Oil Catch Can project

[davintosh]

I've been doing some more thinking (uh-oh...) on this problem, and it seems to me the biggest problem is when the valve freezes and causes oil from the dipstick tube to get sucked into the intake. In reading through the records on my X5, that's happened twice in its history; a mess I really, really, really don't want to have to deal with.

There are other symptoms that point to a problem with the CCV system, but IMO the oil-to-the-intake failure mode is the worst that can happen; getting the system to work as it's designed while avoiding the worst-case scenario is probably the ultimate solution. That would keep the vehicle from being disabled and allow some time to diagnose and deal with the problem.

So, if I'm going to modify the system to avoid this scenario, might the best solution be something to keep the oil from being drawn up from the dipstick tube? Maybe route the drain hose to another location that isn't submerged in the oil sump... Or put a check valve in it to keep the oil from flowing upstream... Or put a catch can between the CCV and the dipstick tube with a vacuum-operated valve that only allows oil to flow back to the crankcase when the engine is off.

Personally, I like that last option best. Any others I'm missing?