The Stovebolt Site Forums The Shop Area Engine Shop Retrofitted PCV System

Do these Retrofitted PCV Systems still exist?

I was interested in putting such a system in the Blue Funk. I read in Deve's about his idea of hooking up a gommet, PCV valve, hose, etc. in order to make your own PCV System. It sounded okay.

I think it was Hotrod Lincoln who critiqued the method of connecting the system directly into the block- you know- because of the chance of oil being sucked up into the system and such. I believe HRL suggested utilizing the old draft tube, cutting and blocking off the tube and inserting the fitting for the PCV System into the draft tube cylinder.

Then I thought, what the hey? Maybe somebody knows where I can locate an entire retrofitted system.

In the March/April issue of "Vintage Truck", there's an article on Crankcase Ventilation that talks about retrofit kits.

But maybe they're a thing of the past?

When I ran a shop in central California in the late 1970's, the Californicators in the state legislature decreed that all vehicles on the road, regardless of age, had to be retrofitted with a closed crankcase vent system. Several kits became available to block off the road draft tube, replace it with a PCV valve, and install an air inlet into the engine coming from the "clean" side of the air filter. For several years afterward, I installed many of those kits. Some were pretty generic, involving a lot of fabrication and adapting to individual vehicles, while others were either engine-specific, or at least they fit a particular general design of engine. The ones for stovebolt engines used a rubber 90-degree elbow that was attached to the road draft tube after it was cut off just above the oil pan rail, and a PCV valve was inserted into the elbow with a vacuum line running to the intake manifold. Fresh air was introduced into the engine by installing a 90 degree elbow over a hole drilled in the valve cover with sheet metal screws, and another nipple that was attached to the "clean" side of the air filter by cutting a hole under the nipple and attaching it with sheet metal screws. A piece of 5/8" heater hose connected the two nipples. If the engine had a vented oil filler cap, it was replaced with a sealed type. Any other vents, such as slots in the valve cover, had to be brazed or welded shut. At the time this was happening, cars had to be "smog checked" every year before license plates were renewed. Roadside emission testing was also done, similar to DUI checkpoints. When those procedures got too expensive to continue, the smog check was required only when a vehicle changed ownership, or a car was ticketed for emitting visual smoke. I haven't seen PCV conversion kits for sale anywhere in the past 25 years, and even back then, it was mostly a California thing, not nationwide.
Jerry

Thanks for the reply, Jerry. I copied a portion of your response here 'cause I've got a question...
According to Deve's method, if I remember correctly, fresh air enters the system through the vented filler cap or valve cover. The method you've described is more involved. What do you think about just allowing fresh air to enter the system through a vented oil cap? That's the way I was planning to do my setup.

It wasn't law in Texas, but we got tired of oil fumes making our eyes burn. We used to drill a hole in the top of the air cleaner and then weinstalled and EMT electrical conduit elbow and then did the same thing on the road draft tube and connected the two with heater hose. It didn't look pretty, but it kept the fumes out of the old cabs.

i have seen this type for V8

1955-1957 Chevy PCV Valve Conversion Kit

Item Number: 13282



Designed for 265 and 283 c.i. motors with factory draft tubes. A common complaint of 5-6-7 owners are fumes coming from the draft tube. The PCV kit is designed to route those fumes back into the motor and burn them.

Davey

If you are fortunate enough to have any, check your local junkyards. I just retrieved a PCV system off a truck during the last ODSS Junkyard Tour. I hope to have it installed before the trucking season.

crenwelge:
"EMT" is yet another acronym that is used in Auto Mechanics that has a reference in the Medical field. The letters stand for, of course in the Medical field, "Emergency Medical Technician". What does EMT stand for in relation to Auto Mechanics?
I often see the acronym "NOS" in these forums. What do the letters stand for? In the Medical field, the letters are used following a tentative preliminary diagnosis and stand for "Not Otherwise Specified".

svwilbur:
Cool! Is there any reason this kit couldn't be used on a 6 cylinder?

SWEET:
Yeah- I was hopin' to find an old Stovebolt with an old PCV system intact in a local junkyard. No go. It's good that you have found one and get to mess around with it.

EMT, from electrical not mechanics - Electro Metallic Tubing [conduit]
NOS as used here, New Old Stock [made back in the day, still on the shelf unused]
NOS as used by street racers, Nitrous Oxide System

Bill

I made my own setup similar to the one from Danchuk.
I used the PCV valve from a late 70s 250 camaro. It already had the right angle adapter on the PCV valve, so I didn't need the tubing elbow.
PCV Valve side of engine
Intake manifold side of engine.
No apparent problem with it sucking the oil out of the crankcase.

BTW -
EMT = Electrical Metallic Tubing
NOS = New Original Stock


regards,
Leon

There's nothing wrong with introducing fresh air through a vented filler cap or slots in the valve cover, but it wouldn't pass the Commiefornia smog law. The system had to be totally closed so a really bad case of blowby went down the carburetor throat, not out to the open atmosphere. That system also avoids introducing dust into the crankcase since the air comes into the engine after the air filter does its thing. In really dusty conditions, that does make a difference in engine life.
Jerry

Leon, I did the same thing on my 235 with parts from NAPA. Have your vacuum wipers suffered from the change? Because mine did and I switched back to the draft tube.

The wipers still work, but I haven't used them enough to really say whether or not there as been a performance hit.

regards,
Leon

Thanks for the clarification, Bill.

Jerry: Great information. Makes more sense to me now.

Nice looking setup you got there, Leon. Excellent pics. No problem with sucking oil, eh? Hmmm...

I'm in the process of gathering the parts needed in order to convet the Blue Funk to a PCV System.

I have a Road Draft Tube with the tube portion cut off. Surprisingly, I found a PCV Valve Grommet (HELP! #42313) that fits perfectly into the place where the tube was cut off. The Standard V178 PCV Valve sits snugly in the grommet.

I've got about 4 ft. of 3/8" fuel line hose to run it over to the intake manifold, where the wiper motor use to hook up. It seems that the old wiper port is on the small side in accepting the fuel hose.

Leon looks like he has a nice set-up with a replacement port.

Would it matter if I kept the old port?

I'm resubmitting this question:


The PCV Valve accepts a 3/8" fuel line and the size of intake manifold line is smaller. The "nut" on the intake port is a 7/8" with about a 5/8" openining.

I'm wondering if such a decrease in size, going down from a 3/8" to smaller, would present any problems in the PCV System?

Mine works fine. Im running 1/4. will go bigger later but I can feel some strong suction on the valve cover so I know it is pulling a lot out.

Thanks for your input, Grandpa's Truck.


Edit: What kind of PCV System are you running? Directly out of the block, or with some sort of extension? I'm wondering because of the amount of suction you're getting in your system. You know, sucking oil and such.

I guess the increased suction is partially due to that ventura effect thing.

Here is some pics of my PCV set up. I went to auto zone and just got a PCV valve with the spring in it. Grabbed a rubber gromit to fit and put it on. You will under stand after you see the photos. I got this Idea from a few other folks that had done it so I tryed it. I just popped the cap off my draft tube, then cut it down replaced the cap and drilled it out.

http://talk.classicparts.com/picture.php?albumid=180&pictureid=1523

http://talk.classicparts.com/picture.php?albumid=180&pictureid=1522

http://talk.classicparts.com/picture.php?albumid=180&pictureid=1521

http://talk.classicparts.com/picture.php?albumid=180&pictureid=1520

Nice setup. Thanks for the pics!

I've got my Retrofitted PCV System set up! It seems to work fine. I can feel some draw through the oil filler cap hole in the VC.

I've got another question.

Here's the situation: I've fit a grommet in the Road Draft cylinder where the tube was sawed off. There's about 1" left of the tube and the grommet/PCV Valve fit "okay". However, the grommet isn't as snug in the tube as I would like for it to be.

I've got a tie-down holding the grommet in the tube, but I want a more permanent solution. What do you suggest? Gasket Sealant, Silicone, or what?

Thanks.

Well not to sure. I eleminated the tube and just drilled a 15/16 hole in the top. But you can see if you can find a better fitting grommet at the autoparts store. Or weld in a plate and drill it out to the size you want.