Packard Forum Index » Modification Discussion

This is something I've wondered about for a while, and as I dream about my dream Packard and what I'll do with it, I often think of positive crankcase ventilation. (Yes, it is a kind of strange thing to dream about.) Has anyone done it with a Packard or other draft tube equipped car? Why or why not?

The "why" for me would be: less odor, less pollution, less noise and (some say) slightly better longevity for an engine that gets a fog of oily fumes through the carb.

In case you think I'm crazy to even think of this, the vintage Dodge/Plymouth site that I have used includes a "technical tips" standing entry with instructions for doing this mod on the Mopar flathead 6. Looks to me like just a little plumbing.

Plus, in the early days of PCV equipped cars, I remember reading claims that more pollutants come out of a draft tube than out of the exhaust.

So, "truth or dare" I guess. Anyone think it's truly a worthwhile idea, or ever dare to try it on a Packard V8?

In the mid to late 60's-early 70's certain parts of California required some pollution retrofits on some earlier cars. One was a PVC setup. Never saw one on a Packard so they may either have been too old by then or just not common or enough left in operation in those areas to see one yet.

As I recall, the retrofits on the cars consisted of either an oil filler cap with hose attached or the usual hole drilled in rocker cover. Some plumbing that went to the air filter where a hole was drilled and a plate with connection for the other end of hose was screwed on the side. I don't remember what if anything was specifically done to the draft tubes but they may have been blocked or restricted in some way.

It must have done some good but how much is debatable. When the engine was stopped, the blowby products really had nowhere to go except to condense. Not sure how detrimental that would be to an engine not designed for it. At least they didn't all go in the air right away which was the idea so maybe good overall.

Another retrofit was supposed to control oxides of nitrogen by installing some kind of vacuum control device which messed with the timing. That had to be done on a newer Pontiac I had brought into the state and caused lots of grief with performance, overheating, mileage and just about everything else.

Ihad a 55, 400 several years ago that had the pcv valve. I remember that one end was fitted into the crankcase breather and the tube going under the car was removed.
It was a rubber stopper with a tube attached to it. I don't remember were the other end went. I seem to recall that it went into a hole drilled into the intake manifold. I had a problem with this car. When I drove at speeds over 30 miles an hour, oil would blow out of the oil filler tube and coat the engine with oil. I could race the idle in neutral and see the oil come out the breather. This was a head scratcher and drove me nuts. The final resolution was to remove the pcv and and block the hole in the intake. That resolved the problem.

A PVC drastically reduced emissions and it also keeps the inside of the engine cleaner. Its a win-win.

Years ago, in the 70's, I had a 1951 Cavalier. It had the 327. I was always experimenting with something or other, on that car. I installed a PCV on it. I remember removing the road draft tube. Installing a cap with a hose connection over the stub end and ran the hose, with the PCV valve inline, to the power brake take off, through a tee.

I never experienced any driveability problems. But wound up removing it when an old Studebaker friend advised me that the carburetor was not jetted for something like that, And it might cause other problems.

Eric54, I believe your old Studebaker friend raised a valid issue. Installing a PCV on an engine not designed for it is akin to running with a vacuum leak. That, if not compensated for, would result in a lean fuel/air mixture which in turn would lead to poor engine performance and perhaps eventually to burned valves. Larger carburetor main jets would be a way of compensating for the altered (leaner) mixture.

I do not know if this is what you are looking for, but I had a 56 Clipper that had the downdraft tube plugged with a cork. The downdraft tube was tapped by the valley pan and a hose went to a oil recovery canister with a filter. Then from the canister another hose went to a plate that was between the manifold and the carburetor. I was told that it was to help your gas milage, on the theory that it would burn more of the vapors or something along those lines. It was also referred as an early PCV valve. I believe the unit was an oildex or something like that. It was a green canister. I can not find a picture of it, and the guy I sold the car to took it off.

I have installed a PCV setup on the engine for my '56 GH. I used a rubber grommet from a 1965-66 Buick 401 0r 425 valve cover, the one on the front left valve cover. I punched out the center to accept the PCV. I cut off the road draft tube and installed the grommet in the Packard valley cover, the other end of the hose goes to the vacuum connection on the rear of the carb.

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How many of you guy's who've added a PCV valve have sealed the oil filler tube? It won't work correctly if the oil fill cap is left original, as it's supposed to create a vacuum inside the crankcase. (which helps the rings seal better as well) One easy way to modify the oil filler tube is to take the oil filler tube from an Oldsmobile V8 and have it cut off and welded to the stock Packard fill tube, and use the stock Olds fill cap. This will help seal the motor like it was intended if it originally came with a PCV. Otherwise, adding a PCV without doing this is accomplishing nothing other than a vacuum leak.

Most modern V8 engines with a PCV system take clean air from a small filter located inside the carburetor air cleaner which is connected to the valve cover opposite the PCV. This is to remove condensate from the engine. Therefore the crankcase is not sealed.