Question, my buddy was telling me he noticed oil and carbon deposits in his oil/air separator. The amount of oil maybe two tea spoons combined with carbon deposits. His 454 engine is highly modified that outputs about 650 HP. However, it's a new rebuilt engine with alum heads with only 20 hours of run time. He doesn't want anything except gas and air to go into his intake, but with a PVC, I don't see how you can avoid NOT getting oil and carbon deposits coming from the crankcase pressure. What do you guys think? Normal condition for his new engine with just 20 hours of run time??? I think so, but it's a guess on my part. VET (Navy)
If the PCV is properly baffled, and the engine does not have excessive blow-by, there shouldn't be oil or carbon from the PCV system. There IS NO crankcase pressure with a functioning PCV system. There's only enough pressure difference to allow air flow through the valve. Faulty baffling, or excess blow-by could change that. Tell your buddy that crying about a couple of teaspoons worth of oil in a catch-can, over 20 hours of run time is obsessive, but he could try additional baffling at the PCV valve.
Interesting, I never put a thought to this subject. So, air flow only through the PCV, no oil or carbon deposits. I can understand that. Thanks. So, you are saying, the oil & carbon deposits in his oil/air catch-can are more than he should be seeing? I thought this is the function of a catch-can? He noticed some oil when he removed his carb and looked down his intake. He wasn't expecting to see any of that. So, you think he may have a problem? You think baffling at the PCV can help this issue. If all this is NOT a big issue, i'am not sure it's worth telling him about it. Do you? Thank you for your help and advice, it's always appreciated.
Filtered air, crankcase "fumes" including water vapor and blowby. Removing fuel fumes, combustion gasses, water vapor, and whatever oil vapors are being created by the lighter fraction of the base oil boiling out of the oil mixture. But by far, the greatest percentage is filtered air including whatever humidity is present in the atmosphere at the time. No, I'm saying that two teaspoons of liquid in 20 hours of run time are probably normal and nothing to be concerned with, even if it did go into the intake manifold instead of being trapped in the catch-can. Those two teaspoons of liquid might be actual oil, which could indicate insufficient baffling--but it's more likely that they're petroleum fumes dispersed in water (condensed water vapor). Is this "really" engine oil, or is it fuel residue from intake reversion? Perhaps it is oil, pulled out of the lifter valley via leaking intake gaskets. Is he seeing "traces" of oil, or big ol' puddles? No, I don't. I think he's getting wound-up over nothing; or at most is looking at a PCV valve baffle issue for the liquid in the catch-can. I can't say about the "oil" in the intake manifold. Depends on quantity, I guess. Kinda depends on whether he's really seeing OIL in the catch-can and intake manifold, or if he's seeing petroleum residue from fuel, or water vapor, or something other than (or in addition to) actual engine oil. Might as well put his mind at rest...or at least have him experiment with better baffling. If this was me, I'd have never put a catch-can on the thing in the first place. That wasn't the impression I got in your other thread. I haven't been back to that one since you told me to not post there any more. Did I misunderstand?
Schurkey, Please don't take it personal, there are going to be times on this forum where we both "agree to disagree". It's obvious to me, something you said I didn't agree with, and I got po'ed. I'm a very nice guy when you get to know me, but I do have a temper and sometimes I say or do things that I shouldn't. To try and smooth things over, I apologize, Iam sorry. Sometimes we all can get into a snip and say thinks like you did on this post (Tell your buddy that crying about a couple of teaspoons worth of oil in a catch-can, over 20 hours of run time is obsessive.) That's uncalled for, my buddy and I have been friends since our Navy days 53 years ago. As a recap to this forum, I have gotten a ton of great advice and guidance from a lot of members on here. For which I'm very applicative for. It's not possible to know every detail when it comes to the automotive field. I'm primary a SB Chevy guy but I love the Buicks. I remember all the Buicks my father owned, and I got my driver's license when I was a teenager (a very long time ago) in his 1964 Wildcat, fantastic car. I had the opportunity to purchase a 1970 Buick GS 455 and I went for it. I'm good, if you are?? VET (Navy)
I know you're a fine person and I appreciate your automotive advise and guidance. Just so you know, we are almost completed with the high water temperature issues. We ordered a Griffin aluminum radiator yesterday. Like I was informing you a while back, this work is a process we have been working on and we are getting there, maybe to slow. The copper/brass radiator I purchased a week ago was found to be defective. Ran 20 degrees about my original radiator. I light of this situation, I decided to purchase a alum radiator that was recommended by Larry the Wiszard. I will finally have a great driving Buick. Again, thank you for your help for my friend's intake oil issue. VET (Navy)
What constitutes "carbon deposits?" Is it black chunks, black soot or oily black liquid? The PCV system is designed to draw off gases that are created inside the crank case, from hot oil fumes to spent combustion gases that bypass the rings. No engine is 100% sealed between the crankcase and the combustion chambers. They all have some leak down and bypass. If the PCV valve is situated in such a way as to be exposed to direct oil splatter, then, as was stated above, it needs a better baffle system or it will draw in more oil than it should. What you're talking about seems normal. If he doesn't take it on long enough drives to burn off the condensation that builds up in an engine, I suspect he'll see more than not. Frankly, an oil catch can on a naturally aspirated engine is not needed. 2 tsps in 20 hours is only 20 miles if he was actually driving it. At 1 tsp per 10 miles, that would be almost 2,000 miles to a qt of oil. That's not much oil at all. Certainly not enough to cause it to smoke.
Thanks, it's oily black liquid. The 20 hours engine run time is driving time. This is a newly rebuilt engine that is located in Hawaii. So, small roads and low speed limits. I suspect you are correct about condensation being a major factor. Thank you, I'll pass your information to my buddy.
Your reason and results are the very reason why my buddy uses an oil separator system too. He also uses an water methanol system that does a great job of keeping his pistons and plugs super clean.
Vet, Couple things I can think of. I like the idea of a catch can inline. Help keep intake tract and especially intake valves and piston tops cleaner. If there’s oil in the intake. Im wondering if it’s from the intake gasket not properly sealing. Is the a Chevrolet? You mentioned a 454. The choices in intake gaskets and gasket thicknesses is endless. Just a few ideas. Hope alls well otherwise.
Water methanol could wash down oil if not in exact measurements and could be another possibility. Just saw this when I replied. Might have to due process of elimination.
That’s what I figured. What cylinder heads? Did he have them checked at a machine shop? And gasket sizes and thickness are endless.
He has a system where he can meter the amount of water methanol that goes into his engine. At this point in time, he doesn't seem to think it's a concern now. The oil he is seeing seems to be mixed with carbon deposits. Thank you for pointing out these possible issues. I will pass along to my buddy.
Yes he had everything checked out. The heads are Bodex, not sure I spelled it correctly. The heads are USA manufactured. He doesn't buy Chinese junk.
Figure he bought race rites. Excellent head. There are 3 thicknesses of intake gaskets available and different compounds. Did he retorque intake? Possible issue. And like said mixing meth water could wash out oil. Just some ideas.so could be fuel or oil in intake.
My buddy is 74 and had been racing and wrenching on high performance cars since he was 15. I know he re-torqued the heads. What it looks like is a combo of carbon deposits and a film of oil residue mixed with water methanol. The oil film may be coming from the PCV from the crank case venting through the PCV. The carbon residue is making it look very dark. Pulled the plugs and that look fantastic. So, there doesn't seem to be a problem. He's making around 650 HP. Thank you for your trouble shooting efforts, it's appreciated. VET (Navy)
I almost forgot. I read an article that said to keep water methanol from washing away cylinder oil, mix a small amount of soluble oil with the water methanol. I think I remember about 1%.
