PCV Question

[Hijinx]

One other thing that I have noticed since putting the Demon on. I had to remove the PCV because it has only one large manifold vacuum fitting. After she's warm, I have what looks like light smoke or steam coming from the opposite valve cover breather. Could that be from not having a positive crank case vent in place providing vacuum through the system? Why would I see smoke?

 

[Hijinx]

OK, I have pretty much figured out the smoke is due to no positive crank case vent. However, the only line I have to T off of is the brake booster line and somehow I dont think that's a good idea. Any suggestions?

 

[JohnZ]

Which Demon do you have? Every one I've seen (other than the all-out chokeless race versions) has three vacuum ports - one large (for PCV) and two small ones for the distributor vacuum advance line - one for manifold vacuum, and one for "ported" vacuum. You definitely need the hose from your rocker cover PCV valve to the carb base, or you're going to have oil mist everywhere due to lack of positive ventilation.

 

[Hijinx]

Yea, I do have 3, but I need 4. I have the brake booster hooked to the rear large manifold vacuum port. This is the one I was thinking about T'ing off for the PCV. However, I'm not sure if that will cause a decrease in vacuum pressure to the brake booster that could cause braking problems.

I have the front small vacuum port (ported or timed vacuum) hooked to the EGR.
I have the second front vacuum port (direct manifold vacuum) hooked to my distributer vacuum advance.

What are you thoughts on this John. I'm not much on vacuum.

 

[Hijinx]

Well, reinstalling the PCV did the trick, no more smoke. Have it T'd off of the brake booster line. Hopefully, that will not cause me any trouble.

 

[Hijinx]

Interesting sidebar to this issue. I have had a small rear main seal leak for some time now. I noticed the other day that it had gone from a small leak, to something pretty substantial. After replacing the breather I had put in place after my carb swap with a new PCV and tieing it to the Brake booster vacuum, my leak is back to a small drip. Interesting how important crank case venting is!