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What do you need and how do you install the EPA valve and where exactly do you connect the appropriate hose and fittings, to delete the oil breather tube from the rear of the engine block. The vapors become overwheleming when hot.
Its the PCV valve (Positive Crankcase Ventilation) system...
You will need a PCV valve, a right hand spark plug loom from a 63 car (repros are around) to hold the plug wires when the road draft tube is removed, a vented oil filler cap and a means to convert the road draft tube to support a pipe or hose attachment. You will also need the rear base of the carb drilled to accept the brass fitting.
Search for RPO-242 on here and/or refer to your AIM (Assembly Instruction Manual). If you can't find the crankcase hole conversion fitting shown (expensive but Paragon had them) a grommet with a hole as used in 63 works just as well.
Last edited by Frankie the Fink; 08-09-2017 at 02:44 PM.
I am working on an article about PCV valves which I hope to have completed soon.
Here are a couple of pictures of a way to eliminate the draft tube and install a PCV system.
Joe
Here is the adapter that Frankie is talking about attached to the back of the engine.
This where it connects to the back of the carburetor. The PCV valve in the picture is a Standard Ignition V-112 which fits many 60's and 70' GM V-8's.
One side is 3/8" and the other is 1/2". Note, do not use fuel line as it will soften over time. For the 3/8" side I use power steering return line, also great for power booster lines, and 1/2" emission hose.
Another way to do it would be to use a V-100 Standard, 6421934, CV590C valve that you can thread directly into a street ell off the back of the carburetor eliminating the 3/8" hose.
A 1961 PCV system can't be called an "EPA System" as the EPA wasn't founded until 1970.
Thinking the California Air Resouces Board might have been the instigator to using the valve on all new California cars in 1961, I looked it up and CARB didn't come into existence until 1967.
Something I had forgotten about. New York made it mandatory on all new vehicles in 1964.
A further point, all US manufacturers voluntarily installed the valve starting in 1963 so it looks like the FEDS had nothing at all to do with this feature.
A further point, all US manufacturers voluntarily installed the valve starting in 1963 so it looks like the FEDS had nothing at all to do with this feature.
The PCV system was much better at removing water vapor and corrosive compounds from the crankcase and oil, than the road draft tube, it helped with engine longevity, and probably also helped make warranties of 12 months and 12,000 miles possible compared to the 3 mo/3,000 miles that were typical of 1960.
The PCV system was much better at removing water vapor and corrosive compounds from the crankcase and oil, than the road draft tube, it helped with engine longevity, and probably also helped make warranties of 12 months and 12,000 miles possible compared to the 3 mo/3,000 miles that were typical of 1960.
Doug
That is one of the best features ever added to the IC engine.
I can remember in 1963, the word was going around the smart thing to do was to unhook them and put the draft tube back on as the PCV was costing power.
That is one of the best features ever added to the IC engine.
I can remember in 1963, the word was going around the smart thing to do was to unhook them and put the draft tube back on as the PCV was costing power.
I've owned and worked on flat head and overhead engines with the road draft tube set-up, and the PCV makes for a much cleaner and happier engine. Unbelievable how much crud was in some of those engines at teardown, even the maintained ones. PCV is a good thing!
Unbelievable how much crud was in some of those engines at teardown, even the maintained ones. PCV is a good thing!
I can remember pulling valve covers that were almost completely filled with sludge. Just enough room left for the rockers to rocker. Oil pans that you could scoop the sludge out with your hand. Rocker valleys full of it. Used to have to take the oil separator can out (after you dug for it) and set fire to it to burn the sludge out of it.
This, even with detergent oils of the time but still lacking some of the additives that prevented sludge.
Did I mention rod/main and cam bearings pitted and eaten by corrosion as well. Don't see much of this anymore at all.
...I can remember pulling valve covers that were almost completely filled with sludge. Just enough room left for the rockers to rocker. Oil pans that you could scoop the sludge out with your hand..
Cadillac's maintenance regimen in pre-PCV days was to annually pull the oil pan & clean it out.
Look at old photographs of roadways with the black stripe down the middle of both lanes. I agree, draft tubes were the automotive equivalent of piping raw sewage into rivers. Out of sight - out of mind, until it isn't.
Cars with draft tubes can stink, especially among tired engines with copious blow-by. Some manufacturers employed a breathable cap filled with steel wool, much like a valve cover breather on the road end of the draft tube to mitigate this but it was tantamount to pissing through a screen door.
Any motorcycle rider in bygone eras remembers when they were told to avoid the middle of the lane...that was where all the road draft goo would get sprayed down and when it rained that greasy stuff would rise up and be dangerous to ride across...
Any motorcycle rider in bygone eras remembers when they were told to avoid the middle of the lane...that was where all the road draft goo would get sprayed down and when it rained that greasy stuff would rise up and be dangerous to ride across...
Yep! My '47 Chrysler Highlander had a serious blow-by issue and it would blow oil smoke out of the bottom of the draft tube like a freight train. Right about dead-center of the car. I knew and old guy at a long-ago junkyard who had a flathead powered 'yard car' that had so much blowby that he had a little tin cup hanging under the road draft tube. I was talking to him one day, with it sitting there idling and sounding like it was swapping rods, puffing away, and he casually lifted the little cup off of its hook, removed the breather cap, and poured the oil right back into the engine....an 80 year old guy with a cigarette hanging out of his mouth. He ended up passing away and that yard car was still running.....puffing and belching away....
Yep! My '47 Chrysler Highlander had a serious blow-by issue and it would blow oil smoke out of the bottom of the draft tube like a freight train. Right about dead-center of the car. I knew and old guy at a long-ago junkyard who had a flathead powered 'yard car' that had so much blowby that he had a little tin cup hanging under the road draft tube. I was talking to him one day, with it sitting there idling and sounding like it was swapping rods, puffing away, and he casually lifted the little cup off of its hook, removed the breather cap, and poured the oil right back into the engine....an 80 year old guy with a cigarette hanging out of his mouth. He ended up passing away and that yard car was still running.....puffing and belching away....
I had a similar deal on one of my little red cars that had 250,000 miles on it. I recoverd the blowby oil the same way. If you didn't dump the oi on a timely basis, the excess would collect in the hose to the air cleaner and then when you nailed the gas pedal, the smoke would roll out the back like a crop duster.l
Any motorcycle rider in bygone eras remembers when they were told to avoid the middle of the lane...that was where all the road draft goo would get sprayed down and when it rained that greasy stuff would rise up and be dangerous to ride across...
Still applies due to cars that have oil leaks.
Doug
08-09-2017, 01:08 PM
EPA system for 1961 vette Oil vapor smell
