The REAL reason why the FS burns oil

Digging up an old thread because I think I found the problem with my setup. I finally got sick of dumping out my catch can every couple months and decided to take off the red valve cover and then use the black one that was otherwise unmodified.

Unfortunately, the black one did not come with baffle covers. So I had to remove the covers from the red one and put them on the black one. Tragically, when I broke out my RTV, it was pretty much dried up. Rather than just going to the store and buying more like a normal person, I struggle to lay down the half dried up RTV as quickly as possible, which splits open the end of the tube, and I end up covering more of my hands and forearms with the goop than the actual valve cover.

Well anyway, I break out some toothpicks and clean it up as best I can and it doesn't look too bad. So I decide to slap on the covers and see how it goes. After waiting the hour to dry, I check to see if I had made a good seal by putting my finger over the crankcase hole and blowing on the breather tube. I wasn't even close. Air leaks all over the place.

But that got me thinking, maybe when Brian RTV'd my red valve cover, he didn't make a good seal either. There are a few suspect areas where the RTV was very sparse. I wish I would have thought of this before I removed the covers in the first place, but I put them back on the red cover out of curiosity. To compensate, I also pushed down on the covers as I blew, and the two suspect areas with no lip of RTV were definitely leaking.

All bets are off since I ruined the seal by removing them, but I still think this is the root cause of my excessive amount of air being pulling in from the breather tube during idle and my catch can filling up so quickly. Blow-by doesn't have that much oil in it. My PCV side catch can has grabbed at least 3 quarts of oil in the last year, but the breather side can is still bone dry. The inside has an oily film of course, but not a drop has ever come out.

Actually, you would think blow-by would be much worse under boost and the breather side would collect more. Maybe if you only drove on the highway, you'd expect to collect more oil on the PCV side than the breather, but my car doesn't see that much highway cruising. Certainly not 3 quarts to 0 ounces.

But if you had a vacuum leak inside your valve cover and the PCV could draw air directly from the breather, that air in the valve cover would collect a bunch of oil on its way to the PCV.

So going back to this thread. I think drilling a hole in the breather side of the baffle is a bad idea. If you were to run unmetered air to the breather tube, such as putting a filter directly on the cover, I am pretty sure you'd eventually max out your trims and throw a CEL. Even though the stainless steel filter is working, it is filtering much more air than it should be, and probably why TheMAN is still losing oil. Much less of course, but ideally, it should be none.

Before I installed the catch cans, I've never noticed any decrease in oil. I found trace amounts in my intake, which led me to the catch can "solution," but I think in a healthy car there should be very little. I am wondering if that seal is ruined over time even on stock cars, and responsible for the excess oil burning a lot of members see.

Catch cans are never a bad idea, I just wish someone would have made a little cheap in-line one that didn't require all the hoses, fittings, and brackets of the CR3 setup. More than anything, I just wish I wouldn't have sent the cover to them in the first place.
 
Catch cans are never a bad idea, I just wish someone would have made a little cheap in-line one that didn't require all the hoses, fittings, and brackets of the CR3 setup. More than anything, I just wish I wouldn't have sent the cover to them in the first place.

I had the same crap cans and stuff done to my VC and nothing but issues same as a few other people. to clarify things it was not a CR3 setup it was another guy who made everything CR3 was just the middle man. Also the company that made them no longer makes them as hes posted they were a mistake.. My CR3 setup that is currently the car has never given me issues like the drink can setup.
 
Well I don't think anything is fundamentally wrong with Brian's setup. It does do a pretty good job of separating the oil. While I have had to empty my PCV can every 1k miles, I haven't been burning any.

The AN fittings are overkill and add major cost to the system. While he claimed it is necessary for high boost applications, boost closes the PCV, so the connection from the IM to the PCV is the only one ever under any pressure, and the IM end is still being held on by a hose clamp unless you modify the IM as well. Even then, there are a dozen other vacuum hoses on the IM that are more likely to pop off first.

The cans are very thin aluminum and are unnecessarily large, but they look fine. I had more trouble finding a good location for them and fabricating a bracket than I did with the overall quality.

Boring out the breather side passageways is a bit of a mystery to me. If the crankcase was getting so much blow-by that the passageways were inadequate and the oil in the crankcase started to froth, I would think you have much more serious issues. But perhaps with high boost engines, this is a possibility.

I think it all comes down to the making sure the breather side and PCV side are separated by the crankcase. I am tempted to find another VC and snag the baffle plates from it, and keep my red VC and catch can setup. But that would be a pretty big hassle, and if I am wrong, and there is something I am missing and I still have to empty that can every 1k miles, it would be a huge waste of time.

I'd love to see a diagram of the airflow through the crankcase and back up through the block and heads to the VC. It must be fairly restrictive otherwise why would you bother separating the breather side baffles from the rest of the VC.
 
I've done a bit of research (google image search) and I am still not sure how the blow-by or fresh air for that matter gets from the crankcase to the valve cover.

crankcase1-L.png


There are some obvious differences between the SR20 and the FS. Our fresh air path is internal and has no catch can, just those 3 baffle chambers. Judging by the spotlessness of these chambers on my VC, and the emptiness of my breather side catch can, they don't collect much oil anyway. My baffles aren't even oily after about 12k miles.

The biggest difference is the pathway through the timing chain area. We don't have that path. But there are quite a few holes in the head where oil could run back down to the block. Three on the intake side, and two on the exhaust side, along with the one that connects to the fresh air chambers. Does air travel up these tubes as oil drains back down?

Also, where exactly does the oil even get pumped into the valvetrain? Does the oil just fill the valvetrain or does it spray?

I'd love to do my own engine build at some point, but I've just never owned a car where it made sense to do it since engines tend to outlast the rest of the car.

Here is a picture of my valvetrain, high res, so just a link : http://i.imgur.com/pClVQTd.jpeg
 
Sorry to necropost but I'm in the middle of this right now. I picked up a spare valve cover from a salvage yard and am working on the cleanup this weekend.

So going back to this thread. I think drilling a hole in the breather side of the baffle is a bad idea. If you were to run unmetered air to the breather tube, such as putting a filter directly on the cover, I am pretty sure you'd eventually max out your trims and throw a CEL. Even though the stainless steel filter is working, it is filtering much more air than it should be, and probably why TheMAN is still losing oil. Much less of course, but ideally, it should be none.

I'm curious about this. Does anyone else have any thoughts about drilling that extra hole? What kind of potential problem could there be with not drilling that extra hole?
 
Sorry to necropost but I'm in the middle of this right now. I picked up a spare valve cover from a salvage yard and am working on the cleanup this weekend.



I'm curious about this. Does anyone else have any thoughts about drilling that extra hole? What kind of potential problem could there be with not drilling that extra hole?

I think you'd run the risk of more oil being dumped back into your intake manifold or catch can if you don't drill the hole. I did this mod about a year ago and it really did cut down on my oil consumption.
 
Sorry to bring back this old thread. BUT, I just have a few questions about this modification.

1.) Anybody have this mod installed for a few years who can provide positive or negative long term feedback?

2) Are there any known drawbacks to having this mod installed?

3) Roughly speaking, by how much does this reduce oil consumption?

4) Is this a safe permanent mod, or would I have to open the valve cover and replace the oil separator scrub pads periodically?

5) Is this mod recommended only for the Mazdaspeed Protege(turbo) only, or is it beneficial to the regular Naturally Aspirated(FS-DE) guys as well?


Any info or feedback would be greatly appreciated. Thanks in advance for the help guys!
 
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