PCV Circuit Modification
Posted: Tue Apr 07, 2009 10:49 am
Hi all you clever people,
I'm busy with a small mod to my PCV system, I have placed a oil collector container inbetween the PCV valve and the intake manifold... on the standard system the PCV valve sucks combustion air and oil vapour trapped in the sump into the intake manifold for reburning, the problem with these systems is that on a high performance engine this oil vapour condenses and coats the intake and eventually leads to a pool of oil lying in the bottom of the intake manifold, there is an easy way to overcome this...
So far I have implemented an oil collector container, placed between the PCV valve and the intake, this oil collector has a filter in it that catches/condenses the oil vapour, where it collects at the bottom of the container, the combustion gases are allowed to continue to the intake for reburning... at present I pour any oil collected back into the engine via the oil filler cap every so often... This mod is common practice on high performance/racing engines... then Allan said... 'Why don't you just return the bit of oil to the engine automatically?'... the basic idea is to let as little oil vapour as possible into the intake, keeping the intake clean and the engine performing tip-top!
Take a look at the diagram below, pretty self explanatory:
To implement an auto oil back to sump thingy, I plan on putting a pipe at the bottom of the oil collector and making an input via the old manual fuel pump opening(presently blanked off). Then I will use a fuel cut off valve of sorts, so that when the engine is running, the oil return to sump is closed off... then the PCV valve can operate as intended... and the blow-by combustion gas can be routed back to the intake manifold for reburning. Then when the ignition is off, the cut off valve opens, allowing any oil in the collector to return to the sump.
A system like this is really easy to implement, I only have one issue to resolve... a standard fuel cut off valve works exactly opposite to what I need, it's open when I want it closed and closed when I want it open... so does one get a cut off valve that works the other way around? The other option is that I use a normal fuel cut off valve and a timer curcuit, so that when the ignition is switched off the cut off valve opens for 5 minutes or so, allowing any oil to return to sump, and then closes again. The circuit would also have to shut the valve off when the ign is turned on, even though the 5 minutes has not passed... Gert any suggestions/help on such a circuit? Anyone know where I can get an elec cut off valve that works the other way around to the normal fuel cut off valves?
Anybody got ideas to help??
Bretton
I'm busy with a small mod to my PCV system, I have placed a oil collector container inbetween the PCV valve and the intake manifold... on the standard system the PCV valve sucks combustion air and oil vapour trapped in the sump into the intake manifold for reburning, the problem with these systems is that on a high performance engine this oil vapour condenses and coats the intake and eventually leads to a pool of oil lying in the bottom of the intake manifold, there is an easy way to overcome this...
So far I have implemented an oil collector container, placed between the PCV valve and the intake, this oil collector has a filter in it that catches/condenses the oil vapour, where it collects at the bottom of the container, the combustion gases are allowed to continue to the intake for reburning... at present I pour any oil collected back into the engine via the oil filler cap every so often... This mod is common practice on high performance/racing engines... then Allan said... 'Why don't you just return the bit of oil to the engine automatically?'... the basic idea is to let as little oil vapour as possible into the intake, keeping the intake clean and the engine performing tip-top!
Take a look at the diagram below, pretty self explanatory:
To implement an auto oil back to sump thingy, I plan on putting a pipe at the bottom of the oil collector and making an input via the old manual fuel pump opening(presently blanked off). Then I will use a fuel cut off valve of sorts, so that when the engine is running, the oil return to sump is closed off... then the PCV valve can operate as intended... and the blow-by combustion gas can be routed back to the intake manifold for reburning. Then when the ignition is off, the cut off valve opens, allowing any oil in the collector to return to the sump.
A system like this is really easy to implement, I only have one issue to resolve... a standard fuel cut off valve works exactly opposite to what I need, it's open when I want it closed and closed when I want it open... so does one get a cut off valve that works the other way around? The other option is that I use a normal fuel cut off valve and a timer curcuit, so that when the ignition is switched off the cut off valve opens for 5 minutes or so, allowing any oil to return to sump, and then closes again. The circuit would also have to shut the valve off when the ign is turned on, even though the 5 minutes has not passed... Gert any suggestions/help on such a circuit? Anyone know where I can get an elec cut off valve that works the other way around to the normal fuel cut off valves?
Anybody got ideas to help??
Bretton