Installed a PCV catch can.
04-16-2012, 08:52 AM
#11
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I have run two oil catch cans on two previous vehicles. Built 2004 GTO and a Mustang before that. You setup looks nice and I have a catch can sitting in the garage that my father gave to me. One thing that may help you out, looks like you could eliminate a lot of extra hose by turning the catch can forward about 90degrees or more. Probably won't make a difference in performance but you won't have a lot of hose hanging down in the engine bay.
04-16-2012, 11:28 AM
#12
JK Jedi Master
Thanks! Unfortunately, yes, it's a manual process to monitor the oil the device catches. On this unit, there is a valve at the bottom that is used to drain the caught oil. It will hold a fair amount of oil - about 2oz pretty easily.
Regarding that small pilot hole... During my install here, I had fully removed the stock PCV valve, taken a look at it, and put it back in. I completely cleaned it up while doing so. I took to JK for a trip to the hardware store for some fittings, returned, and disassembled the tubing again. This time, there was a small puddle of dirty oil forming at the top of the valve. That's about the first time I paid attention to that hole. I happened to put the valve in with the hole towards the front of the block. Oil pooled at the rear of the PCV valve recess in the valve cover (due to the slant of the motor). I took the valve out and spun it around so the hole was facing the rear of the block.
I'm not good with fluid dynamics or whatever science is involved here, but I thought the difference in pressure from the nozzle (PCV valve nipple) to the larger void (the main tubing) would promote the oil to condense in the tube. If it doesn't maybe it's just dumb luck that oil is getting caught there
Regarding that small pilot hole... During my install here, I had fully removed the stock PCV valve, taken a look at it, and put it back in. I completely cleaned it up while doing so. I took to JK for a trip to the hardware store for some fittings, returned, and disassembled the tubing again. This time, there was a small puddle of dirty oil forming at the top of the valve. That's about the first time I paid attention to that hole. I happened to put the valve in with the hole towards the front of the block. Oil pooled at the rear of the PCV valve recess in the valve cover (due to the slant of the motor). I took the valve out and spun it around so the hole was facing the rear of the block.
I'm not good with fluid dynamics or whatever science is involved here, but I thought the difference in pressure from the nozzle (PCV valve nipple) to the larger void (the main tubing) would promote the oil to condense in the tube. If it doesn't maybe it's just dumb luck that oil is getting caught there
One is a mesh material for the oil vapor to form droplets.
The other is some sort of baffle inside to cause the air flow to take a sharp turn, which will make the oil separate from the flow.
04-26-2012, 01:22 PM
#13
JK Super Freak
Thread Starter
Thanks for the suggestion! I did use a lot of hose, but it's not as messy as the pictures might suggest. They're pretty stiff hoses which is why I have them routed funny -- not to mention I was taking into account the routing of the original PCV hose I tapped into; was having a hard time getting things adjusted nice. The new PCV lines stay pretty horizontal to the connections and leave a lot of room to get underneath to access the drain valve. Next time I'm tinkering I'll see if I can trim them up.
04-26-2012, 01:38 PM
#14
JK Super Freak
Thread Starter
A general update...
Been running the catch can for a few weeks now(?). Just did its first in-car drain, and drained enough oil to fill the bottom of a dixie cup about 1/4". Dirty brown oil. Roughly guessing about a week and a half of mixed driving totaling about 300-350 miles.
The hiss the can makes at idle and during certain throttle settings is a little annoying when you've got all the windows up and the radio off. I'm looking to resolve or lessen it. I'm not sure if it's the air the can is processing, or if it's originating somewhere else in the PCV plumbing - either way, because I have the can firewall-mounted, the firewall is amplifying the sound. It's hardly noticeable holding the catch-can up to your ear, with the motor running.
Performance and detonation -- big improvements here. I would pretty confidently say that detonation has been reduced by 90%. Still get a few light-light "tickles" under heavy loads when hot, but nothing like before. Because there is little if any knock retard, throttle response is great and power is there when needed. Much easier to rev-match gears too. I'm running a tune, axle back exhaust, and the catch-can. Between these three mods, there is a LOT more bottom end power in the motor.
I mentioned that I was concerned about the PCV valves operation might have been hindered or changed by the PCV can. I dont think that's the case. The engine stumbles bad when a leak or full blockage of the PCV line is introduced. There is/was no change in idle when I installed the can.
I'm still trying to evaluate if the hiss is related to the perception that throttle response off idle has suffered. The hiss SOUNDS like a vacuum leak, but the motor runs pretty darn good. If I didn't hear the hiss, I don't think I'd notice any change in throttle response. The hiss kind of gets in my head...
Been running the catch can for a few weeks now(?). Just did its first in-car drain, and drained enough oil to fill the bottom of a dixie cup about 1/4". Dirty brown oil. Roughly guessing about a week and a half of mixed driving totaling about 300-350 miles.
The hiss the can makes at idle and during certain throttle settings is a little annoying when you've got all the windows up and the radio off. I'm looking to resolve or lessen it. I'm not sure if it's the air the can is processing, or if it's originating somewhere else in the PCV plumbing - either way, because I have the can firewall-mounted, the firewall is amplifying the sound. It's hardly noticeable holding the catch-can up to your ear, with the motor running.
Performance and detonation -- big improvements here. I would pretty confidently say that detonation has been reduced by 90%. Still get a few light-light "tickles" under heavy loads when hot, but nothing like before. Because there is little if any knock retard, throttle response is great and power is there when needed. Much easier to rev-match gears too. I'm running a tune, axle back exhaust, and the catch-can. Between these three mods, there is a LOT more bottom end power in the motor.
I mentioned that I was concerned about the PCV valves operation might have been hindered or changed by the PCV can. I dont think that's the case. The engine stumbles bad when a leak or full blockage of the PCV line is introduced. There is/was no change in idle when I installed the can.
I'm still trying to evaluate if the hiss is related to the perception that throttle response off idle has suffered. The hiss SOUNDS like a vacuum leak, but the motor runs pretty darn good. If I didn't hear the hiss, I don't think I'd notice any change in throttle response. The hiss kind of gets in my head...
04-27-2012, 07:04 AM
#15
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Good information. I have always said that oil was a big culprit in the detonation on the oil consuming motors (Im having issues with both). If you havent done this yet, I highly recommend trying to clean the carbon from the motors. The valves on these motors are notorious for heavy carbon issues. A combintion of seafoam and Chrysler combustion chamber cleaner treatments helped with my pinging issues
05-10-2012, 06:49 AM
#16
JK Super Freak
Thread Starter
Quick follow up. Tried some things to try to reduce/remedy the hiss...
1) Drove the PCV valve a little deeper into the valve cover. It was somewhat loose when it was in it's correct position in the valve cover (The rubber grommet seems to have shrunk.) I drove it a little deeper to make a better seal.
2) Shortened those hoses. Probably cut 8" off each one.
3) Removed, cleaned, reinstalled catch-can packing. The packing just looks like a bunch of spiraled stainless shavings cleanly cut using a lathe. It's held in place with a screen and snap ring. I should have taken pictures. Blasted things out with carb cleaner - had some varnish and crud from my previous vehicle.
The hiss is reduced by about 50%, but still present. Not sure which of the three made the improvement. I'll still poke at it when I have time.
1) Drove the PCV valve a little deeper into the valve cover. It was somewhat loose when it was in it's correct position in the valve cover (The rubber grommet seems to have shrunk.) I drove it a little deeper to make a better seal.
2) Shortened those hoses. Probably cut 8" off each one.
3) Removed, cleaned, reinstalled catch-can packing. The packing just looks like a bunch of spiraled stainless shavings cleanly cut using a lathe. It's held in place with a screen and snap ring. I should have taken pictures. Blasted things out with carb cleaner - had some varnish and crud from my previous vehicle.
The hiss is reduced by about 50%, but still present. Not sure which of the three made the improvement. I'll still poke at it when I have time.
05-10-2012, 05:25 PM
#17
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Originally Posted by yo_marc
Quick follow up. Tried some things to try to reduce/remedy the hiss...
1) Drove the PCV valve a little deeper into the valve cover. It was somewhat loose when it was in it's correct position in the valve cover (The rubber grommet seems to have shrunk.) I drove it a little deeper to make a better seal.
2) Shortened those hoses. Probably cut 8" off each one.
3) Removed, cleaned, reinstalled catch-can packing. The packing just looks like a bunch of spiraled stainless shavings cleanly cut using a lathe. It's held in place with a screen and snap ring. I should have taken pictures. Blasted things out with carb cleaner - had some varnish and crud from my previous vehicle.
The hiss is reduced by about 50%, but still present. Not sure which of the three made the improvement. I'll still poke at it when I have time.
1) Drove the PCV valve a little deeper into the valve cover. It was somewhat loose when it was in it's correct position in the valve cover (The rubber grommet seems to have shrunk.) I drove it a little deeper to make a better seal.
2) Shortened those hoses. Probably cut 8" off each one.
3) Removed, cleaned, reinstalled catch-can packing. The packing just looks like a bunch of spiraled stainless shavings cleanly cut using a lathe. It's held in place with a screen and snap ring. I should have taken pictures. Blasted things out with carb cleaner - had some varnish and crud from my previous vehicle.
The hiss is reduced by about 50%, but still present. Not sure which of the three made the improvement. I'll still poke at it when I have time.
05-11-2012, 06:21 AM
#18
JK Super Freak
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