Honda GX340

admin

I've read a few posts about small engines and Honda in particular. I have a GX340 11hp that runs my 4000psi pressure washer. I think it froze up. One day I couldn't pull start it. I didn't know if it was the pump or the engine so I pulled really really hard on it and it finally turned.I pulled the pump and it spins fine. The engine will only start if I hit it with some starter fluid. When it starts I can't rev it up at all. It just dies. So I'm thinking I it needs to be rebuilt.I've rebuilt the top end on a honda atv engine before. I'm wondering if it's worth tearing into on this engine. Itslike 700.00 for a new one. Anyone ever rebuilt one?
Reply:I've rebuilt a few and my friend down the road runs a successful small engine business - he's done quite a few. They are simple to take apart, rebuild and get parts. What is the history on the unit - was it left outside, no oil, ran hard put away wet, ran without water (the pump/sprayer portion), does it have fresh gas, how long was it sitting?John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Looking for a Honda GX200 right now. By the prices and the HUGE Honda small engine following on the racing go kart forums, I would say it would be very well worth rebuilding. Heck you can even hop it up!These guys are getting 20hp out of a hopped up 5.5Hp Honda!!!!! If nothing else, I bet you could sell it the way it is and use the money (plus some out of pocket money, of course) towards buying a brand new one. That way skipping the rebuild process and down time.Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:try somthing easy first! replace the spark plug, take off the float bowl and spray some carb cleaner into the jet, drain and replace the gas. and change the oil just incase it was siezedhard starting=bad plug, or dirty carb usually. make sure the choke is closing all the way to.honda carbs are cake to work on! usually all it takes is spraying carb cleaner up into the jet, a stream for a few seconds should do it (the jet is right behind the bolt that holds the floatbowl on and youll hear it spraying through the carb into the intake).if thats not it, it may be worth it to replace the carb (check the price on a new one, some honda carbs are less then $30 (some are alot more so check the price)) once you get it so it starts without carb cleaner, if it still wont rev, let it idle for an hour then try it. it may be because it was siezed. it will eventually work its way to run right or itll continue to deteriorate. remember these engines have no bearings. the crank rides against the block. the rod rides against the crank. theres only a thin coat of oil protecting everything. at the small engine shop i work at, if an engine is siezed there not usually much to do. we free it so it turns and then run it. its a crap shoot. ok i just reread your post, im thinking it may have been as simple as a slightly open intake valve, a carb leaking into the cylinder, and now a fouled plug. give it a try and see what happens (take off the air filter and replace the spark plug, i think its an ngk bpr5es) see if that helps.
Reply:Typically Honda GX engines are pretty much bullet proof, but the GX340 and 390's need valve adjustments more regular then the smaller Honda's. I would pull of the valve cover and check to see if you have a broke rocker arm or bent push rod. If it pulls hard when starting or kicks back then it's usually valve adjustment problems. I'm pretty sure the valve gaps are .010" exhaust and .008" intake at TDC. If you need parts try gxparts.com. I'm not affiliated with them but they have about the cheapest honda parts around.After rereading again it sounds more fuel related (agree with LuzRD) if it's fuel you can try fresh gas and drain the bowl of the carb and get a fresh spark plug.Last edited by toolshednc; 04-26-2007 at 11:25 PM.
Reply:Originally Posted by TPnTXI've read a few posts about small engines and Honda in particular. I have a GX340 11hp that runs my 4000psi pressure washer. I think it froze up. One day I couldn't pull start it. I didn't know if it was the pump or the engine so I pulled really really hard on it and it finally turned.I pulled the pump and it spins fine. The engine will only start if I hit it with some starter fluid. When it starts I can't rev it up at all. It just dies. So I'm thinking I it needs to be rebuilt.I've rebuilt the top end on a honda atv engine before. I'm wondering if it's worth tearing into on this engine. Itslike 700.00 for a new one. Anyone ever rebuilt one?
Reply:thanks for all the info.Being stuck is the big mystery. I'm kinda doubtful you and "unsieze" an engine with the recoil so I'll look further at the valves.At this point I drained the bowl, cleaned the filter and removed the old prefilter, I even tried with no filter.I could try a new sparkplug just for grins but I figured usually if its running at all it aint the SP.This is a monster Pressure washer. The pump is a Blue Cat and it'll peel the paint off.
Reply:Definitely try the new sparkplug.  It's not unusual for a small engine to fail to develop power if the plug is marginal.  I don't know about just free revving, but I've had small engines that would not develop power due to a bad plug but would idle.  That's a little different from the symptoms you describe but it might be worth a try as you say.
Reply:LuzRD,Russell Thompson over at NR-Racing told me that the Hondas were ball bearing shafts. You said that these things had no bearings. Did I misunderstand something? Hoping he is right since I just bought an engine from him. Waiting for delivery now. Guess I will find out soon.Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:joker im at work now and can check the software, and the gx340 does in fact have bearings. sorry bout that!! i thought it was one of the ones with no bearings.
Reply:LuzRD,Do me a favor and check on the GX200 too. That is the one I ordered.Thanks!Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:if you need to buy one order it from small engine warehouse. i have ordered at least five small engines from them. NOBODY beats there prices! www.smallenginewarehouse.com
Reply:joker i just checked for you, and the gx200 also has bearings.i guess im just more familiar with the lawnmower engines sorry again for the goof up = }
Reply:Joker11 - The GX200 you bought will definately have ball bearings for the crankshaft.  In our racing, some folks have been known to cheat and use non-stock bearings with looser clearances, or even ceramic bearings.  All of mine have the stock NTN bearings and we have added an extra side plate gasket to releave some of the crank side play.  The rod bearings are as cast into the rod and the engine uses dip oiling.  We race using 400cc of racing oil, but Russell will tell you to use Mobil1, and that works great too!  Ask him for his recommended quantity; we change ours after every track session, but you'll want longer intervals, so will probably need to add more oil just for the safety factor.  The engines do come with low oil shutoff.BTW, I think I can put one of these together in my sleep, and probably have Richard
Reply:I got the motor. The kid is going crazy waiting to put it to use.I am planning this ALL for him. I can't wait. He needs to get into figuring things out and it's about time. He is going on 10years old with no mechanical skills yet.Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:I thought you were replacing an engine?  I bet the kid wants a Kart DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:Actually we are building an ice chest cruizer.It will seat 4 people and travel at low speeds, all torque. I gotta get the sprockets set up right for this one.No, he doesn't need a kart. He has a brand new 07 Honda ATV and a little stand up motor scooter to ride.We WERE going to put the engine on the stand up scooter, but he changed his mind. I dunno. I may do it first anyways and make it a dually in the rear. We can move the engine around for different projects just for chits and grins.Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:Hello,I am wondering if anyone can help? I have been offered a Honda gx340 welder genny. My neighbour bought this for power when he was building his house but it has stopped working. It starts first time and runs sweet but does not produce any power. He has pulled out a few cable and not reconnected them which does not help and he has changed the capacitor which is not the correct one. Honda said he had to change the whole generator side which costs 375. This was over the phone though. Is it worth bothering with? Any info much appreciated Thank you  [email protected]
Reply:"I think it froze up. One day I couldn't pull start it. I didn't know if it was the pump or the engine so I pulled really really hard on it and it finally turned."did you unload the pump head? With the water turned on the pump will load up if the engine doesn't start first or second pull. Pull the trigger on the wand to release the built up pressure and you can give another couple of pulls , then pressure builds again. This is normal for a lot (not all) pressure washers. My new BE does this, my old home built does not.Sounds like you may have some other minor engine problem as well, however, as another poster suggested, if an engine is  locked up a pull on the recoil is not likely to unseize it.
Reply:This thread is over three years old. I'm sure he found the problem years ago. Millermatic 251Spectrum 300 PlasmaEverlast PowerTig 250EXEverlast PowerCool W300Harris / Victor OACraftsman 13 Speed Drill PressProTools Air/Hydraulic Bender48" BrakeCompressor, Notchers, Grinders, etc.
Reply:never know, might still be pulling on that cord
Reply:With a VERY sore arm.