028 Gas running out of muffler

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blel

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I get gas practically running out of the muffler on my 028. If I can get it to run, it smokes like hell. Cleaned carb with new kit but no difference. Any ideas?
Thanks
 
Leaking float valve in the carb would be my guess. Possibly a plugged fuel tank vent so it's pressurizing too much and forcing fuel into the carb.
 
Other possible causes

Sticking inlet needle (varnish, trash or worn)

control lever not set right

metering diaphragm turned wrong way or against carburetor body
instead of gasket. The bump contacts metering lever.

The pump diaphragm is against carburetor body and gasket against cover,
opposite from metering end.

I am looking at a diagram of a Tillotson HS carburetor, most of CS
carburetors until strato-charged that I have seen are similar,
never seen a float on a chainsaw carburetor, some antiques may
have them.

I usually ID carburetor, download diagram from carb company & use it
for reference on reassembly.
 
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Float needle, inlet needle, same deal (yesh...I know there's no float in chainsaw carbs).
 
I took the carb apart again, checked location of gaskets, diaphragms, etc. This is a new carb kit. Checked vent hose. Still same problem. It's strange cause gas will start coming out through muffler while I'm cranking it over but it won"t usually start unless I take plug out and prime it. Then it will only run until that gas is used up, a few seconds. This all started after I ran out of gas When I refilled it the problem started. Was running fine until it ran out of gas. I hate to take it to the shop but might have to.
 
Leaking float valve in the carb would be my guess. Possibly a plugged fuel tank vent so it's pressurizing too much and forcing fuel into the carb.

Many tank vents don't allow any pressure to escap, allowing considerable pressure to build up in the tank. They only prevent a vacuum. It's the function of the needle in the carb to stop the fuel flow. Tank pressure should not be able to over come it.
 
The one thing I didn't replace is the little plug on the metering side of carb. Could this have anything to do with it?
 
I doubt this has anything to do with your problem, but the 028av I have had an issue with the choke flap getting sucked shut... spring was too weak.
 
I doubt this has anything to do with your problem, but the 028av I have had an issue with the choke flap getting sucked shut... spring was too weak.

Thanks but in my case you can see the gas coming thru the muffler when you are just cranking it over.
 
Most cases of carbs flooding before the engine starts is caused by the inlet needle either having debris stuck between it and the seat as can happen when a saw is run dry, crap gets drawn into the carb. Also if the metering lever is set too high keeping the needle from seating or in some instances the metering lever may have a fork in the end where the metering diaphragm metal button is designed to fit into, if that button is left sitting on top of the metering lever instead of being hooked in, the carb will flood.

Pioneerguy600
 
My old 028 would spray alot of gas out the muffler as the ignition coil went, changed out the coil and mine runs like a champ it was just not getting enough fire

dont know if this helps

Im the dumb new guy
 
Maybe bad coil

My old 028 would spray alot of gas out the muffler as the ignition coil went, changed out the coil and mine runs like a champ it was just not getting enough fire

dont know if this helps

Im the dumb new guy


Same here - - Pulled most of my hair in out in large clumps chasing what I thought was a carb problem until Fish pointed me in the right direction. Replaced old coil with new electronic ignition and she ran like a champ. Old coil had spark, just not enough.
 
My money is on the metering needle issue. Either the metering lever is bent up too high, or the needle itself is faulty. I've had the rubber end on the needle stick in the seat and break off (old needle), then it holds the needle open during operation. This caused gas to run out the exhaust. This happened after I rebuilt the carb. But an improperly set metering lever can exhibit the same symptoms. The coil issue is also very feasible. Hone in on those areas and you should have it.
 
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