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| | | | Joined: Apr 2005 Posts: 67 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2005 Posts: 67 | I saw a pic of where a man took a freeze plug with a hole and grommet and a PCV vale , removed the downdraft tube and replaced it with this Pcv vale with a vacuum line running from a port on the carb. Is this a good idea to remove the downdraft tube ????
Is this enough crankcase ventilate???? (235)
SlickT
Last edited by Slickt; 01/27/2009 2:05 PM.
| | | | | | ZooKeeper Unregistered | | ZooKeeper Unregistered | It's "PCV" valve(not PVC) & yes it's been done many times, BUT don't forget you have to have a breather cap on the valve cover to make the system breath correctly...Joe | | | | | Joined: Nov 2005 Posts: 266 Shop Shark | | Shop Shark Joined: Nov 2005 Posts: 266 | I would keep the road draft tube. Isn't there a way you can shorten it and have it drain into a jar of some sort?
My 250 has the PCV and breather cap setup, and even with a new valve and hose, crud still gets blown out of my breather cap and down the valve cover making a greasy mess. | | | | | Joined: Apr 2005 Posts: 67 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2005 Posts: 67 | Thanks , I was just wondering if that would work.
SlickT | | | | | Joined: Feb 2000 Posts: 769 Shop Shark | | Shop Shark Joined: Feb 2000 Posts: 769 | If you were to shorten your road draft tube and put a jar on the end to catch the driping, it would no longer work. The road draft tube works by vacuum. As the vehicle travels down the road, the air passing over the end of the road draft tube creates a vacuum in the tube, which in turn draws crank case fumes out. | | | | | Joined: Oct 2001 Posts: 3,458 Extreme Gabster | | Extreme Gabster Joined: Oct 2001 Posts: 3,458 | If you can find one, you could snag the oil filler/breather off a GMC 270 or 302 with factory PCV. The road draft tube is replaced with a tube that has a small paper air filter element for the breather and an oil filler cap. The valve cover doesn't have an oil fill hole. Any oil would have to travel up the long tube and through a couple of baffles to puke out the breather.
Paint & Body Shop moderator
A lone amateur built the Ark. A large group of professionals built the Titanic. | | | | | Joined: Apr 2005 Posts: 1,107 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,107 | my 51 350 has the pcv set up and with a little mod i did away with the oil bath and inserted a dry element filter. i have nothing blowing back out of it. i just got done adding the same set up to my 40 AC252. not because of the draft tube but i dont like the vented valve cover. it's too easy for foriegn material doesnt belong in the engine finding its way in at that area. | | |
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