I am definitely sucking oil through my pcv valve. I have an industrial i6 300 and I was trying to figure out why my exhaust started smoking. I freaked out as I just got this thing on the road and thought it was coolant but nope. It is definitely my pcv valve. I pulled off the hose and it was soaked in oil on the inside so what I did to confirm was make a catch can with vacuum nipples out of a clear bottle. I hooked one side to the pcv and one side to manifold vac and I can see the oil droplets being sucked and settling at the bottom. I just filled the bottle with mechanic wire and it seems to catch most of it. I have a brand new pcv valve too. It definitely gets worse after it's warm and the oil is thinner. Anyone ever experienced this? It has brand new i6 level of blowby as it should though I cant see anything smoky like my old tired one had. All I could find was people saying it wasn't the pcv valve but in my case it is. I think what's happening is that I have so much oil pressure even at idle that it's filling the valve cover a good bit and or maybe there is no baffle in there? I do have another valve cover but it's cold outside so I guess it's catch can for now

 

And what is that as I have never seen it posted what "brand new i6 level of blowby as it should" would be?

So what is the oil psi cold & hot on this motor?
High oil psi would not should not fill the valve cover with oil.
If it is filling with oil then the oil drain back holes are plugged and not letting the oil drain back.
The other sign if this was so is no oil psi as it would all be up top and not in the oil pan where it would be picked oil by the pump and pumped through out the motor. So look else where for the issue.


I think you may have found the problem, no baffle where the PCV fits in the cover and that mostly happens with after market covers.
Could look down the hole where the PCV goes on both covers and see if there is a baffle in one and not the other.

Let us know how you make out.
Dave ----

 

It should have a baffle beneath the PCV grommet and a divider midway down the valve cover to direct incoming make-up air into the crankcase and back out the PCV. The devil is in the details.

 

Do you have a breather hose or breather cap on the other end of the valve cover? If not, you are building up pressure inside the engine and pushing the oil out the PCV valve. All PCV air being sucked out has to be made up with fresh, filtered air coming in.

 

I do have a breather in the front hole near the oil cap. Just one of those push in filter types because the air filter I'm using doesn't have a provision for the original one with the hose. Pcv is in the same spot as all other i6. The valve cover is the stock grey industrial one. Still has it's badge. Oil psi is 85 at cold and 55 hot at idle. When I gun the gas it goes up to 90 at 3000rpm. I think it must have a super high flow oil pump on it because the pan does take 8 quarts.
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I do know where it came from as well. It's interesting actually. I asked him what the heck it even was and he said it came off a pump at small local airport and it was for de-icing the planes. It had two pumps on it one on a clutch on the bell housing and another on the pulley side. The guy said it got rebuilt and they never used it as the airport replaced it with a new machine(something was wrong with the controls on it) and I believe it because the pan was absolutely sparkling clean inside and I wanted to check the crank to see if it was forged and yep it is. It's from the 60s. I got to save the cool mechanical temp gauge out of the machine as well as everything on the skid. The carb was unusable though as the throttle was completely backwards! It had an electric actuator that pushed on the lever and it sat in a different orientation than a normal Carter yfa. I didn't know you needed i6 power to de ice planes lol! I still have all the parts including the carb if anyone needs any of em.

 

If that is the original valve cover, it could be your problem since I suspect the industrial engine didn't use a PCV, and if so, there would be no baffle. If it did, try pulling the front breather out of the cover after the engine has ran a while to see if there is any build up of vacuum or pressure. Could also be the front breather is not passing enough air through it.

 

Why wouldn't of they used a pcv? They definitely did because the oil bath cleaner has provisions for it but I think you might be onto something there. I think the paper push in intake I have there might not be letting enough air flow through there. I'll mess with it once it gets warmer and just run the catch can for now. It's not like it's heaps of oil it's just droplets. Maybe I could just use the hot air choke inlet on the carb because I changed it to manual and it's just capped off. Since it's just before the air filter on top and run the hose there and see since it only takes a minute to do. Didn't even think of it till now.

 

If there is a hose from top of the air cleaner, that was the vent hose to the valve cover, not for the PCV. There may or may not have been a factory PCV valve. Industrial engines had different emissions rules. If you didn't find a port under the carb or on the intake for it, then most likely there was no PCV valve at all.

If you did have a port, and that is what you're using, then the front of the valve cover would most likely have had a wist off cap with a vent hose off the top to the top of the air cleaner to let the engine get clean air.

 

the PCV is not for emissions lol. its so you dont blow out your seals and stuff and yes even this 60s block originally came with it. The oil bath air filter had an elbow with the breather hose nipple on it and it was hooked to the manifold vac just below the carb. Now I have another odd thing going on...after changing the oil im getting lifter tick but only happens once warm. I seen other people get this here but its hilarious after just changing the oil. Maybe I need a zddp additive. It goes away when I gas it though.

 

https://www.underhoodservice.com/pcv-valve-facts/

1. The first vehicle to get a positive crankcase ventilation (PCV) valve was the M5 Stuart tank in WWII, which was made by Cadillac. The valve replaced draft tubes that might suck water into the engine while crossing rivers.

2. In 1952, Professor A. J. Haagen-Smit of the California Institute of Technology at Pasadena theorized that unburned hydrocarbons were a primary constituent of smog. In 1958, it was discovered that road draft tube was responsible for almost half of the unburned hydrocarbon emissions that cause smog in California.

3. The PCV valve was the first emissions device ever. Secondary air injection, or the “smog pump,” was next.

4. GM gave away its patents for the PCV valve to the rest of the automotive industry to use royalty-free.

5. In California, the PCV valve was mandatory on all new vehicles for 1961. By 1964, the majority of vehicles sold in the U.S. had one as standard equipment. It became mandatory on all vehicles in 1967.

6. The spring inside the PCV valve is calibrated for the vehicle’s manifold vacuum and crank case pressures. This spring weakens over time, causing the valve to fail.

7. In 1967, American Motors made the claim that drivers could go 4,000 miles between oil changes due to the implementation of the PCV valve. The PCV valve helped to extend the interval because it helped remove water condensation in the crankcase.

8. Shaking and listening to a PCV valve does not mean a thing.

9. Cleaning a worn PCV valve typically does not do anything. It just means you now have a clean, worn-out PCV valve.

 

I know a lot of places say that but meh. I think its so your oil doesn't turn to sludge like they did with the old road draft tubes that didn't do their job in the first place. problem fixed though. It was my stupid push in breather. it was causing too much of a restriction and too high of a vacuum. Found a breather from my old i6(the old worn out one that had clouds of blowby and a busted up piston) behind my seat and popped it in, routed the hose to the top of the carb fitting where the hot air tube would have sucked air from(I got rid of all that for manual choke) and problem seems solved. no more smoke out the exhaust now. My big *** f350 box truck lugs so good up hills now and I don't look like a redneck with a diesel no more. Actually the smoke looked very white like anti freeze burning which is weird as heck. Threw a can of seafoam in my tank to clean up the oil in the intake as well because it was definitely sucking it up good from my pcv. Also going to replace that thing as well

 

Glad you got your problem fixed. I'm old enough to have seen clouds of smoke boil out from under cars and trucks at stop lights, all coming out the draft tube, caused by worn rings and such. I've owned cars that would burn your eyes at stop lights from the smoke coming out the draft tube.

Back in those days, every major traveled road had a black streak in the middle of each travel lane from oil blowing out the draft tubes.

The PCV valve made a big difference in both of those problems.

Again, I hope your problem is solved and good to hear it's running much better.

 

Thank you so much! Yeah it was weird and scared the crap out of me though. So much anxiety as this rig is really important. It is the only place I have to live. When I seen that smoke out of the tailpipe like that my stomach went into my toes. I need it to be able to go to work too as I am a contractor who lives on the road basically and I don't have money for a new one right now. Inside the box you can sleep and it has electricity with a bunch of lifepo4 batteries and servers for work and the top of the cab and box has solar on it and 5G wifi, tv....etc. One little china diesel heater keeps the whole thing warm. It's like those people that turn vans and crap into RVs but mine is utilitarian and not pretty but its more functional at least and ain't stuck at a shop paying through the nose when stuff breaks like them hahaha! I did what I had to due to the fact I have MS and can't always work so rent or mortgages are a big nope so contracts it is and when my body is tired and I can't do it I just can rest and go wherever I want.

 

Very true.
I used to show my students pics of highways of the '50s. Black stripes down every lane.
How any f us survived that in an age of bias ply tires, especially in the rain, is beyond me.