Did I put my catch can on right?
11-21-2006, 10:24 AM
#1
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Did I put my catch can on right?
Since not many people put catch cans on LT1's I wanted to make sure I put it on right. I ran the line from the pass side valve cover to the catch can, then the line from the catch can to the throttle body.
12-11-2006, 07:33 PM
#5
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Stock PCV sucks in a ****load of oil into the intake.
12-12-2006, 07:02 AM
#9
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I don't see where this would do anything.....
I also run an evac system going to the collectors and my pcv is looped to direct manifold vac.
I just don't see where a catch can would do anything...I just don't understand
I also run an evac system going to the collectors and my pcv is looped to direct manifold vac.
I just don't see where a catch can would do anything...I just don't understand
12-12-2006, 09:24 AM
#10
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I too have a HF oil/air separator between the crankcase and the PCV valve. The vapors that it sucks out of the engine are laden with oil vapors, even in a good engine. Mine separates out about a tablespoon of oil per 100-200 mi. which would otherwise be sucked into the intake manifold and along with the fuel. I can't help but think that the CATs will last longer that way and it keeps the inside of the intake manifold from getting covered with oil.
12-12-2006, 11:12 AM
#11
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Yes, in an engine with excessive blowby you can get reverse flow from the valve cover to the throttle body, and the way you hooked up the system will work. Is that the problem you are trying to solve?
12-12-2006, 04:31 PM
#12
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But you didn't put the catch can in the line for the PCV valve. You put it in the vent line that suppies clean, MAF-measured air to the passenger side valve cover, so the vacuum frmo the PCV valve, on the driver's side of the intake can pull the air through the crankcase to remove the harmful vapors.
Yes, in an engine with excessive blowby you can get reverse flow from the valve cover to the throttle body, and the way you hooked up the system will work. Is that the problem you are trying to solve?
Yes, in an engine with excessive blowby you can get reverse flow from the valve cover to the throttle body, and the way you hooked up the system will work. Is that the problem you are trying to solve?
So it pulls air from the bottom of the manifold under the tb to the pcv valve to the tb then to the valve cover? Grr I shoulda known better.
12-12-2006, 05:18 PM
#14
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At that point, it is pulled by vacuum, through the head oil drainback passages, to the crankcase, up through the lifter valley, into slots in the sheet metal cover on the bottom of the intake, through a hole in the bottom of the intake, through a passage in the side of the intake manifold to the PCV valve. The end of the PCV valve that sticks out the side of the manifold has a vacuum applied to it. In the 93/94 engines, that vacuum is provided by a U-shaped tube that bends backwards, and into a vacuum port on the side of the intake manifold. On the 95-97 engines, the vacuum port is on the front of the intake manifold, under the throttle body.
It is not unusual for the flow to be reversed in the line from the passenger valve cover to the throttle body. It can happen at WOT when the rings are subject to maximum blowby, and there is basically no intake manifold vacuum. In that event, there is a baffle in the valve cover that is supposed to keep the oil flipping off the rockers from being entrained in the air leavnig the valve cover. But is isn't very effective.
You may find oil in the rubber hose, and a puddle in the top of the throttle body under the plastic cover. The blades and the intake get coated with oil, which cokes up.
Some people replace the plastic elbow that pokes into the valve cover with a small filter made by Deutsch. That is usually enough to minimize "normal" oil carryover. It gets to be a bigger problem when you have excessive blowby. People with blower motors have to reconnect the system differently, because of the issue of manifold boost.
Your system will "work" with regard to keeping oil out of the throttle body. To accomplish the same thing for the vacuum flow from the PCV valve, you would have to put an oil spearator in the vacuum line from the PCV valve to the intake manifold vacuum connection.
