Generator advice

MarkC
MarkC Solar Expert Posts: 212 ✭✭✭
Know this is somewhat off topic, but relevant (at least to me!):

I am selling my emergency backup 6500 Amico gen set for a propane based system - tired of "babying" the gasoline based system.
The latest problems revolve around backfiring through the carburetor after running for 1 or 2 minutes and then eventually stalling.  I've done most recommended "solutions" (carb cleanout, float test, fuel needle valve/seat cleanout, check fuel petcock, tank and cap, etc).  

After much searching, I realised that my favorite "solar" site likely has more knowledge base that any other - although I certainly recognize it's not the main focus.  If anyone can refer me to a truly knowledgeable forum and/or can add to the knowledge base of this site, I'd be grateful.




3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  

Comments

  • wellbuilt
    wellbuilt Solar Expert Posts: 763 ✭✭✭✭
    How about a simple valve adjustment ,  I dident look to see what type of unit it is but a valve adjustment seem to help  with your symptoms  . 
     Valves opening early could cause back fire and stall . 
     Chattering . 
     I just did a valve adjustment on 3 genarator and they are running like new again .
     Granted the valves would have to be way out of wack to back fire 
    Know this is somewhat off topic, but relevant (at least to me!):

    I am selling my emergency backup 6500 Amico gen set for a propane based system - tired of "babying" the gasoline based system.
    The latest problems revolve around backfiring through the carburetor after running for 1 or 2 minutes and then eventually stalling.  I've done most recommended "solutions" (carb cleanout, float test, fuel needle valve/seat cleanout, check fuel petcock, tank and cap, etc).  

    After much searching, I realised that my favorite "solar" site likely has more knowledge base that any other - although I certainly recognize it's not the main focus.  If anyone can refer me to a truly knowledgeable forum and/or can add to the knowledge base of this site, I'd be grateful.





    Out back  flex power one  with out back 3648 inverter fm80 charge controler  flex net  mate 16 gc215 battery’s 4425 Watts solar .
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Have you considered diesel as a fuel, propane has issues as usually they are converted gasoline units, but then again I'm a fan of diesel, especially mechanical, without electronic control, simplicity has a quality of its own.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • wellbuilt
    wellbuilt Solar Expert Posts: 763 ✭✭✭✭
    I think the 1 or 2 Minutes of run time is an indicator , the unit get hot and everything expands and valves go out of wack .  I don’t know any one that adjusts valves until there is a problem 
    Out back  flex power one  with out back 3648 inverter fm80 charge controler  flex net  mate 16 gc215 battery’s 4425 Watts solar .
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    I'm also a fan of diesel, but for a rarely used emergency backup I'd also be considering propane. Diesel probably has fewer fuel storage and stability issues than gasoline, but does still have issues. My understanding is propane is better in this regard, so may be more suitable for this application.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • MarkC
    MarkC Solar Expert Posts: 212 ✭✭✭
    I'm set on propane as I have an electric heater in the cabin, and is not useable when on emergency/solar/gen power.  I want to be able to add a propane heater in the cabin in the future also (not used much in South TX).  The unit probably has only 10 hours total run time and from my experience with auto and motorcycle engines, valve lash issues usually happens slowly and over hours and hours of operation.   And in some cases, it starts backfiring within 10-20 seconds.   My gut tells me I still have a carb problem - but don't really know what to look for.
    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    A new replacement carb runs about $38... have you considered that? pretty inexpensive...
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    Does it keep backfiring after it warms up a bit?

    How old is the gas?

    Is there gas in the exhaust?
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • MarkC
    MarkC Solar Expert Posts: 212 ✭✭✭
    westbranch - I'm almost to the point of buying that carb on ebay - it's so cheap!  I'm up for one more shot at the carb however as it is a 5 minute job to remove it.

    Estragon;
    The unit seems to run fine from anywhere from 10-20 seconds to a couple of minutes - not enough time for heat to have much effect on the engine itself??  It regulates the rpm fine during that time.  After that variable time span, it will start popping and the rpms will slow and begin to vary.  Usually within a few seconds, it will pop loud and eventually stop (but not like the ignition is cut).  I have been able to hold the throttle in a constant position to keep it running a few seconds longer, but eventually it will lose rpms, pop the cover off and stop.
    The gas is new (actually two new flushes of the tank). Don't think there is any gas in the oil or in the exhaust - no backfiring/flames from the exhaust ever.  Just blows the cover off the intake filter!  Lot's of gasoline vapor left in the intake after shut down.  I wonder if the float level is messed up somehow - or the fuel needle valve is still leaking thru?  Just guessing.

    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • MarkC
    MarkC Solar Expert Posts: 212 ✭✭✭
    Disassembled carb one more time - removed all parts, all look like new with no signs of varnish or blockages in passages/metering holes.  Unit starts fine and runs for 10 seconds or so, then starts cycling, gets worse and finally starts popping and shuts down.  Was able to keep it running for an extended time (minute?) by partially throttling the choke, however eventually the cycling starts and shuts down.  Pulled valve cover and plenty of play in the valve rockers.  Guessing some problem with float/valve, but there is no adjustments and all looks so good.
    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Could be plug gap or other ignition issue (to wide of plug gap, worn/rounded plug electrode, etc.).

    One product that works pretty good for varnish removal is "Sea Foam" gasoline treatment. Many people swear by it... I used it on my lawn mower after it varnished up over winter (basically would only run if 1/2 choked).

    https://seafoamsales.com/sea-foam-motor-treatment/

    Pour some in the tank, start/run a bit. Turn off and let it set for a few hours, try running again.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • wellbuilt
    wellbuilt Solar Expert Posts: 763 ✭✭✭✭
    Turn the fuel off and try to get the unit to run on starting  fluid  If it runs  on starting fluid and you can keep it running ,you  definitely  have a carb problem . 
    Out back  flex power one  with out back 3648 inverter fm80 charge controler  flex net  mate 16 gc215 battery’s 4425 Watts solar .
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    edited July 2018 #13
    Two things to try, replace the spark plug with a new one, check the emulsion tube found under the main jet, the small holes are prone to getting plugged which causes an over rich mixture. Disregard if these have been tried.
    https://www.google.com/search?ie=UTF-8&client=tablet-android-samsung&source=android-browser&q=carburetor+emulsion+tubes#imgrc=199ZgS1AZTTHKM:
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Another quick carb trick... With the motor running, place you hand over the carb intake--This causes a high vacuum and reverse fuel flow in some of the passages--Many times this will clear out blockages.

    Be careful doing this... If there is backfiring, could spray fuel+fire onto your hand/sleeves/arm (use a board, leather, something else to block air flow?).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • MarkC
    MarkC Solar Expert Posts: 212 ✭✭✭
    BB - tried the "vacuum" trick with no change. 

    Tore it down again and soaked in alcohol, cleaned all passages with a small wire and blew everything out.  This time it would run for extended time on 3/4+ open choke.  When I tried opening full, it stalled immediately and as I choked it to keep it running, it backfired and blew off the choke valve gate off **.  Ordering a new carb ($23).  I'd guess either the float is too low in the bowl, and/or there is still a passage plugged.  Done with this carb.  I'll post when the new is installed.  It shows an idle air bleed screw that is adjustable, which might help resolve the idle/no load surging?  I won't be closing the choke again :#

    **I wear safety glasses and gloves.  Luckily the choke valve gate missed me and went about 25 feet.  Don't know where the screws/post are.   Could have seriously damaged an eye.




    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    edited July 2018 #16
    Well, if it sucked the choke plate in, that would have fixed things up good !  Glad you are OK.

    Just had a buddy try some fancy shooting and he wrapped his hand around the cylinder of a revolver.  Took about 30 stitches to splice his finger back together, and it will never be quite the same.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • MarkC
    MarkC Solar Expert Posts: 212 ✭✭✭
    I don't have the best relationship with carburetors.   The carb on my KTM 300 stuck open on a jump several years ago - several broken ribs and collarbone later......

    I do wish I could have gotten to the actual problem to help future diagnoses - never figured out the KTM carb either - replace and move on.
    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • cow_rancher
    cow_rancher Solar Expert Posts: 117 ✭✭✭✭
    MarkC said:
    This time it would run for extended time on 3/4+ open choke.  When I tried opening full, it stalled immediately and as I choked it to keep it running, it backfired and blew off the choke valve gate off **.  
    If you have to choke it to run... then it's not getting enough gas thru the main jet, I have found that the pickup in the bowl is the main culprit for this, and on B&S engines it is in the nut that holds the bowl onto the carb, easily missed if you clean the carb.  My first solution to an engine that doesn't run quite right is.... replace the carb, much cheaper than taking it into a small engine repair that always wants to replace the plug and the air cleaner at the same time, I never get it back for less than $100.

    Rancher 
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    There is spray chemical called "carburettor cleaner" (also available as a liquid in cans for soaking parts).

    https://gumout.com/maintenance-aerosols/carburetor-choke-cleaner/

    The stuff is very aggressive and pretty much needed to clean varnish from old fuel out of carburettors and fuel passages. Avoid getting on your hands... It cleans the "oils" right out of your skin.

    In your case, if you can buy a new carb for a reasonable price--Probably about time.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • m151
    m151 Registered Users Posts: 39 ✭✭
    If the float needle seat is a plastic/rubber material it can swell shut. had this problem on a B&S engine. bought a new seat and it lasted for another few years. bought a Chinese replacement for $15 and it has a brass seat.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Some times the brain is a bit slow (mine) remembering..... 
    I had a similar problem with a 6 Hp Evinrude.outboard..  They used a rubber gasket between the metal throttle body of the carb and the PLASTIC top and bottom  pieces.  The issue is I (over) tightened the screws when re-assembling the carb after doing a good cleaning

    This reduced the clearance between the gasket and metal parts by mere thousands of an inch and the motor would run for a few minutes and them die as the rubber gasket would soften a tad and then block some or all of the  TINY idle orifices in the metal carb body..

    Don't know if there is something similar in your carb but it sure had me stumped for 2 years and made me a whiz at removing and disassembling that carb !  It was a local outboard engine mechanic that found it and told me there were torque specs for it... duhh...

     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Ethanol in fuels can cause many problems with small engines, corrosion of carburetors, hardening of plastics, degredation of seals and absorbtion of water, to mention a few. The fuel lines of my brush cutter need replacement every year, they turn to stone, cracking causing leaks, plastic floats are also known to fail causing incorrect levels resulting running problems. The Honda water pump on the other hand has an E91 compliance sticker, which allows the use of gassahol as its known here, never had any issues with it. Hopefully the new carburetor will sort things out, good luck. 

    https://www.theglobeandmail.com/globe-drive/culture/commentary/the-problem-with-ethanol-in-gasoline/article29103634/
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • aksala
    aksala Registered Users Posts: 57 ✭✭
     I hope the eBay carb fixes it. I just dropped my 12kw B&S V-Twin gas genny off at my local small engine shop. It suddenly refused to run more than a few minutes. Not the oil sensor, not the fuel pump, not the fuel filter, not the fuel strainer and not old fuel. I didn't have the patience to tear into the carb a second time. I have too many other projects already on the stack to add one more, so off to the shop it went. 
  • DanS26
    DanS26 Solar Expert Posts: 264 ✭✭✭
    Ethanol in gasoline is the death of small engines.  Open the carb up.....you will see white deposits everywhere....like grains of sand....will clog everything....some grains so small to clog every jet.

    I live in corn country.......no farmer I know will buy or store ethanol laced gasoline.  They will not use it in any of their small engines.  Very ironic since the price of corn is supported by the ethanol subsidy.

    Live by the sword ....die by the sword.
    23.16kW Kyocera panels; 2 Fronius 7.5kW inverters; Nyle hot water; Steffes ETS; Great Lakes RO; Generac 10kW w/ATS, TED Pro System monitoring
  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    Could be the ignition cutting in/out with heat (had this happen to me twice).  Or possibly a leak allowing air into the intake manifold (causing missing from being too lean).

    I am available for custom hardware/firmware development

  • arby
    arby Solar Expert Posts: 107 ✭✭
    backfiring through the intake side is usually a sign of a vacuum leak. Having to partially choke it is another sign of a vacuum leak. I would guess the leak is after the carb.
    3310 watts panels, Classic 200 controller, 8 Surette S530's, Xantrex 5548 inverter, Honda EX5500 backup Genny.
  • MarkC
    MarkC Solar Expert Posts: 212 ✭✭✭
    Installed the new carb, however the results were similar with backfiring and shutdown after a few minutes of operation (and blew off the choke plate again - easy repair).  However, several changes made the difference:
    -  Closed the air screw and backed off 1-1/2 turns (the new carb has an adjustment screw that was basically wide open when shipped).
    -  Replaced the spark plug - found that the insulator tip that surrounds the inside electrode was broken and loose!
    -  More gasoline - was low, but not out.

    Now seems to run fine and handles load well.
    Lesson learned - check everything!!
    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    edited August 2018 #28
    @MarkC said,  Replaced the spark plug - found that the insulator tip that surrounds the inside electrode was broken and loose!
    Rewind to post#13, probably was the spark plug all along, can't count how many times I've replaced an inferior one with an NGK and solved a running issue. 
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • MarkC
    MarkC Solar Expert Posts: 212 ✭✭✭
    Recent problem with new carb.  Appears gasoline leaked into the low oil pressure shutoff solenoid at the base of the carb and froze shut - don't know why it even shut?  Would not start due to no gas.  drained the coil out, re-installed and working fine again.  A new meaning to "check everything".  
    3850 watts - 14 - 275SW SolarWorld Panels, 4000 TL-US SMA Sunny Boy Grid tied inverter.  2760 Watts - 8 - 345XL Solar World Panels, 3000 TL-US SMA Sunny Boy GT inverter.   3000 watts SMA/SPS power.  PV "switchable" to MidNite Classic 250ks based charging of Golf cart + spare battery array of 8 - 155 AH 12V Trojans with an  APC SMT3000 - 48 volt DC=>120 Volt AC inverter for emergency off-grid.   Also, "PriUPS" backup generator with APC SURT6000/SURT003  => 192 volt DC/240 volt split phase AC inverter.  
  • t00ls
    t00ls Solar Expert Posts: 245 ✭✭✭

    I was getting ready to do a post about generator engine troubleshooting
    look for it