FYI

I have received several of types of fire in the last couple of months. My opinions are as follows:


Ford trucks equipped with diesel engines are experiencing fires when the block heaters are plugged in and energized. The male plug ends of these block heaters have a tendency to become corroded, especially in northern climates where road salt and calcium chloride was used for deicing roadways. The salt and calcium chloride are corrosive and can attack the copper male spaces of the block heater cord end.

When a circuit has a poor connection between the male spades of the block heater cord and that of a female plug end of an extension cord, increased resistance can create heating at the interface of the connection. If combustible materials are close enough to the hot spot, they can be ignited.

Numerous posts have been made on various Ford diesel truck forums about this condition occurring. Most of what has been written talks about poor connections being made between extension cords that were plugged into household circuits and then plugged into the block heaters. The prevailing consensus focuses on high resistance heating at the connection point.

Ford Motor Company recommends the following maintenance:

To reduce the likeliness of this type of failure, inspect your block heater cord thoroughly especially at the plug end at the front bumper annually. Packing the plugs and lightly coating the electrical terminals at both ends of the cord with Motorcraft Silicone Brake Caliper Grease and Dielectric Compound (Part Number XG-3-A)or equivalent will help prevent water, salt and dirt from leeching into the wiring where corrosion can occur.