TORO ZERO TURN MOWER WON'T TURN OR MOVE ONE WAY

Roy Cagle

• 1545 Answers
• Posted on May 15, 2011

SOURCE: The starter won't completely turn over even though

Sometimes on the Briggs and Kohler engines, the compression release fails to operate at the proper time or is malfunctioning. A remedy for this is to remove the valve cover(s) and adjust the OH valves per the manufacturers specifications. This enables much easier starting, produces less wear and tear on the starter and may allow your new battery to completely turn that engine over. Out of adjustment valves mimic a weak or failing battery quite well and the engine hangs up on the compression stroke because the compression release system is not working properly. Adjust those darn valves.

SOURCE: my toro mower won't start.

The Toros have a Tecumseh engine and are famous for this. I'd suggest you do a thorough cleaning of the carburetor, but there is a little known secret that I've learned about this particular carb. Pull the bolt from the bottom of the float bowl on the carb (1/2 inch wrench; the "main jet"). Be sure that all the little holes in that jet are clean and you can stick a wire thru them. There is a microscopic hole at the very top of the threads on that brass bolt that often gets clogged and your mower will not start. I use the wire from the needle valve inside the carburetor to stick thru it, as it's about the only thing that'll fit. (note: if you have 50 year old eyes like me, you can't even see this hole w/out specs). Hope this helps and best of luck to you. (also, be sure you put the float bowl back on the right way; there's a bevel in the back that needs to go toward the hinge in the float or the float won't work. Learned that one the hard way as well. )
James