the crankpin under loading in a non-pressurized lube system.

    The auto industry has kept reformulating the oils used so they're pumpable thru really tight places, and removing the big particles (zinc and phos) that used to be in oil that provided "plating" on metal surfaces to keep them apart. Some engineer figured out that they can waste less hp turning oil pumps with this watered down stuff they're using and still keep bearings cool by constantly flushing them with it. But unfortunately, your little Honda GX200 ain't built that way. And that's why all the big oil manufacturers have gone to specific recommendations (or even special oils) for small air-cooled engines since the automotive 2011 model year. The motorcycle industry even raised the red flag on this latest SM classification because it don't stand up in bike engines.
    --
    Chris
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Choosing a good generator

    Chris;

    You know what just crossed my mind? Maybe my buying the cheap stuff avoids that ruinous "fine engineering" they put in to the "good stuff"! :p

    Back when detergent oils first appeared many auto experts were against them based on the idea they would keep the contaminants floating around in the lubrication system instead of settling 'harmlessly' out of the way in the bottom of the crankcase. I think there's some truth to that as I remember scraping sludge out of oil pans on oil engines, but not so much so on newer (post detergent oil use) ones.

    Of course I also used to put 90 weight gear old in my IH BC 190 because the engine was so badly worn. :roll:
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Choosing a good generator

    speaking of generators of the inverter type i saw a cheap one with 900w output and i believe it said .66 gallon capacity for about $240 under the brand name of duracell.
    http://www.sears.com/shc/s/search_10153_12605?keyword=duracell%20generator
    i showed that page will all of them to indicate there is a higher priced inv/gen model too. it seems odd to have that low of a price, but duracell is a known brand name for other things. do you think they are trying to nudge into the market by under pricing them? not to sure if they are any good, but they are staking their reputation by putting their name to them.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Choosing a good generator

    You mean the DS10R1i? It has a 2-stroke engine for one thing. That saves a few $ in production. Probably not as quiet as the 4-strokes.
    Curiously under "Fuel Type" it says "diesel". Everywhere else it says "gas powered". It also says "Engine RPM: 1000 Watts" and "Horsepower: 1200 Watts". Hard to know what it is with that kind of accuracy on the page! Maybe my browser isn't displaying the info properly?
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Choosing a good generator

    if i remember rightly it needs a dab of oil in the gas like lawnmowers do. 1 part oil to 30 parts gasoline. that technically would make it diesel i guess. what ratios does diesel fuel have?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Choosing a good generator
    niel wrote: »
    if i remember rightly it needs a dab of oil in the gas like lawnmowers do. 1 part oil to 30 parts gasoline. that technically would make it diesel i guess. what ratios does diesel fuel have?

    Well there used to be 2-stroke diesel engines way back when. GM made some with superchargers to scavenge the crankcase. I've no idea what sort of thing is available along this line now. As I recall the advantage was that the diesel had so much lubricating quality to it that oil wasn't added. But that was 50 years ago so I may be remembering wrongly.

    I've got 2-stroke gas engines here that run 16:1, 32:1, and 50:1. The highest ratio is the newest. 2-stroke SAABs and DKW's were 40:1 as I recall. You can fudge 'em a bit, but not too much. Over-oiled and they either fog badly or don't run. Under-oiled they blow up. Had a boat motor do that once; exploded the crankcase. Guy I got it from told me the wrong mixture for it.
  • mtdoc
    mtdoc Solar Expert Posts: 600 ✭✭
    Re: Choosing a good generator
    niel wrote: »
    speaking of generators of the inverter type i saw a cheap one with 900w output and i believe it said .66 gallon capacity for about $240 under the brand name of duracell.
    http://www.sears.com/shc/s/search_10153_12605?keyword=duracell%20generator
    i showed that page will all of them to indicate there is a higher priced inv/gen model too. it seems odd to have that low of a price, but duracell is a known brand name for other things. do you think they are trying to nudge into the market by under pricing them? not to sure if they are any good, but they are staking their reputation by putting their name to them.

    Interesting find niel. That is cheap for an inverter gen! I looked it up on Amazon HERE Reviews are "mixed":roll:

    I think if someone wants an inverter generator and absolutely cannot afford a Honda or Yamaha, the Chinese made Champion 2000watt models are worth looking at. When they first showed up at $500-600 at Costco and Sams club I think there were a lot of skeptics (me included). But they've been put through their paces by many people now and seem to be worth the price. You can find several YouTube videos of them being tested and compared to Hondas. You can also go the RV.net forum and read lots of peoples experience with them HERE on this thread - all 258 pages of it!
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Choosing a good generator

    i admit i'm a bit green on some of the newer terms for generators now, but what is carb compliant?
  • Rybren
    Rybren Solar Expert Posts: 351 ✭✭
    Re: Choosing a good generator

    Around here, Wal-Mart carries the Hyundai 2000si (2200W peak) Inverter Gen for less than $700 and Lowes cariies a Briggs and Straton for a bit more. The reviews I've seen for the Hyundai have been good, but I don't know anyone who has actually used one.

    added to your post that a walmart near me listed the hyundai hy2200si at $599.99. i did not see the 2000si. the 2200 sounds good. niel
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Choosing a good generator

    California Air Resources Compliant,,,CARB. A high degree of environmental standard, not just exhaust, but also vapor emissions.

    Tony
  • BB.
    BB. Super Moderators, Administrators Posts: 33,433 admin
    Re: Choosing a good generator

    The "HoneyWell" version (at Costco and other places) inverter/generator did not work out well--Ran OK, but became near impossible to start over time.

    I think the first generation was eventually mechanically replaced for folks that sent them in for warranty service (as I recall).

    Generac IX2000 review - its junk - with video

    Re: XW inverter charger behavior @120V (read Maverick's posts about Honeywell)


    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Re: Choosing a good generator
    You know what just crossed my mind? Maybe my buying the cheap stuff avoids that ruinous "fine engineering" they put in to the "good stuff"! :p

    That's totally possible. Maybe you're getting some of the good old SG stuff for cheap. I wish I could find some. But the only place that has it is the Honda dealer - HP4S - it's all they sell for motorcycles and Honda Power Equipment. They wanted 14 bucks for one quart. I told them I didn't want to pay that, but asked if I could at least a touch a bottle to see what really expensive oil feels like.
    --
    Chris
  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    Re: Choosing a good generator

    I had asked about caeb compliant in a different post but no one replyed. I didn,t want to take over someone elses post. I ask if the number of hours that a generator is carb compliant rated for reflects how long the runnibg life of the generator would be. If you get on this website it explains a little about how long some generators are carb compliant. http://www.yamaha-motor.com/outdoor/products/modelvideo/443/1187/0/video.aspx http://www.yamaha-propane-natural-gas-generators.com/ef2800i.htm This is the one I am interested in. You get what you pay for! :Dsolarvic:D
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Choosing a good generator
    solarvic wrote: »
    I had asked about carb compliant in a different post but no one replyed. I didn,t want to take over someone elses post. I ask if the number of hours that a generator is carb compliant rated for reflects how long the runnibg life of the generator would be. If you get on this website it explains a little about how long some generators are carb compliant. http://www.yamaha-motor.com/outdoor/products/modelvideo/443/1187/0/video.aspx http://www.yamaha-propane-natural-gas-generators.com/ef2800i.htm This is the one I am interested in. You get what you pay for! :Dsolarvic:D

    If I understand it correctly, the intent is that the gas powered device meet the CARB requirements for its entire lifetime.
    The manufacturer has to assure CARB that the unit will meet those requirements for the duration of the manufacturer's choice under standardized testing. And also cover any noncompliance during that period as a Warranty issue.
    In theory once the number of hours in that period have elapsed, it becomes the responsibility of the user to do any necessary maintenance to bring the unit back into compliance or else stop using it. I doubt very much that enforcement action is ever taken against the user though.

    Just as with motor vehicle emission standards, there are ways in which the engine can fail to meet the standards without any noticeable difference in performance (and therefore usefulness), but for motor vehicles the compliance is actually tested periodically as a licensing requirement. As such, it does limit the useful life of the vehicle.
    SMA SB 3000, old BP panels.
  • mtdoc
    mtdoc Solar Expert Posts: 600 ✭✭
    Re: Choosing a good generator
    ChrisOlson wrote: »
    I would exercise some caution in using LPG in an engine designed for gasoline, especially operating at continuous high loading. Engines designed for LPG have stellite valves and hardened valve seat inserts. LPG has a slower flame speed (and lower thermal efficiency) than gasoline at a given compression ratio. So at high piston speeds it tends to still be burning when the exhaust valve opens, causing higher exhaust temp and accelerated wear to the exhaust valve face and seat. You really need to bump the compression ratio a couple points, or advance the ignition timing at a lower compression ratio, to burn LPG effectively. Bumping the ignition timing on a lower compression engine starts the burn earlier so the peak cylinder pressure reaches a minimum of 800 psi @ TDC.

    Thermal efficiency is a function of the compression ratio as well as the fuel. With a given set of parameters (compression ratio, valve timing events, spark timing, stroke length, mean piston speed), fuels with a lower energy density will always exhibit lower thermal efficiency. So the only advantage to using LPG in an engine designed for gasoline is use as an emergency fuel, and there are several disadvantages.
    --
    Chris

    Thanks Chris. Great info! I'd realized that there were some drawbacks of running on propane, lower power output for one, but did not understand the mechanics and had not considered the longer term implications. I appreciate the education. In my case propane use with my tri-fuel Honda eu2000 would just be for emergency use -in case gasoline becomes hard to purchase. Would be nice to be able to easily advance the spark timing when running on propane but I suspect it is not. The nice thing about propane is the ability to do long term storage of large amounts. We use propane for cooking and have a large tank - always plenty on hand.

    There are some inexpensive portable propane only generators out there - Generac makes one - but I assume they are basically junk and would not hold up to long term use any better than a Honda engine running on propane.
  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Re: Choosing a good generator
    mtdoc wrote: »
    In my case propane use with my tri-fuel Honda eu2000 would just be for emergency use -in case gasoline becomes hard to purchase.

    That's a really good reason for having a dual fuel generator. In the aftermath of Sandy it's impossible to buy gasoline in most places there. If you have a 500 gallon tank of propane sitting in your back yard, being able to tap into it to run your generator would be a godsend.

    You're better off with your Honda with a conversion on it than the little Generac LP3250, IMHO. It's only a 500 hour generator in the first place, and all it is is a GP3250 with the same plastic camshaft Chinese engine on it and a LP conversion done to it. I don't like to bash any companies, but when it comes to the Generac GP-series portables they are what they are - really, really cheap. They are pretty impressive for power output and fuel consumption. They just don't last.
    --
    Chris
  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    Re: Choosing a good generator

    In my case I have a gas well and think a tri fuel setup is the way to go for me. If the gaswell goes out of production I still have the propane or gasoline option. If the gaswell dies I would have to go back to propane anyway. Some of the gas wells around here are over 30 years old and still output gas. Since I am about 68 and my well is about 7 years old I hope ot last me for the rest of my lifetime. I think a honda or Yamaha could work for me but think I want Yamaha as the approve the trifuel setup and still honor the warranty. Solarvic
  • swmspam
    swmspam Solar Expert Posts: 57 ✭✭
    Re: Choosing a good generator

    Since we're on an oil discussion, here are my $0.02.

    I caught on to Castrol Edge with Titanium SAE 10W-30 when trying to revive some lawn equipment. I also added a bit of Slick 50. Both the lawnmower and trimmer responded very positively. I'm sure they will work another few more seasons. They were headed to the garbage dumpster until Castrol came to the rescue. Now they're working better than they have for years! I'm not sure how much the Slick 50 contributed, but the Castrol Edge definitely was a game-changer.

    When I bought my Yamaha EF2000iS, I used the Castrol Edge for the first fill and ran the generator hard for an hour. I also purchased the magnetic dipstick. After an hour, I swabbed the dipstick with a chem-wipe and analyzed the result with a materials analysis microscope. There were LOTS of visible and microscopic metal fragments present. I changed the oil. Attached is a photo of a swab after about 10 hours of (lifetime) run time. This generator sheds a lot of break-in material. I assume other engines are similar. God bless oil filters. I wish the Honda and Yamaha generators had oil filters.

    Lessons learned: Run generators hard and change oil often during first hours of life! The oil accumulates lots of break-in material that is otherwise circulated and causes wear and tear. Make sure you have a magnetic capture, either built-in or add one yourself. Use good oil. For me, that's the Castrol Edge in the gold-colored bottles. It's amazing stuff that's saved me hundreds of dollars by rejuvenating lawn equipment that would otherwise be in the trash dumpster.