Troubleshooting A Diesel Engine's Block Heater

15 May 2019
 Categories: , Blog


Severe cold temperatures are like kryptonite to your diesel engine. A frigid diesel engine won't get spark to start. That is why engine block heaters are so important for your diesel vehicle. However, those block heaters aren't without their share of potential problems. Understanding the potential issues will help you spot signs that you need to seek repairs. Here are some of the things that you will need to watch for with your diesel engine's block heater.

Element Failure

If your engine block heater is not engaging and producing heat, it may be that the element itself has burned out or failed. This is often the result of leaving the block heater plugged in while you start the engine. It is essential that you unplug the block heater before you start the engine, and allow it a minute or so after unplugging before you turn the key and try to start that engine.

Calcium Residue And Build-Up

Residue on the heater element can cause that element to burn out prematurely, leaving you with a previously functional heater that's no longer warming up. That residue is often the direct result of an improper mixture of antifeeze and water. You need to have a little over half the mixture made from antifreeze, but then use distilled water for the rest. If you use any other type of water, the mineral content will cause this residue over time.

Overheating In The Block Heater

If your block heater element is overheating, that is often due to direct contact between the heater itself and the engine wall. When the block heater is installed, it should be checked for distance between the cavity wall. You'll need to remove the o-ring from the heater element first, then put the heater in place. Reach down and check for any contact between the element and the engine wall. If you can feel any contact, that's likely to interfere with proper operation and cause the heater to overheat and burn out.

Any time you have trouble with your diesel engine's block heater, you need to reach out to a diesel engine repair specialist or a place like South Houston Engine. The mechanic can evaluate the condition of the block heater, the installation, and the mixture of the antifreeze to ensure that none of these things are contributing to the problem. As soon as the source is isolated, it can be repaired to restore your block heater's functionality and keep your engine turning over in those cold weather climates.