331 / 365 / 390 CADILLAC PCV ADAPTER KIT

[charles in Dallas]

Greetings,
I just bought a 365 and the draft road tube is missing!
I found this kit, but it is not made anymore, anybody know of something like this? Seems like a good idea, better for the planet and less fumes when the car is not driving.
https://www.jalopyjournal.com/forum/threads/331-365-390-cadillac-pcv-adapter-kit.1229304/
- Charles

[R S Steven]

HI Charles,
Click on the link below and read Jim Eccleston post.  I followed the steps and added a PVC system to my 59.  It works great. I picked up most of the parts on ebay.

http://forums.cadillaclasalleclub.org/index.php?topic=85049.msg85049#msg85049

Cheers,
Bob

[5390john]

I installed a PCV system in my '55 CDV with a stock 331, my understanding is that the 365 would be basically the same installation.
See attached info, you will need the PCV tube fitting (junkyard item) that fits in the valley cover that replaces the draft tube. You connect the PCV valve to the rubber hose from the tube, and the rubber hose from the PCV valve to a spacer under the carb.
You can get a spacer from Dashman's Hot Rod and Speed Parts www.dashman.net  They have a large selection, I would call them, they are very helpful. I bought a spacer from them and installed a brass tube in the spacer to connect to the PCV valve.
I would VERY STRONGLY suggest viewing www.mewagner.com to research proper PCV theory, function and installation of a PCV system. I talked to them at length and installed one of their PCV valves. WORKS PERFECT!!!!!!!
Also a good idea to install intake manifold gaskets that block off the heat riser passages in the intake manifold. Olson's gaskets makes them.
After a LOT of trial and error, I finally came up with a properly functioning system that was a "clean and sanitary" install.
Hope this helps!
John Adams

[PHIL WHYTE CLC 14192]

This is probably a stupid question but what improvement does a PCV valve give a 50s engine. I know very little about them but am I right in thinking that it replaces the engine breather tube and directs the breather back into the inlet manifold?

[The Tassie Devil(le)]

No real benefit, apart from getting rid of the fumes exiting out the draft tube, and passing it through the induction system, and out through the exhaust pipe.

The proper thing to do is to complete the system by running the crankcase breather intake to come from the clean air that is passing through the air cleaner that sits atop the Carburetor, which means closing off the Oil Filler Cap as a source of air intake. 

Bruce.

[James Landi]

Phil,

Adding a bit to Bruce's comment, I owned two '56 Cadillacs --- both had fabulous A/C, but at traffic lights during hot weather, noxious blowby fumes entered the cabin. Any simple passive vacuum from the engine intake massively improves the "living conditions" in the cabin.  The blow by is inevitable, and as these engines wear, the fumes increase.  My cure was hardly elegant--- just a simple 1/8 metal tube drilled into the oil cap and a "tee" into the intake manifold  VOILA, poison smoke gone, and by the way, that metal tube collected a gray mass of moisture and oil.  yuck.   James

[PHIL WHYTE CLC 14192]

Thanks guys. Phil

[fishnjim]

Those of you old enough to recall the evolution of the factory PCV systems, will know that it was not straight forward as plunking in a PCV valve.   There were all sorts of air cleaner breathers and filters used to prevent "gunk" getting into the carb and the PCVs themselves failed/plugged occasionally with "gunk".   The fix was to replace frequently during  tune-ups.  Position of the pickup also changed, some on the valve cover, etc.  The crankcase vent pipe common to these motors is merely convenient.   Some connections into the air cleaner were outside the air cleaner filter some were inside.   The problems are, as Landi noted, condensation and oil vapors.   There's no gas/liquid separation space in the small vent.   Combustion produces water vapor so must be vented if not all going out with the exhaust.
If an old motor is blowing by that much, it's past time for a overhaul.   
I don't have any problem with PCVs, just want everyone to realize they're not a panacea for a poorly functioning engine.   These were an early EPA mandate to reduce crankcase hydrocarbon emissions for smog control which is noble.  {Watch Johnny Carson reruns from the '70s and listen for his CA smog jokes.}   These things took many iterations to become error free.   With the advent of the catalytic, they can burn a lot more of the fugitive hydrocarbons and not pollute.  These cars are not equipped.   So expect some tailpipe emissions, maybe plug fouling, etc. if you live in a area that requires emissions tests, if not exempt.   All those improvements, HEI, platinum plugs, etc were linked in the effort to combat vehicle emissions.   
That's the basis of the push for EVs, but that's a partial and costly solution as the electricity mostly comes from power plants which burn fuels.   There's not enough solar capacity to fully service the vehicle markets.   Like most of these poltical solutions, not well thought out.   The numbers of cars on the road has made it to the point where they're producing a volume of exhaust equal to the amount of air were breathing.   So there's effort to curb tailpipe CO2 looming which has no solution.
The climate has not "changed", the number of people and what they do/energy they consume has changed/increased dramatically.   The life span has increased also, so more are doing more longer creating issues...

[The Tassie Devil(le)]

.... My cure was hardly elegant--- just a simple 1/8 metal tube drilled into the oil cap and a "tee" into the intake manifold  VOILA, poison smoke gone, and by the way, that metal tube collected a gray mass of moisture and oil.  yuck.   James

The big problem with doing that is that there is the possibility of sucking really dirty air back up through the draft tube, and into the crankcase, which is especially worse when driving on a dirt road or dusty conditions.

Plus, the major problem with the Draft Tube was that oil droplets can escape and fall onto the road surface creating further problems.   The old days with mostly dirt and un-sealed roads, that wasn't an issue.

Bruce.

[5390john]

The primary benefit of a properly functioning PCV system is lower engine emissions. Secondary benefits include a dramatically cleaner internal engine (the engine has constant ventilation from the intake manifold vacuum draw that does not exist with a road draft tube) which results in longer oil change intervals due to much cleaner engine oil. Another benefit is that internal sludge buildup is dramatically reduced.
The PDF I attached with my previous post is the ONLY authoritative and researched information I came across, backed up with direct contact of a knowledgeable person to help me get a system that really works.

BTW, despite all the skepticism I have seen on this forum regarding EV and infrastructure to support it, I follow this stuff fairly closely and I think the transition will go much more smoothly than most people think. Clean energy sources are coming on line much faster and in greater capacity than even the most recent projections.

I also think that restoring classic cars as a hobby is going to come into a new golden age as GM's new eCrate motors and systems become available for retrofit. This is also true for high performance vehicles as even the least expensive vehicles will offer supercar performance.

2, maybe 3 cents worth of opinion!!
John Adams