First, keep in mind that a problem with one part of an engine could well show up as a symptom elsewhere. What looks like a governor problem often turns out to be a balky carburetor. Take the diagnostics step by step all the way through, then evaluate whether the engine is worth the trouble to repair it, or whether it makes more sense to buy a repower kit and drop in a new, more powerful motor.
Problem: Engine will not start.
You can usually divide ‘won’t start’ problems into two causes: fuel or ignition.
1) Make sure the fuel is fresh, and the oil/gas mix is right. As basic as that sounds, bad gas is one of the most common causes of engine failure.
2) Make sure that there’s a spark. Remove a spark plug and ground the hex to bare metal on the motor, then spin the engine. You should see a blue spark jump the gap. If the spark is weak, or there is no spark, try the same thing with a new spark plug. If you still get no spark on an older machine, clean and set the points. On a newer machine, the electronic ignition may need to be replaced.
If you’ve got spark but no start, it’s time to check the carburetor.
1. Check fuel valve and lines to be sure that fresh gas is getting to the carburetor. Don’t forget to check the screens to be sure that they’re clear, and that the fuel cap vent is open.
2. Prime the carburetor with a shot of starting fluid and try to start ‘er up. If it runs for a couple of seconds but then quits, it’s a good bet that the carburetor needs to be rebuilt. A carb kit with quality parts is easy to install. Most dealers will carry a wide assortment of Toro parts and other quality brands.
3. It’s possible that there’s an air leak. Check all the mounting screws and bolts to be sure that they’re snug, and that the gaskets are intact.
Problem: Engine start but runs poorly. (Dies, surges, runs only on choke)
All or any of these could be symptoms of a carburetor problem. 90% of the time, a good cleaning will solve the problem. That means disassembling, cleaning and rebuilding – which will go much smoother if you use the engine manual as your guide.
MISC. ENGINE PROBLEMS
When your motor springs an oil leak or spouts smoke, it’s trying to tell you something. The color of the smoke and the location of the leak can point to problems that need fixing – or tell you that it’s time to repower the mower with a new Jacobsen Greens king.
Oil smoke or leak near the carburetor can mean the drain holes in the breather cover need to be cleaned. Don’t forget to replace the gasket with a new one picked up at any store that stocks Cushman, Kohler, or Jacobsen Engines.
Oil smoke through the muffler can mean worn rings or worn valve guides. Either one of those is a hint that it’s time to repower that piece of equipment with a new Kohler engine.
Keep in mind that worn-out engines may have more than one problem. If you’d rather not spend the next several months pulling that same piece of equipment back into the shop for yet another repair, your best option may be a complete repower using a remanufactured or new Cushman engine.
