Just blowing some white smoke when cutting some high grass otherwise none. May be the head gasket since in the process of removing the top to fix some things, like recoil, may have loosened the head bolts. Did tighten but no torque. Well maintained. Replace head gasket?
TORO SR-21S, Self-propelled, 6.5 HP, BS,15 - 20 years, 1st owner - White smoke
- Thread starter W1D2C
- Start date
Tiger Small Engine
Well-Known Member
- Joined
- Dec 7, 2022
- Threads
- 1
- Messages
- 703
Sounds like an L-head Briggs and Stratton. Simply take a wrench and check cylinder head bolts for tightness, and tighten evenly. Just because it is blowing some white smoke while only cutting high grass does not necessarily mean head gasket needs to be replaced. So no smoke while cutting under normal conditions? How much does it smoke when it does smoke? Did it just start smoking?
bmoore2620
Forum Newbie
- Joined
- Jun 29, 2016
- Threads
- 0
- Messages
- 3
Just something I ran across a few times on the Briggs L head engines, usually on 10-12hp. The valve cover on the side of the block was causing oil to pass through to the carburetor when the engine was put under load. As long as it was just running it was fine, but the moment I engaged the blades it would blow white smoke bad, and usually die. I took the air filter cover off and the carburetor was sitting with oil in it coming from the rubber hose that connects to the valve cover. Hope this helps.
- Joined
- Feb 19, 2020
- Threads
- 79
- Messages
- 10,274
Toro SR-21S (20043 or 20494) Briggs L-Head. 15-20 yrs is a lot of age. Probably worn rings or worn valve guide(s). I had worn exhaust valve guides to cause these engines to smoke. But as bmoore suggest it is likely excess oil in the breather causing the problem from an over pressurize crankcase.