Installing an Engine Block Heater

A block heater in a car engine.
What You'll Need
Philips screwdriver
Ratchet and sockets
Torque wrench
Engine coolant
Drain pan
Felt tip pen
Tape measure
Engine block heater
Silicone heat transfer grease
What You'll Need
Philips screwdriver
Ratchet and sockets
Torque wrench
Engine coolant
Drain pan
Felt tip pen
Tape measure
Engine block heater
Silicone heat transfer grease

An engine block heater is designed to reduce stress on your engine during cold weather. The heater warms up the oil or coolant, making it much easier to start a cold engine. Additionally, the typical passenger automobile engine operates most efficiently at approximately 200 degrees Fahrenheit. Using an electric heater allows the engine to reach this temperature much more quickly. It can improve your vehicle's fuel economy by approximately 10 percent in the winter. The heater plugs into a typical 110 volt alternating current outlet. Consider installing an automatic outlet timer because it is only necessary to heat the engine for about two hours before driving.

There are several different types of engine heaters available. The specific one you choose will depend on the make and model of your vehicle as well as your mechanical ability. The simplest kind of engine heater replaces the oil dipstick. A slightly more complicated type of heater splices into the upper radiator hose. It can be installed in a matter of minutes with a screwdriver. The most effective engine block heaters replace a freeze plug on the bottom of the engine block. General installation instructions for this type are listed below.

Step 1 — Jack up the Vehicle

Working on a cold vehicle will protect you from burning yourself, but working on a warm engine makes it slightly easier to remove the drain plugs if they are made of a different metal than the engine block. Choose the option that you are comfortable with. Engine heaters come in different wattages. Select one that meets your needs and is compatible with your vehicle. Jack up the front end of the vehicle and remove the plastic engine cover.

Step 2 — Drain Engine

Refer to your owner's manual for instructions specific to your equipment. Remove the clips holding the radiator cover and the bolts holding the radiator mounting bracket. Slide a pan under the engine and pull out the specified drain plug. This is usually at the rear of the engine block. Remove the radiator cap to accelerate drainage.

Step 3Plug in Heater

Prefit the connection between the heating rod and the power cord in case you have to do it blind later. Drop the male end of the cord into the engine compartment. Lubricate the hole with grease up to, but no further than, the metal clip. Insert the rod into the hole. If trapped air is presenting resistance, displace it. The metal clip should be facing the rear of the vehicle. It will make an audible snap when the heater slides into place. Some types have to be tightened with a wrench to a specified torque.

Step 4Route Power Cord

Plug the cord into the rod. Run the wire harness through the engine compartment and out the front grill. Follow the included directions or improvise. Avoid moving any parts or hoses. Once the cord is in the correct position, secure it with wire ties. Do not leave any slack behind the first tie. You want to keep the cord off the engine manifold.

You now have a vehicle that will be more fuel efficient.