NotTaR of small Gasoline Engines and Rotary Lawn Mowers : Testing a used lawn mower before you buy
 Copyright © 1994-2007, Samuel M. Goldwasser. All Rights Reserved. Reproduction of this document in whole or in part is permitted if both of the following conditions are satisfied: 1. This notice is included in its entirety at the beginning. 2. There is no charge except to cover the costs of copying. I may be contacted via the Sci.Electronics.Repair FAQ (www.repairfaq.org) Email Links Page.

     << Additional comments on wi.. |  Index  | Discussion of 2 stroke en.. >>

Testing a used lawn mower before you buy

A used mower at a bargain price may not turn out to be such a bargain if you have to do extensive repairs. There are two types: the living and the dead.

If the owner claims the mower will start and is prepared to demonstrate, this is usually a good sign! However, first, take a moment to check the following:

(Disconnect the spark plug wire, and tie it safely away from the spark plug terminal to prevent accidental starting if you are doing anything more than looking.)

If there is gasoline in the fuel tank and it will start without undo effort, then there is an excellent chance that the engine is in good condition.

In most cases, if the engine starts reasonably easily, there will be no really serious problems. The ignition system may require a tune-up or the carburetor may need cleaning and/or adjustment. Even a hard-to-start mower may very likely restored to tip-top shape with this type of intermediate level maintenance. Of course, the blade may have to be sharpened or replaced.

If the engine doesn't work - no gas in the fuel tank and no handy gas can is usually a tip off of this - how can you be fairly sure that there are no major mechanical problems? Note that the objective here is not to identify THE problem but to have a good idea of whether repairs will be really expensive or difficult. Thus, we won't even bother checking the carburetor or spark as problems in these areas are minor compared to those caused by internal mechanical damage. Here are some simple tests you can do without tools and without overly upsetting the people running the sale or junk yard:

WARNING: disconnect the spark plug wire and tie it safely away from the spark plug terminal if you will be doing anything under the deck. Yes, I know, there is nothing in the fuel tank but it doesn't hurt to be safe. Use a rag or proper work gloves if you attempt to rotate the blade directly.

Assuming the engine doesn't flunk any of these tests, then you may end up with a functioning mower with relatively little additional cost and effort.

 <<Additional comments on wi.. | ToC | Discussion of 2 stroke en..>>