Small Engines (Lawn Mowers, etc.)/oil leak


Sir, Started my 18.5hp B&S and it started throwing oil.Seems to be coming down the shaft of the double pulley. Immediately shut it down.It still contained most if its oil. Did not leak when shut down. Along with what might be wrong-any idea what it might cost to repair or should it get another piece of crap B&S. I say this because this is the second one to crap out. First one blew hole in side of engine 2mos after end of warranty period. Appreciate your time and knowledg.

Gas in the oil?  Maybe, but not as common on 18.5 engines.  Easy to check the carb and even easier to just smell and feel the oil...if it smells like gas and is really thin then gas got in the oil.

Loss of crankcase vacuum?  Easy check with a vacuum gauge.  While Briggs does not publish vacuum or compression specs the main point of the test is just ensure the crankcase is NOT developing positive pressure and causing the oil to be pushed out of the seal(s).

While no engine is perfect, there are various reasons I prefer Briggs over any other engines.  There are better engines out there but there are cons as well with those engines.  If you plan on staying in the US then stick to an engine that has good support in the US...that's Briggs.

Let me know if the oil smells like gas is really thin.

Small Engines (Lawn Mowers, etc.)

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Eric A. Jones


Lawnmower Repair . Certified Master Service Technician from B&S. Have 23 years experience on B&S, Lawn Chief, Weed Eater, Echo, Peerless, Wheel Horse, Snapper, Atlas, MTD, McCulloch, Homelite and many other numerous brands. Specialize in electrical repair.


Born and raised in the midwest. Started tinkering with engines when I was about 14 on my Suzuki RM-80. I began lawn mower repair at a small hardware store. I knew absolutely nothing. I read lots of repair manuals and met an older fellow who taught me many lessons. I continued working on small engines through high school and paid my way through college working on mowers at the same hardware store. Decided to get away from the midwest and mower repair so I joined the Air Force. I repaired air traffic control electronic equipment and ended up in Hawaii where I got a part time job at Small Engine Clinic. I gained a lot of experience from the Small Engine Clinic and had a blast repairing small engines. I then took the Briggs and Stratton Master Service Technician test and earned my MST. I then traveled to Wisconsin where I attended the factory update training seminar and received formal training. Continued working on mowers part time as I completed 20 years of military. Retired from the military on a Friday and continued in the lawn and garden industry the next Monday.

MAS Aerospace Operations BA Mathematics AAS Electronic Communications AAS Electronic Technology

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