A forklift should be checked well and given a test run prior to buying it. This applies particularly to trucks being purchased on the Internet. It is important to find possible issues with trucks acquired from businesses on-line.
Starting the engine from cold is a good idea. Note whether there is too much smoke and the ease with which the engine turns over. This is especially vital with trucks which have IC engines.
The test run should include a check of the truck's performance in challenging situations. A skilled operator can maneuver the truck in reverse and forward, up the ramp.
You can check an IC engine truck yourself. On a clear part of floor, run the truck around for several minutes while a qualified operator tests the hydraulic functions. After that, examine the ground underneath for indications of fluid leakage. Even seemingly insignificant leaking could indicate serious problems that will be really pricey to fix later on.
The masts and chains must be checked by a skilled person. Check with and without a load that the mast works well. Watch for 'binding' or sticking of the mast. A warning sign is play in the mast channels or between the mast and fork carriage. Another is creeping down or creeping forward of the mast when loaded. These could be symptoms of problems with valve, seals or ram.
If the truck is used, the mast may have been changed at some time. Make certain that the mast and any fitted attachments follow the rating plate on a truck. Make certain that the sideshift is not sticking when loaded.
When checking the forks, look closely at the heel thickness for wear or damage. The truck's manufacturer specifies minimum thickness. A loose fit can mean the carriage or hanger points are worn. Look for cracks on the arms at heels and mountings.