Fix Coolant Leaks: 1990 GMC S15 2.5L 4 Cyl. Standard Cab Pickup

Follow the steps in this video to see how to fix minor coolant (antifreeze) leaks in your 1990 GMC S15. Leaking coolant / antifreeze is one of the more common types of leaking fluid from S15 engines. Engine coolant (which is also called antifreeze or anti-freeze) moves through the inside of your S15 engine and keeps it from overheating. Coolant / antifreeze can leak from the reservoir, radiator or any hose, in 1990 S15 with the 2.5 liter engine. However, a coolant leak (aka an antifreeze leak) is most likely to occur where the hoses connect to the engine or radiator. Otherwise, your S15 may have a radiator leak. This video shows you where the coolant reservoir, hoses and connections on your 1990 S15 Base are located and the steps needed to fix minor leaks.

A few things to note about coolant is that it is sweet tasting and highly toxic, so it can end up in the dog's stomach pretty quickly. If you ignore a small coolant leak long enough, you will run out of coolant, which leads to an overheated engine and other serious, but highly avoidable, problems. An anti-freeze leak can cause the temp sensor to record high engine temperatures in a 1990 GMC S15. Always protect yourself with safety glasses and gloves when working with the coolant on your S15.