Outdoor Power Equipment and Small Engines - Briggs and Stratton 17 HP oil blown into carb from breather

Hello.

I have a 2000 Ariens 1742 EZR mower with a Briggs engine model (17HP) 311777 with overhead valves. Under load (blade engagement) there is some serious oil blown into the carb from the breather. I have changed the oil and filled it with the correct amount. I have also just replaced the breather which did not correct the issue. It also seems like exhaust comes out the breather as well. I have read a bunch of posts that talk about bad rings, gaskets etc. Are there any tests or procedure I can try to determine what the problem is before I take it down? Any information would be greatly appreciated!
Thanks in advance.

You can do a compression test to determine if you have compression loss from the combustion chamber into the crankcase = cracked head, rings, blown head gasket.

If this started suddenly, it's likely a blown head gasket. Rings would be a slower process and likely would involve some oil burning.

The most conclusive test would be a leakdown test. I think I would have a shop do that one for you.

I checked the compression. It get up to around 90 PSI pretty quick. After I stop cranking the guage bleeds down to zero fairly quickly. (within a couple minutes) I also notice pretty strong suction and blowout on the dipstick tube with oil spitting out if I dont cover it while cranking. Not sure if that is normal.

Sounds like your gauge may not be working correctly.
I agree that a leakdown test is the way to pinpoint the problem. You might pop the valve cover and check clearance and valve operation.

Most likely the head gasket let go between the cylinder and the area where the push rods pass thru very easy to remove head , break will be easy to see, common probelm with b/s ohv

Thanks, I will check out the head gasket. I am hoping its not something more serious like rings or a complete rebuild!