Unimog Club UK

That makes more sense. I've only ever studied an upright stack on a U1000 and that was how it was fitted there. I was surprised that it isn't sealed, but it clearly works just as well.

If the vehicle is used in water does this system change? Surely then the water will get in through the open joint and fall into the upright bit that goes into the stack? Probably not when running, but if you stall or shut it down?