I just realized that my 360 engine in my challenger doesn't have a PCV valve hooked up. There are aftermarket valve covers that have vent breather on either side.
The top of both valve covers are damp with oil coming out of the breathers. do i need a pcv valve, and if so how do i hook it up.
Posted By: Andrewh
Re: Effects of no PCV valve - 07/12/10 04:52 PM
pcv is really emmisions. Vents are fine, but you will get that oil film.
You should have a splash shield or filter element on the breather to catch the oil.
Posted By: 68HemiB
Re: Effects of no PCV valve - 07/12/10 04:55 PM
Positive Crankcase Ventilation is not simply a "smog device", it is a good thing for total engine health. Removing blow-by, condensation, and the like with a PCV system will result in a much healthier engine than any passive breather or road-draft tube will accomplish.
A proper "type IV" system will include two lines connecting to the crankcase. One will be to manifold vacuum, and will contain the PCV valve proper. The other will be the fresh air supply. Ideally, it will pull from inside the area contained by the air filter (to provide a filtered fresh air source), and will have a small dedicated screen-type filter.
During normal operation, a small amount of crankcase air (and any excess pressure) will be drawn through the PCV valve into the intake manifold to be burned in the engine. The air will be replaced by the fresh air side. During unusual periods of low vacuum and/or excessive blow-by, the fresh air line can handle the excess load, and flow "backwards" into the carb to be burned by the engine.
Posted By: Stanton
Re: Effects of no PCV valve - 07/12/10 04:58 PM
PCV is "positive" crankcase ventilation. The whole point was to ensure the fumes (moisture) was being drawn out of the crankcase. Had nothing to do with emissions what-so-ever. PCV valves were around long before emissions regs.
Posted By: 5spdcuda
Re: Effects of no PCV valve - 07/12/10 05:05 PM
Yes, a PCV should be used. It fits into a rubber grommet on either of the valve covers. A rubber hose connects it to a large tube at the base of the carb. Without positive crankcase ventilation the engine will have condensation and excess contaminates in the oil. It also keeps the outside of the engine cleaner. You do need a breather on the opposite side valve cover. It does NOT hinder performance.
Posted By: Andrewh
Re: Effects of no PCV valve - 07/12/10 05:13 PM
my mistake. Seen a lot of cars with aftermarket valve covers that don't run them though.
Posted By: buildanother
Re: Effects of no PCV valve - 07/12/10 06:08 PM
just don't make the no breather mistake, adding the pcv valve to substitute for any breather. That don't work.
Posted By: az426john
Re: Effects of no PCV valve - 07/12/10 06:37 PM
Before PCV was introduced most cars and trucks had road draft tubes with filters that were cleaned on a perodic basis for crankcase ventilation.
Posted By: therocks
Re: Effects of no PCV valve - 07/12/10 07:31 PM
GTX is correct.It was one of the first attempts at emissions.Ive run 2 breatgers on my 440 for probally 20 years.My kid does the same on his never been apart 413 in his 62 300.The 360 in his truck is the same even though its been run little since rebuild.None have any problems.His 413 sees probally 6000 miles a years street and strip.My built 440 has an M1 and Dominator and neither have vacuum provisions and Im not drilling any when I have no problems.Rocky
Posted By: RapidRobert
Re: Effects of no PCV valve - 01/25/11 04:15 AM
As said the PCV replaced the road draft tube in about the '62 or 3 model year. need PCV in either valve cover plumbed to to either the intake (if single plane & if carb has no PCV nipple) or carb base and the other valve cover needs a filtered opening for fresh air to be drawn in (or a closed breather to the air cleaner to replenish the air from there) to replace the fumes that are sucked out. If an evac system in the headers will pull enough fumes out I'd rather not have the controlled vac leak of a PCV but it does add to the worlds pollution & that's assuming a header evac system pulls enough vac
Posted By: stumpy
Re: Effects of no PCV valve - 01/25/11 07:11 PM
There is such a small ammount of oil fumes you will never notice it. There will be no loss of power or any other affects to running a pcv except you won't have the oil slick on the valve covers.
Posted By: MLR426
Re: Effects of no PCV valve - 01/25/11 08:51 PM
Depends on the condition of the engine it could build extreme postitive crank case pressure and start leaking everywhere trying to push oil out.
logan426
Posted By: west
Re: Effects of no PCV valve - 01/25/11 10:12 PM
keeping the oil off the road from the draft tube is a type of emission control in itself.
