Ditch That Pcv System Before It Is Too Late!

I go thru a roll of Bounty a week....
I use Bounty because they're " the quicker picker up'er"

 

Exactly.............How about Mr. Article Writer you do a leak down test on your worn out motor..........if your pressurizing the crankcase you need rings. What gets vented up through your breathers in your overhead and then recycled through the PVC chain should just be a minuscule fog of unspent combustion gases............and not enough oil to be worthy of a catch can......

We do run catch cans on the race car and also multi-stage dry-sump oiling systems whereby we create anywhere from 6-16 lbs of crankcase vacuum depending on whether the motor is naturally aspirated or supercharged............there are also 1-way check valves in the venting of the valve covers to the catch cans that are vented to atmosphere............on a normal run the cans will have a little bit oil in them unless you loose vacuum or torch a piston then a greater amount...........fuel contamination causing detonation for us is usually from the crankcase getting pressurized by combustion pressure leaking by rings and those same rings leaking that crankcase mixture back into the combustion chamber on the next cycle...................

 

I am going to be a different opinion. You can put one of these catch cans on a brand new factory Camaro, Challenger, Mustang or whatever and you will be totally shocked at what goes thru your motor in the 1st 2500 miles of a brand new engines. I was of the same opinion until I saw the results from several guys who installed them on engines with far less than 10,000 miles and was shocked. Engines today are nothing like engines from 20 years ago, especially when they put the controls on them like they do now days. A lot of what goes thru the engines is moisture mixed with the fog of oil and it really has nothing to do with blow by of rings.

 

"we create anywhere from 6-16 lbs of crankcase vacuum"

Do you actually mean pounds? Absolute vacuum is less than 15lbs under normal atmospheric pressure.

Yes, well... The M38A1 (F-head Jeep) also has such a system.

BUT as I understand it, during fording closing a manual valve actually provides pressure in the crankcase to keep water out of the crankcase and other critical spaces, via system of vent tubes. Plumbing PCV vacuum into them while underwater would make no sense.

 

Inches of vacuum........

 

I find this interesting! Never would guess that. I wonder if you can see the pulse of intake and the pistons traveling through the bores with proper test equipment located in crank case.

Never knew that was why the system was developed. Was always under the impression it showed up for SMOG reasons in the 60s. You learn something new everyday.

 

Not sure if anyone over here is aware of this tech memo from the day, but apparently it applies to both F134 and the Wagon/Truck L226. PCV for L-226 TSB 508

 

The corporate malware filter here blocks that site -

 

Apparently originally from 3b site: Engine Service Bulletins on CJ3B.info

 

The A1 system develops positive pressure. My 54 has only parts of the system, the early A1s (52-52) came with complete systems. My CJV-35 had a complete system on it and it pressurized engine, gear boxes and even the master cylinder. Pretty different design than a PCV.

 

Exactly. Although the idea of a sealed crankcase could apply either way.