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I've been having oil leaking out of my seals and I'm finally going to address the issue. The leak isn't major, its just over time it just makes my engine look dirty.
I'm currently running a OEM GTX323 check valve, and I'm currently at 17psi.
My current setup is:
GTX323 check valve -> catch can -> manifold
Breather going straight to atmosphere
What I want to do:
Enlarge PCV port to AN10 w/ stronger aftermarket check valve -> Catch can -> manifold
Enlarge breather port to AN10 -> catch can/breather -> VTA
or
Block stock breather port. Tap the top side of the breather port with an AN10 port -> catch can/breather -> VTA
Or is the gtx323 strong enough to hold 17-20psi? I just want to eliminate any positive crank case pressure I currently have. Before you comment, yes I know that the stock breather port is probably the cause of the positive crank pressure. I just want piece of mind that I shouldn't have ANY major positive crank pressure to cause seals leaking with my new setup.
here’s a few of the radium check valves. Designed a little like a PCV. I imagine the larger one is built similar. They have another with a built in PCV, but besides being -10orb on one side, I’m not sure it flows any more than a Miata sized one.
I would keep a PCV valve even if you add a check valve, the sealing plunger has two sealing faces.
Correct me if I'm wrong. You'd only want to keep the oem pcv valve in place if I'd run a simple one way check valve. But with something like curly suggested, I wouldn't need to run the oem pcv alongside with the radium pcv/check valve.
Originally Posted by curly
here’s a few of the radium check valves. Designed a little like a PCV. I imagine the larger one is built similar. They have another with a built in PCV, but besides being -10orb on one side, I’m not sure it flows any more than a Miata sized one.
Thanks for the photos!
For the PCV, my concern isn't necessarily flow, as it only flows in vacuum which isn't much of a load. My main concern for the pcv, is it leaking/breaking down under medium amount of boost.
Opening up the breather to an AN10 line to a breather box, should theoretically eliminate positive crank pressure correct?
If you are looking to keep push-on hoses and not change everything over to -an, Boomba makes some really nice vacuum check valves. I really like using them. They come in everything from 1/4 to 3/4"
If you are looking to keep push-on hoses and not change everything over to -an, Boomba makes some really nice vacuum check valves. I really like using them. They come in everything from 1/4 to 3/4"
On my turbo vehicles I run a PCV with one of these check valves to prevent boost pressurizing the crankcase. The opposite breather vented to atmosphere through a filter has been fine for me.
They not really that expensive. That was just the first link that showed up in google. I normally find them for $35 retail price.
Those cheap fuel check vales are not rated to open under vacuum. They have a MUCH higher cracking pressure. I've used a lot of different check valves in a lot of different configurations and the boomba ones are the only ones that I can personally recommend.
On my turbo vehicles I run a PCV with one of these check valves to prevent boost pressurizing the crankcase. The opposite breather vented to atmosphere through a filter has been fine for me.
Did you drill your breather port bigger?
I also have a filter on my breather port, but no additional check valve for the pcv. Just the gtx323 pcv.
Curious if my pcv Is causing my crankcase pressure...
here’s a few of the radium check valves. Designed a little like a PCV. I imagine the larger one is built similar. They have another with a built in PCV, but besides being -10orb on one side, I’m not sure it flows any more than a Miata sized one.
Do you use the radium PCV?
I made the changes to my PCV system and my manifold catch can fills up at a alarming rate now, which is about a cup worth after driving 20ish minutes. (Never filled up when running old stock GTX setup)
However I did fix the issue of oil slowly seeping through my seals due to positive crank pressure. Radium check valve I'm using: https://www.drifthq.com/products/rad...32929772797999
A few things I suspect might be the issue, but want a second opinion before I start messing with the car again.
When I removed the covers from the valve cover, I cleaned off all RTV sealant and didn't bother reapplying as I didn't think it really needed it.
Should the PCV be angled upwards instead of downwards like how I have it currently? (See attached pic)
What I did: Enlarged PCV port to AN10 w/ radium PCV -> one way check valve -> Catch can -> manifold Enlarge breather port to AN10 -> catch can/breather
Maybe I'm missing something in the whole PCV system...
The PCV being connected to manifold vacuum allows a ton of water vapor to be pulled from the crankcase. That's a very good thing for a street car. I'm not really surprised you're filling your catch can if you're pulling everything through there.
Catch can on the exhaust side vent is fine. Catch can on the intake side with a pcv is going to be problematic.
The PCV being connected to manifold vacuum allows a ton of water vapor to be pulled from the crankcase. That's a very good thing for a street car. I'm not really surprised you're filling your catch can if you're pulling everything through there.
Catch can on the exhaust side vent is fine. Catch can on the intake side with a pcv is going to be problematic.
Before I made the changes, it wouldn't fill up nearly as fast as it is now. (Running catch can with the gtx valve)
So I'm assuming it has something to do with the radium pcv.
What would happen if I just plugged the intake side?
I had ridiculous oil consumption and filling of the can till I reintroduced a "stock" PCV valve. I had just grabbed something off the shelf at autozone that looked like it would flow more, then stuffed a 1/2" barb into the stock grommet on the cover and stuck the PCV inline, after my catch can. The catch can has a pressure release and opens to atmosphere somewhere over a few PSI, so that both sides of the valve cover are essentially free flowing while the PCV is closed. Now it just fills with water with maybe a 1/4" of sludge on top and I'm wishing I could find a cheap water "cooled" one so I can boil all that crap out instead of having to drain it constantly.
Like I said before, I don't think stock PCVs are open in full on vac. Theoretically they are tuned to the engine, or at least the two closing pressures. I have no hard data other than my experience with autozone crap, so YMMV.
Plug the other side and PCV is essentially useless. Your intake manifold would be pulling a vacuum on the block. It would work better if there were an air leak, the driver's vent, so that you can suck clean air through and use that to move the crap in there out. That's the P in PCV.
If that's all oil you need to be checking the health of the engine. The liquid collecting in there should be 90+% water.
Will double check the compression once I have time, but I doubt the health of the engine is in question as car still pulls like a rocket ship. This issue only came up once I tried being fancy with the PCV system... With the old setup it did collect some oil/water, but It was no where near as much as it is now, so I'm assuming the radium pcv flows way too much for our engines.
Originally Posted by deezums
I had ridiculous oil consumption and filling of the can till I reintroduced a "stock" PCV valve. I had just grabbed something off the shelf at autozone that looked like it would flow more, then stuffed a 1/2" barb into the stock grommet on the cover and stuck the PCV inline, after my catch can. The catch can has a pressure release and opens to atmosphere somewhere over a few PSI, so that both sides of the valve cover are essentially free flowing while the PCV is closed. Now it just fills with water with maybe a 1/4" of sludge on top and I'm wishing I could find a cheap water "cooled" one so I can boil all that crap out instead of having to drain it constantly.
Like I said before, I don't think stock PCVs are open in full on vac. Theoretically they are tuned to the engine, or at least the two closing pressures. I have no hard data other than my experience with autozone crap, so YMMV.
Plug the other side and PCV is essentially useless. Your intake manifold would be pulling a vacuum on the block. It would work better if there were an air leak, the driver's vent, so that you can suck clean air through and use that to move the crap in there out. That's the P in PCV.
Hmmm, I think the radium one is fully open during any sort of vac. Maybe this is what is causing my issue.
09-27-2021, 02:13 PM
Aftermarket check valve for PCV
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