I was merrily mowing my front yard when the mower suddenly lost it's power. It still ran, but putt putted, and if I went in to grass it couldn't handle it. It's a basic Murray push mower w/ a 4 hp Briggs & Stratton. Been fine for years. I cleaned the air filter and changed the plug, same problem. Interestingly, if I tilt it back, it picks up momentum, but slows down again when I put it back down. I took the blade off earlier today to sharpen it. I'm wondering if maybe some garbage got in the fuel line. Any insights would be appreciated.
Thanks

Bill T, June 2009

Hi There,
You may want to checkout the fuel bowl. Sometimes the little filter gets a bit clogged with grit, and that may be slowing the engine down. Also have a look at the magneto on the flywheel. It may need to be cleaned if its rusty or otherwise mucky. But that would also affect the engine starting smoothly.

Mike, June 2009