catch can question
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catch can question
I would like to know if anyone has experienced any type of mechanical(engine) problem that they believe could have been prevented if they had installed a catch can. Also has anyone experienced a problem that they believe was from having a catch can installed. Did any corvettes come factory equipped with a catch can? Thank you for any replies.
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No C6's with factory catch can. GM deemed them not neccery, since it would be a mantain thing with have to drain them before they over flowed, and the fact that both the valley cover and valve guide covers have baffle system that do a pretty good job at oil separation (so long as you are not playing rev ranger with the motor).
The problem with a catch can is a leak it it from the can not being tightened correctly during a oil drain of it, or in it hosing not tight and air leaking instead. This allows un-metered air into the intake manifold that the MAF does not see/meters, and causes lean condition problems at idle instead. Also, if you don't empty the catch can before it becomes filled with oil, then the oil on the can will puke a great deal of oil into the intake manifold at once instead.
To add, to do a catch can correctly, you need to catch both the clean side and the dirty side as well.
The problem with a catch can is a leak it it from the can not being tightened correctly during a oil drain of it, or in it hosing not tight and air leaking instead. This allows un-metered air into the intake manifold that the MAF does not see/meters, and causes lean condition problems at idle instead. Also, if you don't empty the catch can before it becomes filled with oil, then the oil on the can will puke a great deal of oil into the intake manifold at once instead.
To add, to do a catch can correctly, you need to catch both the clean side and the dirty side as well.
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From: Bergen County, NJ
I've had my Catch Can on for about 30K miles and several high rev 1/4 mile passes. No problems at all.
I extract about 1/2 inch of oil from it every time I change the oil.
One small problem; the bottom kept coming loose and dripping oil, so I put J-B Weld around the inside bottom perimeter, and I extract the collected oil with a turkey baster.
Someone told me that the Catch Can could affect upper cylinder lubrication, but I have no idea if that's true.
I extract about 1/2 inch of oil from it every time I change the oil.
One small problem; the bottom kept coming loose and dripping oil, so I put J-B Weld around the inside bottom perimeter, and I extract the collected oil with a turkey baster.
Someone told me that the Catch Can could affect upper cylinder lubrication, but I have no idea if that's true.
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Drifting
Joined: Oct 2004
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I bought a nifty little unit from Corvette Mods. $49.99. Have one on both the C5 and C6 GS. Works great .... with a glass bowl so you can see the oil accumulation.
Last edited by jost6453; Apr 6, 2018 at 09:38 PM.
Drifting
Joined: Dec 2016
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Probably nothing major without a catch can. I have heard that oily intake air does effectively lower octane though so you -may- lose some power. Probably very minimal unless you have bad amounts of blowby. I did it mostly to keep oil off of the intake tract.
