Do you really need a PCV on your engine? If it is not working, will you blow your engine and how did we ever get along without them?
PCV?
- Thread starter CourierDriver
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Before PCV the engines just had a breather filter. Its due to blow-by; if it wasnt there, as in the engine was completely sealed, the seals would blow out from the pressure devloped.
PCV is better for the environment and the engine. As you can imagine the blow-by is exhaust and various other noxious substances. With a breather, it would just exit the engine into the atmosphere. A PCV not only sucks the fumes into the engine to be burned, but it also forces fresh air through the engine, keeping the internal environment cleaner. The way it does this is a connection is made to the air intake tube, before the throttle body, which as no vacuum. Then another connection is made through a PCV valve to the intake manifold behind the throttle body, where there is plenty of vacuum.
PCV is better for the environment and the engine. As you can imagine the blow-by is exhaust and various other noxious substances. With a breather, it would just exit the engine into the atmosphere. A PCV not only sucks the fumes into the engine to be burned, but it also forces fresh air through the engine, keeping the internal environment cleaner. The way it does this is a connection is made to the air intake tube, before the throttle body, which as no vacuum. Then another connection is made through a PCV valve to the intake manifold behind the throttle body, where there is plenty of vacuum.
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Colts got it covered - you want that PCV system functional.
Previous to a breather, some "progressive" manufacturers had a down tube coming out of the crankcase. It worked when the car was moving. I guess the theory was to vent the back pressure.
Long before my time, though. Some historians may chime in on this one.
Long before my time, though. Some historians may chime in on this one.
Originally Posted By: ChiTDI
Previous to a breather, some "progressive" manufacturers had a down tube coming out of the crankcase. It worked when the car was moving. I guess the theory was to vent the back pressure.
Long before my time, though. Some historians may chime in on this one.
Yup. The sharp engineers had a PCV system that used a tube out of the crankcase that ran to a low pressure area of the vehicle (low pressure area when the vehicle was in motion). When the vehicle was in motion, vapors would be pulled out of the crank case and vented/pulled into the atmosphere.
Nascar techs do the same thing with their exhaust outlets, looking for the low pressure area to put the tailpipes to increase flow.
Previous to a breather, some "progressive" manufacturers had a down tube coming out of the crankcase. It worked when the car was moving. I guess the theory was to vent the back pressure.
Long before my time, though. Some historians may chime in on this one.
Yup. The sharp engineers had a PCV system that used a tube out of the crankcase that ran to a low pressure area of the vehicle (low pressure area when the vehicle was in motion). When the vehicle was in motion, vapors would be pulled out of the crank case and vented/pulled into the atmosphere.
Nascar techs do the same thing with their exhaust outlets, looking for the low pressure area to put the tailpipes to increase flow.
Do you need it? No.
Will your engine blow? No.
Now as said before, Engine was designed to run with PCV. Very simple piece, very little maintenance. Keep clean and keep it on the engine.
Will your engine blow? No.
Now as said before, Engine was designed to run with PCV. Very simple piece, very little maintenance. Keep clean and keep it on the engine.
thanks to all
Originally Posted By: ChiTDI
Previous to a breather, some "progressive" manufacturers had a down tube coming out of the crankcase. It worked when the car was moving. I guess the theory was to vent the back pressure.
Long before my time, though. Some historians may chime in on this one.
Road draft tube. Would let the fumes out of the engine, and could deposit "crud" onto the middle of the roadway. I recall being told that the worst time to drive on a road was just after it started raining: the rain hadn't had enough time to wash away the oil buildup on it. I'm guessing most of that was from road draft tubes (and whatever else was being dripped from leaks); not sure if they still teach that in driver's ed or not today.
Previous to a breather, some "progressive" manufacturers had a down tube coming out of the crankcase. It worked when the car was moving. I guess the theory was to vent the back pressure.
Long before my time, though. Some historians may chime in on this one.
Road draft tube. Would let the fumes out of the engine, and could deposit "crud" onto the middle of the roadway. I recall being told that the worst time to drive on a road was just after it started raining: the rain hadn't had enough time to wash away the oil buildup on it. I'm guessing most of that was from road draft tubes (and whatever else was being dripped from leaks); not sure if they still teach that in driver's ed or not today.
Heavy trucks kept the road tube for much longer than passenger cars.
Originally Posted By: supton
I recall being told that the worst time to drive on a road was just after it started raining: the rain hadn't had enough time to wash away the oil buildup on it. I'm guessing most of that was from road draft tubes (and whatever else was being dripped from leaks); not sure if they still teach that in driver's ed or not today.
Yes, they do teach that is driver's ed. That is also a current question for CDL tests and truck driver schools. The instructors call it a "chemical banana peel".
I read somewhere, many years ago, that the first vehicle to have a PCV valve was a GMC pickup. I no longer can remember the first year they put it on, however.
I recall being told that the worst time to drive on a road was just after it started raining: the rain hadn't had enough time to wash away the oil buildup on it. I'm guessing most of that was from road draft tubes (and whatever else was being dripped from leaks); not sure if they still teach that in driver's ed or not today.
Yes, they do teach that is driver's ed. That is also a current question for CDL tests and truck driver schools. The instructors call it a "chemical banana peel".
I read somewhere, many years ago, that the first vehicle to have a PCV valve was a GMC pickup. I no longer can remember the first year they put it on, however.
Originally Posted By: Colt45ws
Before PCV the engines just had a breather filter. Its due to blow-by; if it wasnt there, as in the engine was completely sealed, the seals would blow out from the pressure devloped.
PCV is better for the environment and the engine. As you can imagine the blow-by is exhaust and various other noxious substances. With a breather, it would just exit the engine into the atmosphere. A PCV not only sucks the fumes into the engine to be burned, but it also forces fresh air through the engine, keeping the internal environment cleaner. The way it does this is a connection is made to the air intake tube, before the throttle body, which as no vacuum. Then another connection is made through a PCV valve to the intake manifold behind the throttle body, where there is plenty of vacuum.
Cars had road draft tubes. A pipe that simply blew out excess gasses, vapors, and oil to the ground. A dark oil strip was in the middle of roads from this.
And nowadays, the inlet has no need to be in the intake pipe. It is actually a poor method, although some do it.
Before PCV the engines just had a breather filter. Its due to blow-by; if it wasnt there, as in the engine was completely sealed, the seals would blow out from the pressure devloped.
PCV is better for the environment and the engine. As you can imagine the blow-by is exhaust and various other noxious substances. With a breather, it would just exit the engine into the atmosphere. A PCV not only sucks the fumes into the engine to be burned, but it also forces fresh air through the engine, keeping the internal environment cleaner. The way it does this is a connection is made to the air intake tube, before the throttle body, which as no vacuum. Then another connection is made through a PCV valve to the intake manifold behind the throttle body, where there is plenty of vacuum.
Cars had road draft tubes. A pipe that simply blew out excess gasses, vapors, and oil to the ground. A dark oil strip was in the middle of roads from this.
And nowadays, the inlet has no need to be in the intake pipe. It is actually a poor method, although some do it.
i remember when they first came out with them. about 1962-1964.. my dad said it will make the engine last a LOT longer. cause the air going into the crankcase will be better filtered. and it keeps moisture out of the crankcase by feeding it to the intake. dont for get all acids are water base. think about it.
Yes, you need a PCV system. When I was young, I had a 1971 Plymouth Duster. It was equipped with a PCV system. As an experiment and to see if the performance would improve, I replaced the PCV valve with a homemade road draft tube. After a relatively short time, I found a build-up of yellow gunk under the oil fill cap. The homemade road draft tube was nowhere as effective as the PCV system at scavenging combustion by-products from the crankcase. I replaced the PCV system promptly. And there's some firsthand experience for you.
I have a homemade PCV system in my Bug and even that is a tremendous improvement over the simple breather I had before. It sucks an unbelievable amount of steam and other vapors out of the oil, much more than got out via the vent. I can't believe I ever did without it.
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