Catch Can/Oil Separator
by Pat Goss
Wow, there’s a lot of chatter out there about a new form of deposits that can form in the intake manifolds of cars. It seems that a lot of technicians are calling these GDI deposits. Well, GDI is gasoline direct injection, and they’re blaming it on the direct injection. But, I think it’s something different. I think that it has to do with low tension, or low friction piston rings that are used on virtually all cars these days. Because the piston rings don’t expand and push against the cylinder walls as hard as older ones did, they are more susceptible to deposits forming that cause them to stick. And when the piston rings stick, you get more pressure inside the crankcase, and that forces oil deposits back through the crankcase ventilation system into the intake manifold.
Well, no matter what theory you believe, the fact of the matter is, the deposits are caused by oil getting into the intake. And the harder you drive your car, well, the worse those deposits are going to be. Now I did something on this car that should do away with those problems all together. You see, normally the crankcase ventilation system goes from a port back there, here through the intake, right in behind the throttle body, and that’s where the crankcase fumes go. So what I did, I used what’s called a catch can; it’s actually an oil separator. And inserted that into the middle of the crankcase breather system. So this line goes back into the port, from the crankcase, and it comes up here, goes through this oil separator, this catch can, and then out and into the intake manifold. And what this does, this separates any oil out of those fumes, so the oil stays in the catch can instead of going back into the intake manifold. Now if you drive very gently, chances are you’d never get any benefit out of this. But if you drive your car hard, this could save a ton of money, over the life of the car. Something you might want to consider.
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