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Why is positive crankcase ventilation incorporated into petrol engines?
Raymondrampape
As the name suggests, there is "positive" pressure in your crankase from all that movement.
you could create a vent that just let it out into the atmosphere, but since it has fumes from oil/gas it's bad for the environment. this is why it is piped back into your intake system and burned off in the engine.
-R. Mesyef
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∙ 15y ago
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Is there a PCV valve on a 1999 Toyota solara?
Yes, both the 6 cylinder and 4 cylinder engines have PCV (Positive Crankcase Ventilation) valves.
Does a 1991 Pontiac Grand Am 2.5 manual trans have a PCV valve?
yes it does, all engines have a pcv valve ( positive crankcase ventilation ) valve. it is on the engine and vacuum goes to it from the valve covers.
How does positive crank ventilation work?
The question should really be "How does positive crankcase ventilation work?" You can't ventilate a crank, it's either solid (roller bearing crank) or the only spaces are oilways. Positive crankcase ventilation, PCV, is used to prevent a build-up of combustion gases in the crankcase. The piston rings prevent most combustion gases getting down the sides of the pistons and into the crankcase but a little does sneak past. This is called 'blow by' and increases as the engine wears. If there was no ventilation, pressure would build in the crankcase and cause oil leaks and other trouble. In early engines the crankcase was just vented to atmoshere via an oil trap so combustion gas fumes and some oil vapour escaped into the air. Later, to prevent this, the crankcase was vented instead to a low pressure part of the inlet system. The engine then consumes its own fumes. Originally this was just a flow restricting hole to the inle manifold but complication has crept in over the years. We have seen one-way valves, 'gulp valves' and similar all intended to hold the crankcase pressure just below atmospheric and get the engine to consume it own fumes without upsetting fuelling accuracy. On diesel engines and supercharged engines a pressure lower than atmospheric can be created by putting a venturi in the the inlet. On a conventional gasoline engine the inlet is always below atmospheric pressure. Mark www.top-biker.com
What does a PCV valve contro in ford trucks?
PCV stands for positive crankcase ventilation. It prevents an over pressure condition in your engines crankcase that could cause oil to be forced past the pistin rings into the firing chamnber. If your PCV is clogged you will probably see increased oil useage and on some vehicles gas mileage may be affected as well. On cars prior to PCV there was an open tube that vented excess pressure over the side. With PCV the pressure is vented into the intake manifold and used as part of the fuel/air mixture.
What would caouse air to come out of dip stick on 455 olds engine?
Pressure builds up in the crankcase on all internal combustion engines. If your 455 is an older model it should have an overboard vent but you still may have some pressure relieved through the dipstick tube. Newer engines use a PCV or positive crankcase ventilation valve to relieve the pressure. You probably won't have any vented through the dipstick tube if that valve is working properly. They are pretty cheap (3 to 4 dollars) and easy to change. If your pcv is clogged it may also cause your engine to use more oil than it normally would.
When should you turn on power ventilation system?
Turn on the ventilation system before you start the engine; normally on inboard engines which are in a confined space.
Where is the crankcase on a 2000 Ford Explorer?
The crankcase on ALL engines is at the bottom of the engine, covering the crankshaft (that's where the name Crank-Case comes from) and holds the oil in the engine.
Theoretical of blow-by in engine?
Some blowby is normal in all engines, this is the reason for the pcv system (positive crankcase ventilation). excessive blow by, is the cause of worn pistons and or piston rings. excessive blowby will alot of times show up in the air cleaner box as raw oil that the pcv system just could not handle. If indeed you do have excessive blowby it is a major internal engine failure. Again blowby is normal in all engines, but it should never be so excessive as to show smoke in the blow by
If a new intake gasket was installed in a 98 Buick Lesabre 3800 v6 and if you pull the oil dipstick with the car running there is a suction into the crankcase that can be heard and felt by placing a finger over the hole is it a vaccum hose?
This is not unusual. The Positive Crankcase Ventilation (PCV) system uses engine vacuum to create a negative pressure situation within the engine for emmissions purposes. All internal combustion engines have leakage past the piston rings, regardless of age. The PCV draws the unburned hydrocarbons that have leaked past the rings into the intake to be burned in the combusion chambers. This also has the added benefit of helping keep the engine oil cleaner by reducing the amount of contamination in the crankcase.
How does a PCV valve work on a 1987 jeep wrangler?
PCV stands for positive crankcase ventilation. You crankcase needs to be ventilated to keep pressure down. Too much pressure will cause excessive oil consumption by forcing oil past the rings into the firing chamber thus burning oil. In the old days the crankcase was vented to the atmosphere causing polution. On todays engines it is a simple ball valve that opens when the engine is running. The pcv ball is sucked open to allow the excessive pressure to be returned to the intake manifold and it becomes part of the fuel air mixture. If the valve is stuck the crankcase pressure builds up and forces oil past the rings as if no vent were there. Checking the pcv is easy. Just pull it out and shake it. You should hear the ball moving back and forth in there. If you don't you will need to replace it.
Which Crankcase oil for 2 cycle engine?
none 2 cycle engines run a gas/oil mix for lubrication
What causes back pressure?
Usually back pressure is caused by worn piston rings, combustion gasses passing the rings into the sump, there are also some engines which have positive oil pan ventilation trough the air filter with a suction pipe (BMW engines)Back pessure goes hand in hand with light blue smoke and lack of compression.
