PCV delete ideas/vent with catch can

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805moparkid

805moparkid

Slant and AFX Guy
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i want to delete my PCV on my 6 cuz i think its sucking up oil at high rpm....

what do you guys have? just another breather or those catch cans with steel wool in them?

thx
 
check to make sure the breather is not clogged up and the baffle inside the valve cover is not missing or sludged up,removing the pcv will cause a rich condition and fuel mileage will suffer
 
waggin said:
check to make sure the breather is not clogged up and the baffle inside the valve cover is not missing or sludged up,removing the pcv will cause a rich condition and fuel mileage will suffer
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the breather is clean, sprayd out with brake clean
there is the baffle under the pcv and breather

i can rejet the carb to fix the rich condition...

i stuck a valve after going to the track and the intake ports had a bunch of oil in them (intake and intake ports) so im thinking the pcv is to blame...

its a hot 225 with a 600 holley on it...
 

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I would not blame the PCV .......SYSTEM

It's possible that you have blowby from something...valve guides, maybe, that is causing a lot of oil to be "in the air", other things like oil overpressure, loose bearing tolerances, etc etc,

but I would not toss the PCV

One thing you can try is find a breather off a late 60's --70's Ford product. It will fit in place of the twist in cap on your valve cover, and is made for a pcv valve to be installed on top. this would give you an extra layor of breather material and "drain back." Of course then you'd plug the original valve cover opening.

Here's a picture. As I remember, the fat part of a PCV should fit the grommet.

mump_0909_05_+1970_ford_mustang_boss_302+engine_view.jpg
 
Kid, Slant six Dan ( I think) had a fix for this using a baffled breather from a GM ( Buick Olds etc.) that works and you install your pcv valve in the top of it like the Ford above but is a push in where the pcv is now. Maybe do a search on SS.org . If not when I go to my shop I can look for the part# for you....
 
The PCV system is nothing more than early emissions. Its purpose is to reburn crankcase vapors instead of venting them into the atmosphere like the old OCV (Open crankcase Ventilation) used to do. If you eliminate the PCV, you will need to readjust the carburetor's air fuel ratio, but other than that, there won't be any negative results. Some use the arguement that the PCV system aids in ring sealing, but this isn't true. As long as there is no pressure in the crankcase, the rings seal fine. When PCV valves become clogged and positive pressure is put into the crankcase because of crankcase vapors building up, then the rings seal can be effected. In other words, a clogged PCV valve will aid in the rings leaking. The old OCV systems rarely ever clogged, because the valve cover was vented with a LARGE pipe. Some of the older Fords like the Rustang and Falcon had OCV pipes coming right out of the side of the BLOCK. I had a 64 and 65 Falcon both with the 170 six and that's how they were vented from the factory. Read about the PCV system and it's origins here:

http://en.wikipedia.org/wiki/Crankcase_ventilation_system

As you can see, it all actually came about because tanks and other equipment needed a closed system to keep water from entering during fording.
 
805moparkid said:
i want to delete my PCV on my 6 cuz i think its sucking up oil at high rpm...
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Do you also want to shove a cork in your tailpipe because the engine smokes? Don't be halfaѕѕed. Find and fix the problem. If your PCV system is actually sucking oil into the intake tract, then it means something's wrong. You're missing baffles or your breather is toast or there's another problem. What exactly leads you to believe your PCV system is sucking oil at high (or any other) RPM?
 
StrokerScamp said:
If you eliminate the PCV, you will need to readjust the carburetor's air fuel ratio, but other than that, there won't be any negative results.
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That's not correct. The engine oil will get much dirtier much more quickly, and so will the crankcase itself. PCV is all benefit, no drawback.
 
i'm gonna have to side with ssdan on that, oil aint gittin no cheaper and it sounds more like something ailing in the valve seals or the guides, jmo
 
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I have had some headaches with my old six along these same lines.

There was actually a kit, (an old one), to change over from the open crankcase vent to a closed system.

Several of the street racers around here set up a vacuum system so as to always have a negative pressure in the crankcase.

I had an idea that I have not followed up on yet.................

There are old school / old type fuel pumps that have a vacuum pump stacked on them as an assembly.

They were for suppling the vacuum for the early windshield wiper systems.

With some work I may be able to use one of those to help with my problems.

More modern engines like you guys use, may see a benefit from drawing vacuum on the crankcase in order to improve things.

Worth looking into.
.
 
StrokerScamp said:
The PCV system is nothing more than early emissions. Its purpose is to reburn crankcase vapors instead of venting them into the atmosphere like the old OCV (Open crankcase Ventilation) used to do. If you eliminate the PCV, you will need to readjust the carburetor's air fuel ratio, but other than that, there won't be any negative results. Some use the arguement that the PCV system aids in ring sealing, but this isn't true. As long as there is no pressure in the crankcase, the rings seal fine. When PCV valves become clogged and positive pressure is put into the crankcase because of crankcase vapors building up, then the rings seal can be effected. In other words, a clogged PCV valve will aid in the rings leaking. The old OCV systems rarely ever clogged, because the valve cover was vented with a LARGE pipe. Some of the older Fords like the Rustang and Falcon had OCV pipes coming right out of the side of the BLOCK. I had a 64 and 65 Falcon both with the 170 six and that's how they were vented from the factory. Read about the PCV system and it's origins here:

http://en.wikipedia.org/wiki/Crankcase_ventilation_system

As you can see, it all actually came about because tanks and other equipment needed a closed system to keep water from entering during fording.
Click to expand...
I have been looking for someone to say you don't need to run a pcv System. A mechanic took mine out of my 318 and said I don't need it. ( I have a breather on each side) He also built and races a 9 second car so I Figured he knows what he is doing. He's been working on cars for 35 years or better.
 
Drag cars use a scavenging system whereas they install an agled bung into the headers and is basicly siphons the emissions from the crankcase....it works well at full throttle......pcv system was intended for street use.....
Dustedu2 said:
I have been looking for someone to say you don't need to run a pcv System. A mechanic took mine out of my 318 and said I don't need it. ( I have a breather on each side) He also built and races a 9 second car so I Figured he knows what he is doing. He's been working on cars for 35 years or better.
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Dustedu2 said:
A mechanic took mine out of my 318 and said I don't need it. ( I have a breather on each side) He also built and races a 9 second car
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Uh-huh. This 318 car of yours, is it a 9-second car? Is it a race car at all?

If not, what your mechanic did was dumb.
 
sometimes an engine will need a modification to go with another modification. It is always best to locate a problem and correct it rather than applying a band aid. for instance lets say you street drive the car more than you race it and suddenly it develops a rear seal leakage problem.......(and that's a big problem) you can contribute the failure of that rear seal to the fact that you eliminated the vacume that was engineered to keep that rear seal from leaking......I rest my case :grommit:
 
slantsixdan said:
That's not correct. The engine oil will get much dirtier much more quickly, and so will the crankcase itself. PCV is all benefit, no drawback.
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Ok. I'll take your word for it. Everything I've ever read or experienced says otherwise.....cause Lord knows I ain't the only knife in the drawer...and sure as hell ain't the sharpest. LOL
 
waggin said:
sometimes an engine will need a modification to go with another modification. It is always best to locate a problem and correct it rather than applying a band aid. for instance lets say you street drive the car more than you race it and suddenly it develops a rear seal leakage problem.......(and that's a big problem) you can contribute the failure of that rear seal to the fact that you eliminated the vacume that was engineered to keep that rear seal from leaking......I rest my case :grommit:
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...and all that makes sense. Even from the article I posted it even said that those older engines with OCV seaped oil from many places. So with that reasoning, there's probably some truth there. I suppose as with everyhting else, everything improves with time. Well...almost everything. lol
 
I'm certainly not a fan of "breathers only." For one thing, millions and millions of on the road vehicles have been running PCV now for what, since 62 or 3?

I'm old enough to remember "road draft tubes" and how some of "our stuff" leaked big time FROM that road draft tube. But you NEEDED a road draft to help build a draft through the engine, and on many of those sloppy old girls, they STILL puked oil out the top breather.

BUT I've known some guys with newer engines (no road draft) who ran "breathers only." Guess what? The cab stunk. It smelled. Like OIL. That's because SOME oil mist was coming right out those breathers and back on the firewall.

I say fix the engine, and keep the PCV. In the meantime, you MAY well need to engineer some sort of auxiliary catch/ drain/ breather can to help the PCV along.
 
well what happened is when i had to pull the head off because of sticking a guide (exh), there was more than normal oil behind the intake valves, and the only the intakes...

so when i checked the intake manifold there was oil in the runners...

so knowing that the PCV valve and hose are new and unclogged, (working towards carb, not into crank case), i deduced i was getting to much oil in thru the pcv system...

i have done oiling mods and have been spinning it to 5800 @ the track so i figured the oil was getting around the factory baffle and getting sucked in...

hope this helps you evaluate my situation guys...

thx ed

and im not running that god awful ford air cleaner...
 
Ed, some of wehat you're experiencing might be normal for racing duty useage. I could be wrong. you might consider one of those evacuation hose and tube setups goin into the header from the valve cover.
 
StrokerScamp said:
Ed, some of wehat you're experiencing might be normal for racing duty useage. I could be wrong. you might consider one of those evacuation hose and tube setups goin into the header from the valve cover.
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that kind of what i was thinking but like said its only good for top end... maybe after they fix the guides (exh)... again it will chill out... doubt it tho...

easy thing would be a vacuum pump but i cant even afford axles right now...
 
Since an engine only delivers vacuum to the PCV valve at idle and part throttle (at wide open throttle you have no vacuum) I can't see how the PCV could possibly cause your problem. Sounds to me like it's sucking oil through the intake valve guides.
 
fishy68 said:
Since an engine only delivers vacuum to the PCV valve at idle and part throttle (at wide open throttle you have no vacuum) I can't see how the PCV could possibly cause your problem. Sounds to me like it's sucking oil through the intake valve guides.
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well thy were just done using hardened steel guides set to .002 (two weeks ago), and these guys hand hone each guide...

think you see my confusion lol...

its acting like a wore out engine but its new!
 
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