Head Gaskets have nothing to do with Oil Consumption.
On these Briggs & Stratton engines, head gaskets certainly have everything to do with oil consumption and is the most common reason for oil consumption or usage. The second most common reason for the oil to get low would be leakage and that would typically be around the Briggs & Stratton very common quick oil drain valve which works fine but eight and a half out of 10 of them are not installed properly because they are usually if not always installed by the machine manufacturer and not by Briggs & Stratton when the engines leave the warehouse.
It's my belief that Briggs ships all the engines with the standard pipe plug in them but includes that as an option for some of them or the manufacturers order them are already have them and they are the ones that take it out and install it because on the very basic low budget machines they want to save the money and in some applications it just doesn't position itself well to use that and some engines have more than one drain so it can go on either side even though that's not common.
But these things are typically finger tight and you can remove them by simply using your fingers. Like I said it's about 8.5 to 8.7 out of 10 if you survey and see enough of them.
But back to head gaskets, on the Briggs when the head gasket blows it absolutely consumes oil and burns it and when the head gasket blows enough it will visibly show out the exhaust even so much as to look like a mosquito fogger so much that you can't even see your house through the smoke.
This is because these engines are not like somec ar engines where the combustion chamber and the piston area is not connected to or sealed from the lifter galley.
On these engines the piston and combustion chamber is is right next to the lifter galley with only a small thin and gasket to seal it off and a poor design with a long space and not anything over barely adequate clamping force to keep it sealed.
Then, more importantly than the design because cars do have access to the lifter area through the pushrod holes but they are typically four six or eight cylinder engines.
Those engines create constant vacuum when they're running because you have multiple cylinders and pistons timed in different places throughout each revolution of the engine.
These little singles especially and even twins don't have enough to smooth it out so they are very choppy and every time that piston goes down it basically pressurizes the crankcase from the air cup underneath the piston then when it goes up it creates a vacuum in the crankcase from the same movement.
This is why these engines can use this pulsating fuel pump we're talking about. You could not use such a thing on a car or anything that's smooth because you would not have a pulsation, you would only have vacuum.
So these engines are constantly puffing in and out and sucking and blowing on the dipstick tube, the valve cover, the crankcase etc. When the gasket blows.... Things stop staying where they're supposed to be... like oil.
You have compression leaking over into the lifter galley which is pressurizing the crankcase which gets your oil black and nasty and pressurizes the crankcase which can not be good for seals not leaking etc and can cause the breather to leak some and oil go back into the carburetor but more importantly...you have it trying to suck oil at the end of the power stroke right after the explosion as the Pistons going down it's creating a vacuum at least at the end and trying to suck oil through the lifter galley cracked head gasket area back into the combustion chamber.
It's just like a back of fourth tug of war fight if you could film it and slow it down.
But anyway, even with a Briggs single, when the head gasket goes, it continues to widen that little crack in the middle of those two head bolts and eventually it will be blowing a huge cloud of oil smoke.
A blown head gasket can you use 6 or 8 oz easily in 30 to 45 minutes of mowing. Some use less and some use more because when you take them apart some will only have a small like carbon track line between the two areas while others will have 3/8 of an inch he wrote it away.