Craftsman MowerDear Ole Mechanic;

I have a new riding mower that I bought last fall and now it won’t start.  It is a CraftsmanŽ with a 16 horsepower IC engine and a forty-inch cut.  What could be wrong with a mower this new?

Won’t Go, Won't Mow


Dear Won’t;

I have confirmed that your mower is the one that has sat uncovered and out in the front yard all winter near one of the locl churches.  Since I pass by it a couple of times a week or so, I know how long it has been sitting out there and can probably guess at what is wrong.  First, the battery is probably discharged because the dust on top of the battery has gotten damp from the rains we have had during this past winter.  The damp dust has allowed a little electricity to pass across the top of the battery and has slowly allowed the battery to go completely dead.  Allowing the battery to slowly discharge all the way may have ruined it.  About the only thing you can try is to have the battery charged and tested.  That may save it; if not, then you will need to get a new battery.

Also, the mower has been sitting long enough that the gas has gone bad--unless you treated it with a gas stabilizer for storage or ran it completely out of gas last fall.  If there was non-treated gas left in it, then you will need to drain all the old gas out of the tank and carburetor.  Since it has sat out in several rain showers,  there may be some water in the gas, so even if it was treated you may need to drain the old gas out.  Hopefully, putting fresh gas in it after all the old stuff is out will dissolve the gum and varnish that has formed in the carburetor.  If it doesn't, then the carburetor will need to be taken apart and cleaned.

Sitting out in the weather may have corroded some of the start/run safety-interlock switches.  If they have corroded internally, then they may not allow electricity to pass and will keep the starter from working or, if the starter does work, it may cut off the ignition so that the engine will not start.  If that happens, then one or more of the safety switches may need to be replaced. 

Sitting out in the weather has probably caused the blades to rust, so they will need to be resharpened.

Your big problem is that most lawn mowers are made to be used in fair weather.  They are not intended to be used in the rain, so they are not designed to be stored outside in the weather and cannot endure even our mild winter weather like a car or truck can.

How could all of these problems been prevented?  A lot of it could have been prevented by running the engine out of gas or by adding a couple of ounces of gas storage treatment, wiping the dust off of the battery and storing it inside a shed, or at least throwing a tarp over it for the winter and anytime rain is expected.  Since you didn’t do any of these things, be prepared to spend at least $100 and maybe more to get the mower running.  Next fall, I suggest that you go to the local library, dig out old issues of The Harper News and read my old column on winterizing a mower.

Herr Professor Nuzanbolts