Long-Term Coolant in Oil Use, Surprisingly Good Component Condition
When it comes to the renowned 3800 V6 engine from GM, even a treacherous mixture of oil and coolant cannot demolish it. However, it can definitely create chaos.
The substance in the photo resembles orange juice, however it is actually a combination of orange engine coolant and oil which results in a noxious sludge that typically leads to failure of internal combustion parts. A recent disassembly video by I Do Cars on YouTube delves into the impact of this mixture on a Series III 3800, the ultimate version of GM’s long-lasting 3.8-liter six-cylinder engine which dates back to the 1960s. The engine featured in the video is from a 2006 Pontiac Grand Prix GT with 126,000 miles, and its condition is far from ideal.
It is indisputable that the initial sign of trouble is when orange coolant gushes from the engine’s drain plug instead of oil. Inadequate lubrication can quickly lead to an overheated engine and result in it locking up. However, upon manual rotation, this particular engine shows no signs of difficulty, displaying impressive compression. It isn’t until the lower intake is removed during the disassembly that significant issues begin to surface.
At some stage, the gaskets in the lower intake manifold became faulty, resulting in the leakage of coolant into the oil. Upon closer examination, it was discovered that certain parts of the gaskets had completely disintegrated. Unfortunately, this engine continued to be used even after the gaskets had failed, causing a build-up of a sticky substance in the oil and coolant channels. This eventually caused the gaskets to melt into the engine heads due to the extreme temperatures. What a troublesome situation.
Given the chaotic state of affairs, one would anticipate substantial harm to the cylinders and lower portion. However, surprisingly, there is none. While the lifters are coated in grime and the oil pan presents a revolting milkshake appearance, the cylinder walls, pistons, and crankshaft have endured relatively well. Admittedly, some wear can be spotted in certain areas, yet considering the overall deficiency of lubrication within this particular engine, the time-honored 3800 engine lives up to its celebrated reputation. Remarkably, even the rod bearings appear suitable for reuse.
According to the video, it is possible to reconstruct the engine using most of its original parts even with the presence of orange juice in its oil. We were aware that the previous 3800 model was famously known for its durability. This video provides us with a more comprehensive understanding of the remarkable strength of this engine.
Source: I Do Cars / YouTube