VCCA Home Forums TECHNICAL - 1945 AND NEWER 1961-1964 '62 PCV setup

The '62 Biscayne I bought this spring has some blowby. I ran some top engine cleaner through it which helped but it still marks it's spot on the garage floor from the draft tube. I've been told I can retro fit a newer PCV set up to my '62 283. What parts do I need in order to do that? Thanks.

Tiny,
PCV system was offered as an accessory in 62, mostly for heavy service use (cabs, police cars). It was pretty much the same one used as standard equipment on the 63. The breather cap is the key piece to the changeover. If you use the regular 62 cap you will have one heck of a vacuum leak. I have to look but I am pretty sure I have everything but the cap.

The 1963 was the first to have a PCV. (except Ca.)
If you find a 1963-1967 in a junk yard you could remove the parts.
Bascially you would need the adaptor that fits into the opening your draft tube is in. Fitting for back of carburetor (I think that is where it was located), the hose betweent hose two and a PC valve.
The carb. on a 1963 was a bit richer to make up for the vacuum lost to the PCV.
I should be able to find a pictur/text for you.
It can't handle an excessive amount of blow-by.
If it were my car I would remove the intake manifold and replace the breather can.

Breather can?? You'll need to educate me Gene. Tell me what you have and shoot me a price John. If I don't have to mortgage the house we might do business.

The can is under the intake manifold at the rear of the lifter valley. It goes into a passage at the rear of the block, the passage goes up to the top of the block. It exits to the rear of the distributor and a road draft tube goes into it or a fitting with a hose nipple on it that has a pic valve in it and then to the rear of the carb.

The "can" has baffles in it so the fumes pass out but the oil doesn't. They are often plugged with sludge. We used to just replace them rather than cleaning. I would bet new ones are still available.
You might be shocked to see how much sludge is under the intake manifold and laying in the V.
I looked at the advanced 1963 features and the 1963 shop manual supplement and neither have pictures or a better description of the PV system.

No mortgage needed for that stuff, finding it is the problem. I will try to scan my 62 accessory manual and it really has some great detailed diagrams of the entire system. I got some things to do now and it is getting late. There is a metal "elbow" that goes in place of the breather tube. The PCV valve is a straight metal (solid little thing) that goes in line.
I think Genes answer is best I would get that intake off and you will see a round can held in by a slot head 1/4 20 screw that is all clogged up. I know I have one on the shelf I can send you a picture of. If you are dumping that much oil out of the tube a PCV is only going to give you other problems. Is the breather cap all clogged up?

Just to add or eleminate confusion there are two different types of PV systems.
The 1963-67 used the open system. It pulled outside air in through the oiled mesh oil filler cap. Chance of some dust entering.
In 1968 it was changed to a closed system. The oil filler had a "solid" cap and the air entered through the air filter. Has its own little filter that fit inside of the air filter. The fumes were pulled out from the top of the right valve cover and into (or throught) the PV valve and burnt. Problem with this system is when the blow-by got excessive the oil backed-up into the air cleaner and damaged the paper regular air filter element.
The system was used prior to 1968 on some applications. The closed system was more of a government required thing required for 1968.

OK, so I need to pull the manifold to access the can. I'm assuming they are available through normal parts stores? It's called a 'breather can'?

As far as I know it is only a GM part. It can be soaked and cleaned out. It is called a "Ventilator" group #1.745 part number 3728502 all the same from 55-66 (my parts book only goes to 1966) all small block. But it sounds like your engine is pretty gunked up inside, I would just get an intake gasket set and take it from there. Thinking about it there is some negitive pressure going on in order to force oil out of the breather tube. I would look at the oil fill cap and make sure that is clear, spray it with some brake clean. I have seen some all crudded up it almost almost looks like ashphalt. Combine that with some wear on the cylinder walls (seems like every good running carburated small block I ever tore down still needed to go 30 over after 70,000 miles, and you would never think it they way they ran before tear down) also forcing a lot of air into the crankcase. It has to go somewhere, and like electricity it will seek the path of least resistance. In this case the breather pipe. If the cap was all crudded up after you clean it place an old sock over the cap while you are running it, it will help catch any oil mist that might (no it will) spray fine mist of oil out of the newly cleaned brather cap, thus driven by the fan getting all over your engine compartment. Start with the breather cap fist, easiest and cheapest fix which is allways a good place to start for me.
I installed PCV system on my Biscayne in my quest to "load it up" with correct accessories. Something was wrong, seemed like a huge vacuum leak so I removed the system. My engine was rebuilt and I was not looking to correct any problems like you are now. I did notice that there is a different cap listed group #1.758 and the part # for the normal cap is 1552233 and the cap listed for a closed system is 3714983. I suspected that the cap was the culprit to the problems I had, but I was in a hurry to finish the car for Grand Junction and I never bothered to research it any further. My 62 Accessories manual is in a bag with books for any needed documentation when the car gets judged. I keep it in the trunk of the 62 which is in the trailer. I have a busy day ahead of me today so I don't think I will be able to get to the books until later today

Thanks John, I'll start with the breather cap.

Tiny, What I will suggest is first remove one valve covers to see how badly the engine is sludged-up.
Even though there was detergent oils when the car was new unless you changed the oil every 1000 miles or so the engine will fill with sludge. Especially a car driven on short trips and not getting the oil Hot. Pick the easiest to remove cover or the one that looks as if it could be leaking. Place some cardboard under the engine incase the oil return holes in the head are plugged up and the valve covers full of oil.

OK, Gene, sounds like a plan. Anything that requires extended bending or lifting will have to wait. I've been down in the back for weeks. It seems like just pulling my pants on strains it. I know the cause. As a big strapping lad I suffered extensively with "strong back, weak mind" syndrome. Now I'm paying for it.

Clogged oil return holes in the heads are not going to force oil out of the breather pipe. The problem is caused from to much crankcase air pressure either caused by excessive piston blow by or clogged ventilation, my guess it is a combination of both, but nothing to do with return oil flow. That causes a total different set of problems.
Tiny hope you feel better

I know that the clogged holes will not cause blow-by and dripping but it will be a good indication of the sludge content of the engine. I would be willing to bet that this is a heavly sludged engine.

John,
According to the '62 AIM, the optional PCV system used the same open type filler tube cap as a system with a road draft tube. If manifold vacuum is pulling crankcase fumes out, through a PCV valve and back into the combustion chambers, there needs to be a source for clean air to enter the crankcase to replace the air that's being pulled out.
If the car has enough blow-by pressure (more than the intake vacuum can pull through the PCV valve), then the blow-by will exit from the oil filler tube.
CCV (closed crankcase ventilation) is another story. In that case, no crankcase vapors can escape to the atmosphere due to a tight fitting cap on the oil filler tube and a side tube that routes to the underside of the air cleaner. With that system, whether the crankcase fumes are all pulled through the PCV valve or backed up out of the oil filler tube, they all enter the intake manifold and are sent to the combustion chambers.

Verne

Hey Verne,
That is what I thought, but I still have not had time to go out to the trailer and open it up to get the book. With Drs appts and such to get out of the way before I head down to my house in Florida on Saturday, glad you checked yours.

I had the open cap on mine just like the book had shown and it ran like crap with the PCV system installed. I used an NOS PCV from a 63 I had which was listed as the same. Everything in the engine was new and rebuilt, and it was about my 30th small block that I had done so I was confident it was not internal. I think it could have been a vacuum leak at the nipple at the rear of the block, or the PCV could have even been bad out of the box I never researched it any further as to why, all I knew it was running good after it was out. It was one of those thing that just was not that important to me at the time. I was more concerned about getting to run right, I was pressed to get the car done after 15 years, and I was also co-chairing the VCCA 45th Anniversary meet in Colorado, besides a huge project I had to finish at work at the time. So I was happy the problem was resolved and sort of forgot about it.

Over the years I only came across one 62 and one 60 with a PCV set-up. Both were in a junk-yard outside of Newburgh NY the 62 was used for Dept of Water Car and the 60 was a used NYC Taxi,(cowl tag even read for the paint "NYC TAXI") both were 283's, the 62 had overdrive which you seldom ever saw. Looking back on it now I think it could have been a vacuum leak at the 90 degree elbow that goes in place of the breather pipe, but at the time I was not excited about spraying brake clean all around the engine bay of a freshly restored car. I kdid notice that there is a different breather cap listed in 64, not for 63 that uses the same open element cap as the earleir years where it was optional.

My concern is that if a later style system is installed with the open cap it might not work as planned. Either way I would bet Tiny's breahter cap is not breathing to well if at all.

I ran into one of those PCV valves installed backwards. Don

Don,
that was the first thing I checked, I sure was trying to avoid pulling the distributor out. Again I wish I had more time when I was looking at it

With the closed system the oil will back-up in the air cleaner if blow-by is excessive. The PC system can handle only a limited amount of blow-by.

I'm a little confused, the PCV system that uses the air cleaner for air ventilation was a later system unlike the 63 and earlier that we were(?) talking about.

The discussion (I guess) was about an open vs a closed system.
My 1962 info states option # 242.,
Special crankcase vent. system California type and
option 417, positive type crankcase ventilation system. The positive would probably been the closed type.....do you have a picture of that?

RPO 417 was a closed system and was only installed on the 6cyl engine. They actually cut a hole in the side of the valve cover for a fitting and hose to the air cleaner base for the clean air input. The oil cap on top of the valve cover was a closed cap, rather than a breather style. The PCV was installed in another hole in the top of the valve cover.

By the way John, I've been running the PVC system on my '62 '09 for many years and after a long ride I get an oil slimed filler tube too. Of course, the engine is a very worn standard bore. I just put a sock over the filler tube to cut down on the mess.

Verne

Gene Yes I can get the pictures of (drawings) of both. I have to go to my mother-in laws house today anyway, that is where I keep my trailer with my 62 inside of it. She is 95 and still lives by herself, and is in great shape. As I said in an earlier post I keep all of my books that I might need for any documnetation on the car if asked in a bag in the trunk. I have to see her later today and so I will get them out, and with the (much needed) help from one of my son's I will post the pictures/scans. I remember there were some very good drawings in the assembly manual as well as the AIM.
I think maybe the RPO 417 was California only? just because the 242 was available in all engines and the six as well. It is just odd that RPO 417 is six cylinder only, as I recall that set-up looked like it was almost made of of spare parts in a high school engineering class.

Verne, did you add that on or did come with it?

Later this afternoon after the Yankees game I will have some pictures from both books

Not wanting to beat a dead horse but I've been thinking about the issue. While the '62 has a bit of blowby it's not really bad. After shutting it off after a drive I'll see a wisp or two out of the breather cap but that's all. I once had a Y block Ford as a kid that had so much blowby I'd fog the neighborhood for mosquitoes every time I shut it off and it never left the oil underneath that the '62 does. Would a plugged breather can cause the drip under the draft tube? Since I'll go ahead and clean the cap but it's not totally plugged or I wouldn't see the wisps I do.