First remove drain plug from bottom of engine housing. There should not be any oil come out.

If so, you have a bad rear crankshaft oil seal.  drain and let stand an hour or day and reinstall drain plug

Keep nose up and oil out of engine, you wouldn't have to replace oil seal

 

Remove spark plug, put spark plug wire back on.

Then clip a wire from bottom of spark plug and other end to tiller frame.

I usually take Front Starter assembly off and turn engine over by hand.

You should see a spark.

  Also check that the piston that it is going down as the magneto clicks or sparks.
If not you need to adjust the magneto adjustable coupler.

 

Carburetor settings should be good if no one has touched the settings since the last time it ran.

However the settings are: The top back idle screw should turned all the way in clockwise

Then back out CCW 1-1/2 turns.

 

With All this it should start.

If not then the problem is deeper.

Could be clogged cylinder block ports going to manifold.

Clean all 3 ports, - pencil size hole in middle of the 3 holes should be clear.

Carburetor not getting gas fumes up to cylinder block.
Check gas line is providing gas.
Check fuel sediment bowl is clean and providing gas.

Repairs / Rebuilds done by You

Tilotson Carburetor settings:
Float should be 1-5/64" fron top of body gasket to top of float with carb upside down.
Idle Screw Adjustment - Turn CW all the way in, then back out CCW 1-1/2 turns.
Throttle stop - Turn screw CW in until choke starts to open. Then go CW 1-1/2 turns more.

Zenith Carburetor Settings:
Float should be 1-5/32" from throttle body gasket to top of float.
Idle Screw (Top Screw) - Turn all the way in CW then back out 1-1/4 turns.
Main Jet Screw (Bottom Screw) - Turn all the way in CW, then back out 4-1/2 turns.
Run engine at half throttle - Turn main Jet Screw both ways until change in speed.
Set screw for middle of the 2 changes

Magneto
Brown Fiber Drive Member - 0.010" gap

Points Gap
    For Fairbanks Morse - 0.020" gap
    For Edison Splitdorf -  0.015" gap

Spark Plug should have a 0.027" Gap

Moving
Units with No Reverse - Low Speed pull control rod backward
                                       - High Speed push control rod forward

With Reverse - Low Speed  Right side of Transmission - Put in Upper Notch
                        - High Speed - put in Lower Notch

Speed Low Gear at 2400 rpm 3/4 mph

Tiller Shaft 245 rpm

Hood Height - 1" Clearance bottom of hood to ground

Tire Pressure - 10 to 12 pounds

Air Cleaner - SAE 30

Fuel Tank Mixture - SAE 40 Straight Mineral Oil (Aviation, Raacing)
    Mix 8 ounces to 1 gallon of gas - Holds 8-1/2 to 9 quarts - Runs 4-5 hours

Fuel Tank - 8-1/2 Quarts

Air Cleaner - SAE 30 - 5 ounces

Air Cleaner Hose - B1-6 No Reverse 14" Long
                                  B1-7 Tank Mounted 18" Long
                                  Units with Reverse 21" Long

Transmission and Tiller Housing share SAE 90 Gear Oil - 6-7 pints

Throttle Cable - Units with No Reverse - Wire 72" Sheathing 66"
                              Units with Reverse - Wire 82" Sheathing 79"

Engine:
Displacement 22.97 cu in
Compression Ratio 6.1 to 1.0
Compression Pressure at 1000 rpm 110 to 115 psi
Maximum Torque 14.5 ft lbs at 1350 rpm
Clearance between piston and cylinder wall 0.007 +- 0.001"
Piston Compression 60 psi