I tackled the job of replacing the leaky oil filter housing gasket on Emily’s e36 318ti this weekend, and as was expected, ran into a few snags along the way. It’s a fairly involved job, but not terribly difficult, with a couple of exceptions. Removing & replacing the stupid serpentine belt was one struggle that shouldn’t have been — that tensioner is a pain in the rear — but the thing that really caused me some consternation was the old gasket. It just didn’t want to come off.
The gasket is the green stuff on the mating surface shown above. The car and its engine have about 220,000 miles on them, and from the looks of things down there, I’m guessing that gasket was installed at the factory. And judging by the grunge on the lower side of the engine and everything underneath, that gasket had been leaking for way too long. It was stuck hard. I tried all manner of things to get it loose; the engine block is of course made from aluminum, so scraping with anything made of steel is automatically a bad idea. After a few failed attempts with lesser tools, I did take a stab at it with a wood chisel and a razor blade, but set them aside after seeing a few small gouges in the metal.
Abrasives are likewise a bad idea because any time you use an abrasive, some of the abrasive is lost from the surface, and with this particular spot it wouldn’t take much to get some of that abrasive inside the oil passages. Really bad idea there.
I had some plastic razor blades that fit into a scraper handle, but the plastic they were made from was a little on the soft side, and proved to be pretty useless. So I started scrounging around the garage & workshop for something made of harder plastic that could be used for the job, and found it; a plastic two-gang blank cover plate.
I’m not sure what kind of plastic it’s made of, but it’s plenty hard. The edge that worked best wasn’t sharp at all, it was more of a 90 degree angle from the back to the top edge with little to no radius to it. I just held the back against the mating surface and pushed against the gasket material, and it literally popped off in chunks. With the other tools I had been trying to get something sharp between the aluminum and the gasket, but that was futile; with the cover plate I had the rest of it completely gone in a matter of a couple of minutes.
I was so impressed with the job it did that I renamed it and gave it special spot in my toolbox. It may be a while before I’m removing another paper gasket, but it’ll be there when I need it!