Noticing some smoke coming from valve cover breather on 67 Satellite with a 360 engine. Am I missing something obvious?

[tonyp25]

So the car is new to me and the supposedly the engine was rebuilt recently with less than a few hundred miles on it. After driving it and popping the hood I notice that there is smoke coming from both breathers on both valve covers with a little bit of oil getting into the valve covers too.

I didn’t notice any smoke coming from the exhaust. I know on my 73 duster and 74 roadrunner I had a PVC valve that was clogged but I don’t see anything like that on my 67 (did 67’s even have the setup? I realize the 360 engine isn’t original). Can I connect a PVC?

This might come down to engine timing and carb tuning but figured I’d see if I’m missing something obvious.

 

[Longknife]

I don't see a PCV valve set up. If there is none then that is crank case vapors and normal.

 

[Dave6T4]

I would remove oil filler cap from passenger side valve cover and add PCV valve there. Also, the rings may not be fully seated yet. I don't believe those valve covers have oil baffles, either.

 

[1967coronet]

You should swap one of the breathers for a pcv valve.
Get a correct gromet and valve plus a intake fitting and piece of hose.
Oil out of the breathers will or should be gone, smoke/ vapor also.
Plus it will help avoid future oil leaks.

 

[toolmanmike]

Another vote for a PCV valve and for baffles under the cap/pcv valve opening.

 

[RemCharger]

Another vote for rings not seated. Run it hard

 

[Doorkicker]

Just curious. What is the virtue of a PCV valve as opposed to the breather?

 

[dadsbee]

Just curious. What is the virtue of a PCV valve as opposed to the breather?

Breather is to let air in, PCV is to suck **** out and burn it.

 

[Dave6T4]

Actually pulls vapors out of the crankcase using intake vacuum, while pulling fresh air in through filler cap. Instead of waiting for vapor pressure to build up enough in crankcase to push itself out of breather. Before the PVC system, cars had road draft tubes. These were a pipe that plugged into valve cover at one end, while the other end hung down beside engine. The air blowing past the open end of this tube, at road speed, caused a suction that pulled the vapors out. Have you ever seen an old picture of a highway or turnpike, showing a continuous stain on the pavement? This is residue from all those draft tubes.

 

[Doorkicker]

Actually pulls vapors out of the crankcase using intake vacuum, while pulling fresh air in through filler cap. Instead of waiting for vapor pressure to build up enough in crankcase to push itself out of breather. Before the PVC system, cars had road draft tubes. These were a pipe that plugged into valve cover at one end, while the other end hung down beside engine. The air blowing past the open end of this tube, at road speed, caused a suction that pulled the vapors out. Have you ever seen an old picture of a highway or turnpike, showing a continuous stain on the pavement? This is residue from all those draft tubes.

I thought the PVC was activated when the crankcase pressure exceeded a certain level? It actually pulls in fresh air from one side while pulling into the intake on the other?

 

[Doorkicker]

Breather is to let air in, PCV is to suck **** out and burn it.

Welp... that's about a straightforward of an answer you can get
Thanks.

 

[RemCharger]

Welp... that's about a straightforward of an answer you can get
Thanks.

It is. And in the performance world it's worst case scenario. In drag racing you run a crank Evac through the header collectors. Trying to make a vacuum in the crankcase. Next step, a vacuum pump.

 

[Doorkicker]

It is. And in the performance world it's worst case scenario. In drag racing you run a crank Evac through the header collectors. Trying to make a vacuum in the crankcase. Next step, a vacuum pump.

So, you're hitting the nail on the head for me. I've always been under the impression that for a streetcar... use PVC. For a street/strip muscle car use a breather. For a serious engine, use a vac pump. I (assumed?) that the optimal situation is negative crankcase pressure. And I struggle with the idea of just sucking crankcase fumes into the intake...which can vary widely in timing and content, especially when I'm working so hard to hit a given AFR.

 

[toolmanmike]

And I struggle with the idea of just sucking crankcase fumes into the intake...

THat's why the PCV goes to the base of the carburetor. The crankcase fumes are spread out over the ports instead of just one port if it's plumbed into the intake.

 

[tonyp25]

I would remove oil filler cap from passenger side valve cover and add PCV valve there. Also, the rings may not be fully seated yet. I don't believe those valve covers have oil baffles, either.

Appreciate the help! (And all the other answers). If I just timed the engine and tuned the carb would hooking up a PCV valve require me to retune anything?

 

[1967coronet]

Appreciate the help! (And all the other answers). If I just timed the engine and tuned the carb would hooking up a PCV valve require me to retune anything?

No it should not change your timing. Just helps get rid of pressure and oil blow by.