I recently changed the blade on my 22" Yard Machine push mower. It is a 22" blade. A bunch of oil spilled out of it when i turned it upside down and it was replaced. Now the chord on my mower is difficult to pull if i can pull it at all. I took out the spark plug and cleaned it off and also shook out the air filter and loosened the blade a bit. What might the problem be?

Check to make sure your blade is not bent first take the spark plug out for safety then by turning the mower over on its side. Now turn the blade and determine if the blade is rubbing the deck or if the sound is in the engine if it is in the engine it will probably be a bent crankshaft. If it is the blade bend it back to 180 degrees perpendicular to the crankshaft. If it is the crankshaft. it will be a costly repair that could cost more than the original cost of the mower. Buy a used one at a garage sale,yardsale or other source make sure to test any used product before buying.

You can use regular SAE 30 weight oil from the auto parts store. If you use multi-viscosity, make sure it is synthetic, otherwise use straight SAE30 oil.

Most normal push mowers require 20 ounces of engine oil. I recommend that you use only SAE 30 oil and try to use synthetic.

i just looked up Quattro mower they are a 4 stroke engine and yes i would buy a 22 inch blade but be sure it fits this mower PS go to wall mart and check out their blades they are reduced now.

MTD has made many 22" machines over the years. Please repost your question indicating the model #

From what you describe it sounds like the line may be tangled, remove the rewind housing in order to inspect the line up close.

Most of these machine will have an oil drain plug under the mower deck near the center of the blade. 80 to 90 % of them are a 3/8" drive female plug that can be removed with a ratchet and a short extention.
When you put it back in it is a good idea to clean it well and wrap the threads with 2 or 3 layers of teflon tape

Sounds like it time for a tuneup. Air filter changed, Spark plugs replace and oil changed, plus sharpen the blades while you are at it.

when you unscrew the oil cap is should have an oil level mark on the side of it.

the oil drain plug is underneath the motor by the blade you can use the socet wrench to open it