A closed crankcase ventilation system. (Illustration from a November 1977 EPA publication; believed in the public domain in the United States)
Aaron Severson has brought a whole new level of thoroughly-researched in-depth coverage of automotive history to Curbside Classic. It has been an immense pleasure to have him sharing his research, insights and experience here, a number of time per week. It has elevated CC to a whole new level.
Although CC keeps Aaron quite busy, he has also been researching and writing diligently on the subject of early emmission controls and more specifically automotive engine crankcase ventilation and the environmental and political issues surrounding its adoption. After many months of work, this new article, “Science, Skullduggery, and Bad Faith: How the U.S. Auto Industry Adopted Positive Crankcase Ventilation” is now live at his site Ate Up With Motor. It’s a very significant historical document on a subject that has not received nearly enough airing.
It’s a fascinating detailed look both at the science of crankcase blowby, its effects on engine longevity but more important on its environmental impact. Contrary to popular myth, positive crankcase ventilation (“PCV”) had been around for decades before it was essentially forced on the auto manufacturers to reduce the toxic crankcase fumes that were being spewed by cars. The ad above is for a retrofit crankcase ventilator that was driven by a small electric blower. Note: This system was not designed to reduce emissions, as the fumes were still exhausted to the air, but it does show the awareness that PCV systems had a positive effect on engine longevity by reducing sludge and corrosive fumes.
Not surprisingly, there was a lot of obfuscation and foot-dragging by the manufacturers even though the science and technology was well understood. This would turn out to be just the opening salvo in the dragged-out battle between California and the US with the manufacturers over emission controls.
Speaking, Aaron’s pervious article at AUWM was “Before the Muskie Act: Early Emissions Law and Regulation, 1940-1969″. It’s another key part of Aaron bringing to light the issues, facts and political maneuverings in the early fight to deal with the rapidly growing issue of auto emissions. As a life-long Los Angelino, this subject has both a personal and historical interest to Aaron.
Links:
Before the Muskie Act: Early Emissions Law and Regulation, 1940–1969
I’m a huge enthusiast of P.C.V. valves, they really do prevent accumulation of sludge, assuming the operator does regular hot oil changes .
-Nate
Seeing Mr. Severson’s byline here has been quite a treat. Thank you for sharing this link.
I’m another PCV fan, my 1928 Chevy 1 Ton 4 cyl has a breather tube from the block to the Carb inlet, and the manual says not to use a vented oil cap unlike previous models, I’d say it’s a PCV system. The world war 2 Jeeps used a conventional PCV valve system. I think the early 50’s cab over Chevy 6 cyl’s also had PCV.
Yeah, that sounds like a simple air-cleaner-aspirated PCV system, like the one used on the Viking.
I’m enjoying these well-researched deep dives. Shout-out also to this examination of the supposed 1972 NHTSA exoneration of the 1960-63 Corvair (https://ateupwithmotor.com/model-histories/compact-economy-cars/reconsidering-the-1972-nhtsa-report-on-the-corvair), something I’ve long thought didn’t jibe with other evidence and test results, both those published in the early ’60s and those done more recently.
I wonder how many amps the electric motor of the Fram drew. The illustration doesn’t show any wiring, either.
The AUWM article is fascinating. I guess I knew there were different PCV systems in the Sixties, but not what the differences were or how they varied in effectiveness in reducing emissions. I already had my doubts about Cadillac’s Robert Templin because of his disdain for disc brakes, and it seems he was one of the bad actors in this story, too.
Ford not using PCV valves for a couple of years after the rest of the industry had gone along, kicking and screaming, seems particularly contemptible.
The ad text says the Fram crankcase ventilator fan was wired to the ignition circuit — you can see the wiring in the bottom illustration, coming out out of the bottom. No idea what its amperage was, but given that the motor and its housing look to have been about the size of a D battery, I’m guessing not very much.
Thank you for the link, Aaron’s articles are a real treasure!
I am hardly surprised by the reaction of the automotive industry: institutional resistance to any external (ie: regulatory) attempt to change how things were done, until they were forced kicking and screaming to do it
That was such a well researched and written piece, thank you!!
Imagine if the big 3 had been headquartered in Los Angeles. All the executives and engineers having to live in that smoggy ass hell hole every day. Im betting they would not have been quite so vehemently hostile to cleaning up emissions. Laws would still have to be passed but I think living with bad air every day would have been sufficiently motivating for the industry to do a bit of self regulation and try to clean up their act
In January 1954, all the members of the AMA Vehicle Combustion Products (VCP) committee went to Los Angeles for a three-week fact-finding trip on the smog problem. Chrysler’s Charles Heinen and Walter Fagley, who were part of that trip, later recalled:
Nevertheless, the VCP played a central role in the AMA’s strenuous and collusive efforts to prevent competition in emissions-related technology, deter regulatory action, and delay compliance with any emissions laws that were enacted. In 1969, Heinen had the temerity to stand up before the SAE and declare, “To date, medical research does not appear to indicate that much beyond what is being planned in the way of vehicle controls is called for in the forseeable future,” which should make anyone familiar with the state of urban air quality in the early ’70s shudder a bit: That’s what the industry thought was good enough and their having “done the job.”
I love how businessmen would use the medical research line for such things. Medical research hasn’t proven smog is dangerous. It hasn’t proven cigarettes are dangerous. Of course not since the health issues can take decades to appear and then still there will be quibbles about those long term studies.
What a remarkable treatise. Not for the first time with the car industry, if you want to choose between the conspiracy theory and the stuff-up, the reverse aphorism to the usual applies: choose the former!
I do not doubt for a moment that at Meta, at Twitter, at Google the self-same active deceptions are right now being enacted lest anyone dare regulate their evil ways – and their dominance, and profits.
And as the regulatory boot currently comes off the car industry’s throat, I’m sure they can be trusted to act well….
At some point in the past California required a PCV retrofit on all 1955 model year cars not factory equipped, enforced upon transfer of ownership. My 1957 Chevy had such a system. Smog check station just used a sheet of paper over the oil filler opening to validate function, as suction meant that it worked.
Yes, this program was a whole mess: California originally intended to require a retrofit for ALL 1955–1962 cars that didn’t originally have a PCV system as condition of registration renewal, not just on title transfer, but DMV managed to make the notices basically incomprehensible and then demanded that owners certify under penalty of perjury whether they’d complied with the requirement. People freaked out and started calling their representatives, so the Legislature backpedaled and made it only on transfer, while making it so noncompliance was an administrative violation rather than a maybe-go-to-jail crime.
Wonderful article. What type would the aircooled VW system be? Unfiltered air entered the crankcase via an opening, with oil baffle, around the crankshaft behind the pulley. A hose from the sealed oil filler cap area, that was an air-oil separator, carried fumes to the air cleaner. If one did not keep up with oil changes, or used non-detergent, the hose would fill with sludge.
I think that’s a Type III air-cleaner-aspirated system, the same kind of thing Soviet cars used.