I pulled my pcv valve today and put a vent in its place. I then plugged the vacuum port on the base of the carb. I drove it over 100 miles the oil did not move on the dip stick when I checked it after the trip. Will it hurt the engine to not run a pcv? Or if I use a smaller vacuum hose for the pcv will it keep it from sucking oil? Before on a trip of about 80 miles the oil would be 1/4 down on the dip stick every time.
Yes, you can use your current hose and plug it with any number of materials after you drill a small hole in that plug, say a 1/8"s or so to limit vacuum. Interesting too is why your engine started using oil after some years, I presume. Often, a valve cover change is at fault where their is zero or inadequate shielding on the head side fo the cover, where oil splash is directly sucked up into the valve. Some sheet metal shielding, like that on OEM Ford covers, is present for that very reason.
In some other posts today, some have had issues and don't like to run a PCV valve. I agree for all-out, competition engines. But, for lesser mortals that only occasionally run up the rpms a lot, that valve does have benefits.
Keep in mind billions of miles (no kidding) have been run by all the makes of cars here in the USA and abroad since PCV valves started up in the early 1960's without any problems. In fact, most of the troubles, even as noted in another post here, relate to possible detonation issues in modified engines and/or unusual oil consumption. Detonation due to oiled combustion chambers is a real issue IF the PCV valve malfunctions or, as noted, changes to the valve covers or other breather related issues, Then yes by all means "hot" engines should not run the valve.
But and IMO, the vast majority of basically street engines we actually "drive" here can likely benefit by running one. The choice is yours.
I am a PCV valve fan too, like any other component, it can be done wrong or right, but when done right, it's evacuating your crankcase at idle and part throttle, nothing wrong with that on the street.
The challenge becomes evacuation at WOT and oil control, but with a well baffled system, oil control is less of an issue. It doesn't help WOT though, and if run there for a long time, the only real answer is also tying it to the air cleaner with some sort of oil control again, but that's never perfect either when feeding right into the carb.
I wonder how a pan evac could work with a PCV. You get part throttle and WOT?
I do agree most vents work well, but, they don't evacuate, they just relieve, and that mist isn't just oil, it's also stuff you want out of there. Does it matter that much? I don't know, probably not, but I use PCVs where I can on the street
