Power Stroke question

My boss has two 97 F-350 4X4's. Both trucks have about 96,000 miles and are well maintained but have spent most of their lives idling and pushing snow. They both run good but are slow to start and are blowing white smoke when they start and smell really rich. What should we be looking for? Winter's here and I need to have these things ready to plow.

if the smoke clears up after warm, check the glow plug relay and the glow plugs......use a multimeter instead of a test light, the glow plug replay should have less than a .5 volt drop across the two big terminals when activated, the glow plugs can be checked by removing the connectors at the valve covers, ohm between the glow plug pin and batt ground (the outer 2 pins on the 5 pin connector), should be less than 2 ohms on a cold engine. If any of the pins are dark or the plastic burnt or melted, you need to address the connector and or the vc gasket, as well as the connectors under the valve covers.

Yes, the smoke clears after it's warm. Thanks John, I'll check it out.