Crankcase Vent Tube

[LaGrasta]

What is this for?

 

[Asa]

if i'm thinking correctly, the vent tube lets built up pressure from gases, and everything heating up escape, i also think that a vacuum introduced into the crankcase will increase HP, can't for the life of me remember why... helps the rings seal better maybe?

 

[Falcon62]

They were used pre-PCV to ventilate crankcase vapors. IMO, Not worth having, or using, unless you have a bone stock collector car where originality is important.

 

[LaGrasta]

In ordering a new chrome valve cover, I could order one with the oil fill and pcv holes and block this tube off altogether? I'm on board with that. To be sure we're all talking about the same tube, anyone that can post a pic, please do so. Thanks.

 

[BIGREDRASA]

You are absolutely right, order the later style valve cover. You may have to fabricate the block-off plate for the road draft tube. The tube looks like a can bolted to the side of the block, with a pipe sticking out of it. The Positive Crankaces Ventilation (PCV) Valve is one emission control device that actuallly improves engine life as well as the environment.

 

[Falcon62]

No block off plate necessary, it takes a standard core plug (don't know the size off the top of my head 'tho). I think I have a photo somewhere....

I knew it was out there someplace 8) Check out the brass freeze plug just forward of the distributor. I can get a more detailed photo tomorrow if needed.

 

[LaGrasta]

I got it. That's what I thought we were all talking about. Any reason I couldn't just use a vented oil fill cap with a pcv installed in the line?

 

[BIGREDRASA]

The only thing is where you'll connect the PCV line. If you don't access to a later model, PM me with your e-mail and I'll send pics of vacuum line routing.

 

[Falcon62]

Ford used a hard line PCV setup that connected where the down draft tube bolted up on the early Falcons, but I don't know what years had them. The 170 in my son's Falcon has one. However, I'd just plug it, and run a later valve cover and PCV like on my engine.