I have a Honda EM2500 generator which I don't use often but try to start a few times a year. Always has ethanol free gas. When i tried to start it today gas was dripping out of air cleaner. I drained the carb and cleaned the bowl and tried to start again with air filter off. It started and ran poorly with smoke belching from exhaust and then gas staryted gushing from intake side of carb. Took off valve cover and push rods seem to be moving up and down. Looking for advice. And when i say gushing, I meant exactly that. Would not have guessed there could be enough gas in carb bowl for the amount I saw. Appreciate any advice. Larry
I should have added that it pulled harder than I thought it should.
I'd say your needle valve isn't closing. The float could be full of gas or have a hole in it or stuck and it could be that something is between the seat and the needle valve. Was there a lot of crap in the bowl when you took it off and cleaned it?
I'd say your needle valve isn't closing. The float could be full of gas or have a hole in it or stuck and it could be that something is between the seat and the needle valve. Was there a lot of crap in the bowl when you took it off and cleaned it?
I did not catch the gas when removed the side drain plug to drain carb but there was no schmutz in the bottom of the bowl when I took it off.
#4
Scrubcadet10
float/needle is not stopping fuel flow into the bowl. rebuild or replace carburetor.
Do you have the model of the engine or generator, i'm not finding any breakdowns for the EM2500
It's the GX160. pretty old but I found a breakdown on ereplacementparts. Plenty of carbs on Ebay for cheap. I've never had much luck rebuilding carbs and had pretty good luck with cheap ebay carbs so I'll probably go that route. Any ideas why it would pull hard? Probably been 6 months since I ran it
The reason it would pull hard is hydrolock. Raw gas on top of piston.
You could remove that carb and then remove the bowl and you will probably find that the float is stuck in the down position. You don;t have to rebuild your carb just turn the carb upside down back and forth and gett the float swinging. You might clean the needle and seat while you have it off and on the work bench. You need to check you oil in the engine. It might be gas contaminated and thinned out. Sometimes this can be seen as a high level on the oil dipstick. Also do a sniff test of the oil.
Also most all Honda gens have a fuel petcock that is intended to be turned off when not in use.
You have to be careful when getting replacement clone carbs that the choke lever is correct. (look at pictures on fleece bay then compare to what you have now, a standard carb usually will not work because the choke lever is different on a gen engine due to the configuration of the carb breather layout)
You
#7
Scrubcadet10
Honda carbs use a rubber (viton) tipped needle, so the needle would only need replaced.
Good call Forest#2! I figured while I was waiting for the new carb, I would drain the oil and see if there was gas mixed in. Took out dipstick and had a gusher or what looked like mostly gas. I had neglected to close the petcock last time I ran it. Usually I close it and let it run the gas out of the carb but apparently forgot to do that. The float was moving freely and not filled but probably will put the new carb on anyway since something was obviously wrong.
Read what scrub cadet says about just replacing the needle. Also clean the seat with a Q-tip BEFORE installing the new needle.
If I find a needle that's not holding 3 lbs pressure testing first:
Sometime if it's a vitron tipped needle I can take a magnifying glass and carefully inspect the tip and see what looks like hair or small pieces of dried crud, use alcohol and carefully with a q tip wipe the crud, clean the needle seat and good to go.
If you have a mityvac 8500 pressure/Vac that will do pressure you can invert the carb upside down so as the float weight holds the needle seated and it should block 3 psi pressure. If won't block pressure at 3 lbs or up the needle needs replaced. (and the seat cleaned)
Do not be surprised if a China clone carb does not operate correctly, (rolling the dice) is WHY I mention just replacing the needle.
Sometimes I can remove parts from a Clone such as needle and install it into the OEM carb and all ok, but I do not guess at such, I do the described pressure test flipping the carb float up and down with the carb upside down just letting the floats weight operate the needle.
A blood pressure bulb with a 0-5 lb gauge can also be used.
Follow up: I drained the oil/gas from the crankcase and put 20 oz of clean 10/30 oil in. Put the old carb back in after spraying all the openings with carb cleaner. Started up easily but after 30-60 seconds started to blow smoke. Drained oil and put more fresh oil in thinking that there might have been enough of the gas/oil left to cause a problem. Still smoked though after 5-10 minutes it smoked much less. Still more than I like. I haven't used this genny much other than strting it up a few times a year. Never use anything but ethanol free and usually put a dollop of stabilizer in for good measure. It did not run for more than 60 seconds when the case was full of gas. Could the piston/rings/cylinder have gotten damaged in that short of a time? I did have the valve cover off during this whole process and did not check the gaps butdid wiggle them and felt like a normal amount of play. Not tight or very loose. I put a new gasket under valve cover. If that was leaking, would it cause smoking? Again, I appreciate any advice. Larry
When it started smoking was the smoke blue or black, like black soot.
The reason I ask is oil smoke is blue, running rich will be black soot.
Was the engine running smooth?
Does that unit have the auto idle, where it will idle if a load is not placed on the unit and a switch set to AUTO?
If it's blue smoke just let it run. The crankcase was overfull with contaminated gas before and it has caused wet carbon/oil in the muffler and on top of the piston. It should clear itself after about maybe 30 min's. (engine and muffler has to get hot)
If it's black soot, shut it down, your needle/seat is leaking or the choke is stuck on, and the engine should be running rough if it's getting too much gas through the carb.
When you kill the engine turn off the petcock immediately or turn off the petcock and let it run out of carb gas.
Well, I had put exactly the specified amount of oil in but it was reading a bit high on the dipstick, so i drained out an ounce or two and smoke is gone. Thanks to all who offered advice and especially to Forest #2 who diagnosed the gas in crankcase.
Sure, if you live by the ocean or maybe store this unit outside. Big temperature swings daily? I would pull the plug and fog the cylinders with Stabil's fogging oil. Standby generators sit for untold days.
Not exercising gasoline operated standby by emergency generators every once in awhile is usually what makes them not ready to go when needed. Ethanol fuel is a no-no also
Before storing I usually do the following procedure so as to prevent/reduce possibility of a metal gas tank rusting and to keep the carb from drying out and making gunk. Turn the petcock off at the bottom of the gas tank and run the engine until it runs out of fuel, remove the gas hose from the carb or petcock and drain gas down to approx 1 gallon, then dump in 1/4 quart of ATF oil, enough to color the gas red, re-connect the gas lines and remove the carb bowl drain plug and let the ATF mixed gas go to the carb and when ATF starts flowing out the bowl drain re-install the drain plug and let the carb bowl fill.. Remove the spark plug and add spoonful of ATF slow crank the gen and then re-install spark plug and leave plug wire off. (or use the fogging oil mentioned above)
I do the same procedure also for plastic gas tank gen's.
When the gen is needed or to test later just add gas, usually 4 gallon to the existing in the tank, crank it up and let it smoke for awhile. It will run ok with the ATF/gas mix, just little bit of smoke at first.
Diesel, propane and Natural gas gen's are normally more reliable when coming out of standby storage.
Some of them older model Honda gens used a metal gas tank and if not taken care of will rust severely.
Also it's recommended to remove the electrical load from the older model Honda gen's BEFORE killing the engine so as to reduce chance of ruining the very expensive AVR. (Automatic Voltage Regulator) The reason why such is recommended is the Electronic voltage regulator tries to compensate for the drooping voltage/current of the load as the engine is dying.
Some of the AVR's for Honda emergency gens is in the $300 starting area. (and no warranty for electronics when purchased from a Honda dealer)
