Gas mix is 3.2 oz per gallon what is size of fuel tank?

carb might be leaking fuel into the crankcase and thinning out the oil.

half plus ,6 oz to a gal or your mix or 2.6 from the 4oz and 1 gal of gas

Mixing
RatioGAS:OIL UNITED STATESOIL per 1 U.S. GALLON Gasoline
(128 oz.) *INTERNATIONALOIL per 1 IMPERIAL GALLON Gasoline
(160 oz.) *INTERNATIONALOIL per 1 LITER Gasoline
(metric) 32:1 4 oz. 5 oz. 31.25 mL 40:1 3.2 oz. 4 oz. 25 mL 50:1 2.6 oz. 3.2 oz. 20 mL

Two cycle engines run on a mixture of gasoline and oil. Each engine type is designed to run on a specific gas-to-oil mix ratio.
IMPORTANT: Use only oil that is labeled for use in "Two-cycle" or "Two-stroke" engines. Home Depot and other stores now have "premixed fuel" of gas and 2 cycle oil.
To mix two-cycle fuel, start by putting correct amount of oil in gas can. Then slowly add correct amount of gasoline. Do not try to mix gas and oil directly in gas tank of equipment.

IMPORTANT: Do not use any fuel that is over 30 days old. Do not mix more fuel than you are likely to use in a month. Old fuel can gum carburetors and prevent starting. Always use fresh fuel.

The chart below shows correct amount of oil per gallon that each mixing ratio requires. Expect that yours will be between 32 gas to1 oil and 50 to 1. 32:1 and 50:1 are most popular.
Ratio GAS:OIL UNITED STATES OIL per 1 U.S. GALLON Gasoline
(128 oz.) *INTERNATIONAL OIL per 1 IMPERIAL GALLON Gasoline
(160 oz.) *INTERNATIONAL OIL per 1 LITER Gasoline
(metric) 32:1 4 oz. 5 oz. 31.25 mL 40:1 3.2 oz. 4 oz. 25 mL 50:1 2.6 oz. 3.2 oz. 20 mL

2.56 oz of oil per gallon is the exact amount. Dump 3 oz. of oil in a gallon gas can and fill it up. Then mark the can so you don't mix it up with lawn mower gas.

Gas Fuel Mix 5 oz of 2 cycle oil per gallon of gas

there is usually a fuel/oil ratio (i think yours is 50:1) you must buy the 2 cycle oil and mix it with gas at the ratio reccommended by the manufacture. the bottle may say 6 oz per 1 gallon = 50:1 So 1 bottle of 2 cycle oil for every gallon of gas. mix them in a proper fuel can. then let the cutting begin.

The standard mix for most chain saws is 40:1 that's about 3-1/4 oz per gallon.

Your tank is 19 gallons and you get about 18 miles combined miles per gallon. Thats city and highway. Highway is around 21 and city is about 16.

Yours is not a current model and I did not find a manual. The following is an excerpt from a 26cc MightyLite Blower/Vac UT08550/UT08951 "Operator's Manual":
This product is powered by a 2-cycle engine and requires pre-mixing gasoline and 2-cycle lubricant. Pre-mix unleaded gasoline and 2-cycle engine lubricant in a clean 1 gallon container approved for gasoline.
Recommended fuel: This engine is certified to operate on unleaded gasoline intended for automotive use.
Mix Homelite Premium Exact Mix lubricant with gasoline according to the instructions on the package. If Premium Exact Mix lubricant is not available, use a high quality synthetic 2-cycle engine lubricant, mixed at 2.6 oz. per gallon (US).
Do not use automotive lubricant or 2-cycle outboard lubricant.
NOTE: Premium Exact Mix fuel mix will stay fresh up to 30 days. DO NOT mix quantities larger than usable in a 30 day period.
PREMIUM EXACT MIX (50:1)
GasolineLubricant
1 gallon (US) 2.6 oz.
1 Liter 20 cc (20 ml)

1 quart fuel:3/4 ounces of oil = 1 Gallon fuel:3 ounces of oil or slightly less than 43:1. Not what a current manual recommends.
If properly adjusted your blower will operate fine on 50:1 regardless of what the manual reads. HTH
Lou