VAUXHALL Astra - Oil in the Astra's Cooling System
Fearing the worst, the owner of this 2000 Vauxhall Astra 1.7 DTi called us asking if we could look at his car as soon as possible. The owner was meticulous in checking the underbonnet levels every weekend. But the last check revealed thick black oil in the cooling system's header tank. The car was driving perfectly, and there were no signs of overheating. Though, of course, the oil would soon start to block the cooling system. Our diagnosis was swiftly made. Having seen a few similar occurrences on different vehicles, we deduced that the engine's oil cooler had failed, allowing the high pressure oil to push its way into the much lower pressure of the cooling system. Bolted on the side of the oil filter housing with four torx screws, the unit was soon replaced, ensuring the two new sealing rings were properly in place. All that was left now was to clean out the oil from the cooling system!