Have been using a PCV system on my late daily 235 now for 3 years, but begin to think of going back to the road draft tube system.
There just isn't enough manifold vacuum when driving on the freeway and climbing up the hills and mountains at 2500-3000 rpm.
At those rpm the throttle plates are pretty open and the manifold vacuum is very low - too low to suck out all the increased gasses and vapors from the crankcase at higher rpm.
When traveling for a couple of hours the oil vapors like to weep out at the dip stick tube, the distributor mount and the pcv tube mount on the valve cover.
This leaves more of a mess than the road draft tube dumping closer to the ground.
Another thought about going back to the road draft tube is that I don't want to introduce any crankcase vapors into the intake any more - it does create quiet a build up inside the combustion chamber already after 2 years of daily driving - hard to believe until you find yourself scraping off the oil crystals build up. Never seen this after over a decade of road draft use before the PCV system.
Maybe the PCV system was introduced back in the 60s, as many have said before, mostly for political reasons.
It just seems too ineffective and makes more of a mess inside and out the engine than the old road draft system.
So my questions to the daily and frequent drivers out there - what are your experiences and what system do you prefer?
