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Honda GX160 acting weird...

Discussion in 'Chainsaws and Power Equipment' started by Jon_E, Sep 11, 2018.

  1. Jon_E

    Jon_E

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    As the title says. It's on a Timberwolf TW-P1 splitter. From a cold start, I fire it up and set it to half-choke to warm up a touch. If it is moved to off too soon, it will stall. So I leave it at half for a while and then move the choke lever to off. FYI, clean fresh ethanol free gas, new spark plug, new air filter.

    It runs for 2-3 minutes, and then will stall under load, generally when starting a split or when the ram reaches the end of it's extension and I don't retract it fast enough. This is often, but not always, accompanied by a pop or two or even a full gunshot-loud backfire. If I let it sit for 2-3 minutes, it will start right back up, and we do it all over again. If I try to restart it immediately, it will not start. This is usually a one-pull or less machine once warmed up.

    However, if I leave the machine at around 2/3 choke, just below the point where it starts to splutter and gasp for air, then it will run just fine and will not stall no matter what I do to it, and will run that way until the tank is dry. The second I move the choke lever even a hair towards the off position, it starts exhibiting the stall/backfire symptoms again.

    The symptoms do not change even if the machine is tilted one way or the other.

    Any ideas on what to check first? I am not much of a small engine mechanic, so I may need some pretty detailed instructions. I am guessing that there is some crud in the carb, but tearing that apart makes me nervous.
     
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  2. JustWood

    JustWood Guest

    Had a similar problem on a GX390.
    Even though it has a new plug ,,, try another before you goto a lot of trouble. New plugs can be bad.
    My problem ended up being the plug even after I cleaned everything up
    If that doesn't work
    I'd clean the sediment bowl , gas tank and or try sea foam .
     
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  3. huskihl

    huskihl

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    I have 6 of them. After 5 or 6 years they need a good dose of seafoam. The main jet is partially plugged off or the needle won't open fully. A few ounces of seafoam added to 1/8 of a tank of fuel. Shake it up and let it run for 10 minutes to get into the carb. Let it set for a week or 2 and try it. Mine have all run great after a month of sitting with this treatment. Not sure if a week is long enough or not
     
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  4. brenndatomu

    brenndatomu

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    Yeah, try the plug first...but I'm betting there is something in the carb. Letting it soak with seafoam or some sort of fuel system cleaner in it is worth a shot too.
    Most of those Hondas can be checked without removing the carb, just remove the jet-holder bolt from the bottom of the bowl...the main jet will be in that "bolt" (IIRC) blow through it with the straw on a can of carb cleaner (protect your eyes! and your hands if you have sensitive skin) and then an air hose too, if you have one.
    Also make sure the sediment bowl (if it has one, and it probably does) is clean (10mm wrench to remove) And while the carb bowl is off, turn the fuel on, see if the fuel flows freely from the float needle/seat when the float is hanging.
    We bought a new water pump at work with a Honda and it acted the same way as yours from brand new...I backed the fuel adjustment screw out a little, which helped, but it didn't really run right until I ran a micro drill bit through the main jet, just big enough to bump the effective jet size up a size or two. Most people would just buy the next size bigger jet.
    If you go to adjust the fuel screw, it probably has a plastic "anti-tamper" thing on the screw that will have to be defeated...some can be cut, some can just be pulled off with a pliers, I don't recall now how ours was.
    If you google Honda carburetor cleaning or service, I bet there is a ton of vids on you-tube.
    Here's one...honda engine carburator cleaning video - Bing video
     
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  5. saewoody

    saewoody

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    Sounds like all these guys have you on the right track. Sounds like a carb issue to me.


    Sent from my iPhone using Tapatalk
     
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  6. Horkn

    Horkn

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    Yes, follow what brenndatomu outlines. It sounds exactly like a partially clogged jet. It sounds like Honda made it really easy to clean that jet out.
     
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  7. amateur cutter

    amateur cutter

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    ^^^^^^^^^^^^^^^^^^^^^^^^^
    This answer.
     
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  8. In the Pines

    In the Pines

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    look for a product called mechanic in a bottle It isn't magic but I think it works pretty well. I had a weed eater that sat for several years with fuel in it.
    I dumped the fuel poured this into it and it worked. It runs very well but I ended up having to replace the fuel lines.
    I always mix mmo into my fuel for my OPE. Or use seafoam instead, whatever you feel good using.
     
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  9. Canadian border VT

    Canadian border VT

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  10. 94BULLITT

    94BULLITT

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    After you do what brenndatomu said, add a stabilizer to the gas. Startron seems to be the favorite these days. Try to start it once every month or two, to "flush" the old gas out of the carb.
     
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  11. brenndatomu

    brenndatomu

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    This video is more in depth, and he is working on a GX160 specifically. Keep in mind that what you (probably) need to do can be done without completely removing and disassembling the carb as he does on this video. So if you watch both, use the details given in the second one to service the carb while on the engine as they did in the first vid.
    The second one does show how to get that fuel screw (pilot) anti tamper cap off...it doesn't need to go back on either.
     
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  12. Bret Hart

    Bret Hart

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    If it's less than maybe 8 or 10 years old there was a lot of gas cap trouble due to venting issues. Would make the engine act exactly like you describe.
     
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  13. RCBS

    RCBS

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    I saw quite a few units that had black plastic caps with venting issues...mostly from people setting it on the muffler to refill the fuel tank. :picard: Easy cap check is to loosen it just a bit and run the engine and see if the symptom disappears.

    Some very good advice given in this thread. I would like to add checking your valve clearance. Intake should be ~.006 Exhaust ~.008. Very simple to check. 1 10mm bolt on valve cover, remove. Set engine at top dead center (can pull the sparkplug and shine a light into the cylinder to see when piston is at the top of it's stroke). Check clearance with feeler gauge like this
    valves.jpg

    If the corresponding gauge will not slide in there, they are too tight. Conversely, if it slides between and moves around easily they are loose. Adjustment is made by loosening the 10mm top nut and tightening or loosening the 14mm(?) beneath the 10mm.

    I bring up the valves because I seldom if nary ran into a backfiring Honda engine that didn't need a valve adjustment. Symptoms also point to possible carburetor issue as stated above.
     
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  14. nsmaple

    nsmaple

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    I don't have a GX but do have a GC. It acts exactly the same at times, and is always dirt in the carb. It only takes a very tiny spec in the wrong spot. If it is bad or old fuel related, Seafoam might do it, but it won't dissolve solid specs like a piece of wood or grain of sand type thing. And sometimes it is a real PITA to find the problem spec since it can be tiny and hardly see-able - usually needing complete carb disassembly, sometimes more than once. I have been meaning to add an in-line filter to mine but still haven't got around to it - also highly recommended.
     
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  15. Bret Hart

    Bret Hart

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    Honda bulletin.
     

    Attached Files:

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  16. Tiewire

    Tiewire

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    A torch tip cleaner works well to clean holes in the main jet also.
     
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  17. Jon_E

    Jon_E

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    Alright thank you guys for the advice here, I'm going to try a couple things offered here over the weekend, see if it helps. I do have the old style metal gas cap so that may be part of the problem.
     
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  18. lknchoppers

    lknchoppers

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    Flush out the gas tank with fresh gas and clean out the carb bowl. I had the exact same problem on mine, it was basically a little water in the fuel system, I saw it in the container after I drained out the carb bowl. That carb is super easy to take off and the bowl is very easy to pull off. I also made sure all the jets were clear and the float valve was clean. One thing about the gas cap on the GX160 is if it ever gets rained on water will get into the gas tank. I would not mess with anything else except clean the air filter. Good Luck.
     
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  19. nsmaple

    nsmaple

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    ^ Good words. Also, when I do the flushing routine, I try to drain all the gas (tank & carb) into a glass bottle soI can check on how dirty or watery it is. Carb would be tricky - but sometimes it really helps to know what's in the tank. Woody bits seem to have found their way into my tank over the years, no idea how.
     
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