It seems that no matter how hard we try, every classic English sports car leaks oil. I’ve seen many forum posts over the years where people claim to make a leak-free car, and certainly some of them leak very little, but it just seems inevitable that these old cars will leak, no matter how hard you try. And even if you stop them from leaking, it seems just a matter of time before they start leaking once again.

In this post, I wanted to show you some photos of a particular Bugeye engine that just arrived in our shop. This one is leaking more than usual, and in this case it makes a lot of sense to try to reduce or stop the leaking all together. (We’re always optimistic, but we’re also realistic).

Of note in this case is the head gasket leak. We’ve added ultraviolet dye to this engine, so you see a bright green trace wherever there are leaks (a UV kit makes it easy to see exactly where we have leaks). Take a look at the green trace on the left side of the engine. This is directly in line with the oil galley that feeds the head up through the rocker arm pedestal, and the oil as it travels from the block up to the head sometimes leaks at this location. Unfortunately, once it starts leaking, you have to change the head gasket.

We will remove the head to inspect. it could be a bad head gasket or the head is not flat (or block) or too much combustion pressure with an excessively high compression ratio, for example. Or maybe the oil pressure relief valve is not working or set too high… these are all things we will investigate when we get the engine out of the car.