This is a very common problem. The issue is called "Hunting"
The carburetor is dirty and some of the small passages are restricted and are not letting enough fuel through it.
Most likely the problem you have is that the carburetor is restricted or plugged because of fuel that was left in the the carburetor while it was stored. Fuel CANNOT be used if it is over 30 days old.
In many cases the carburetor should be removed and cleaned and rebuilt with anew carburetor repair kit.
Even if an engine is run dry, there will still be 10 to 12 drops of fuel left in the carburetor. This is what turns to gum and varnish and dirt and restricts the passages in the carburetor. Also keep in mind hat even if this is a BRAND NEW unit, you can still have this same carburetor problem. This is because of the fuel that the factory puts into it when thy are testing it. They then run it dry before shipping it. But there is still some fuel in the carburetor.
I do have a possible Quick fix for you, but you must use what I tell you.
DO NOT USE regular CARBURETOR CLEANER such as GUMOUT or something similar. These will ruin the rubber parts of the carburetor.
HEre is the possible Quick fix.:
There is one good thing you can try. It is called "Mechanic in a bottle". It is usually available at WALMART or many autoparts stores. Even some Mower repair shops. We carny it at my store.
It is designed to help clean the carburetor without damaging the diaphrams and rubber parts like regular carburetor cleaner. Click on this site and it will tell you all about it.
This helps sometimes, but other times it does not.and the only solution is to to clean and rebuild the carburetor.
It is available t Home Depot and good mower shops.
It is also available at Amazon.com
The mechanic in a bottle is NOT a conventional carburetor cleaner.
It actually breaks down the varnish into it molecular components and it completely dissolves. It DOE NOT clog up the jets as conventional carburetor cleaners do. Conventional carb cleaners just loosen the varnish and the varnish particles will go into the jets and filters and clog them up.... usually causing much more problems that was originally there. The conventional carb cleaners also will loosen the "GUMK" that has formed in the gas tanks and cause all of that gunk to go through the carburetor as well.
The Mechanic in a BOTTLE is a completely revolutionary product that will in many case alleviate the need to tear the carburetor down and rebuilt it..... unless there is mechanical wear and tear that would require that parts be replaced.
In addition, the special formula actually is designed to soften and restore the rubber parts in the carburetor such as the needle and seats and gaskets.
Mechanic in a bottle is NOT a cure-all but it can help customer get going in many cases without them having to tear the carburetor apart. If the customer is NOT mechanically inclined, it might save them a trip to the repair shop.
Yes I was very skeptical about this product when I first was introduced to it, but the Distributor demonstrated it and we have tried it on many occasions with terrific results.
Varnished carburetor? Fuel gone bad? Water in the tank & carburetor
causing corrosion from ethanol? "FIX THE UNFIXABLE" Mechanic In A
Bottle removes all varnish in the fuel system without having to remove
the carburetor from the machine. Add to your gasoline and you will be
able to clean varnish and carbon.
together since the fuel has deteriorated. An octane booster is added to
replace the lost octane in the decayed fuel. We do not use any metals in
our formula to increase the octane.
including the combustion chamber, piston(s), rings and valves.
rejuvenate and protect the rubber gaskets and seals that may have been
dried out from ethanol. After the fuel is burned in the combustion
chamber, a synthetic lubricant remains to lubricate the entire upper
combustion chamber, such as piston rings and valves.
Poor Running Engine:
No detrimental effects if overdosed.
Mix 2 ounces of Mechanic In A Bottle (MIB) to 1 gallon of fresh gasoline.
Start engine and run for at least 10 minutes. Let engine stand for at least
8 hours before restarting. Continue use of mixed MIB fuel until gone. Use
Ethanol Shield all the time to prevent fuel related problems.
Non Running Engine:
Add 4 ounces of Mechanic In A Bottle (MIB) into an empty fuel tank and
prime the MIB through the fuel system into the carburetor. Wait at least 8
hours before draining contaminated MIB from the fuel system and
adding fresh fuel mixed 2 ounces MIB to 1 gallon of fresh gasoline.
Severely contaminated fuel systems let stand overnight or repeat if
Mix 1 ounce of MIB to 5 gallons of gasoline.
This is a fuel additive not a replacement for 2 cycle oil.
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