Working on my 41 with a 350, but it has an older intake with the oil filler tube in it, and a "breather tube" (not sure that's what it's called). I want to use the closed valve covers you see on it. Based on my research on this site, I'm thinking I can run a PCV line from that "breather tube" in the oil filler tube to either a port on the base below the carb or into the base of the air cleaner (yet to be determined). Is that correct? Will the engine breathe properly with it set up that way? Thanks.
~ Victor 1941 3/4-Ton Pickup (in process). Read about it in the DITY Gallery 1955 Grumman Kurbside "Doughboy" 235/3 on tree w/ OD 1957 3100 - moved on 1959 C4500 Short Bus "Magic Bus" - moved on 1959 G3800 1 Ton Dually "Chief" - moved on 1958 C4400 Viking "Thor" ~ moved on to fellow Bolter
Will the engine breathe properly with it set up that way?
The short answer is "no". A PCV system needs two holes, one to let air into the engine, and another for the PCV valve to draw air back out. The original engines that used that manifold had a hole in the block back beside the distributor and a baffled canister under the intake that allowed air to be vented through a breather tube beside the bellhousing. That system stopped being used with the 2nd-generation 327's in about 1965 or so, I believe. Those engines could be converted to PCV by installing an adapter in the block to eliminate the road draft tube and attaching a PCV valve to that port. The small tube in your photo was used with a sealed oil fill cap to draw air from the underside of the air cleaner.
If you use that fill tube nipple to connect to a PCV, you're going to need to vent the passenger's side valve cover to let some air into the engine. Just drill and tap the top of the cover for a pipe thread to hose nipple fitting and run at least a 3/8" hose to the "clean" side of the air cleaner. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Thanks Jerry. That's what I was hoping to avoid...drilling into those finned valves covers. Don't know why...guess they are of no use without holes in them. I pulled them off and put some covers on that have breathers on both sides. I'll get a valve in it and be good to go.
~ Victor 1941 3/4-Ton Pickup (in process). Read about it in the DITY Gallery 1955 Grumman Kurbside "Doughboy" 235/3 on tree w/ OD 1957 3100 - moved on 1959 C4500 Short Bus "Magic Bus" - moved on 1959 G3800 1 Ton Dually "Chief" - moved on 1958 C4400 Viking "Thor" ~ moved on to fellow Bolter
If there's room between the valve cover and the firewall, a 90 degree fitting tapped into the very back of the passenger's side cover would be virtually invisible. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Thanks Jerry and Dave. Guess I need to search the Tech Tips next time--duh! That's a great write up by Mark and just what I need. I'm a little anxious the get the truck on the road this season, so will work on those aluminum covers after the truck is road worthy. Thanks again.
~ Victor 1941 3/4-Ton Pickup (in process). Read about it in the DITY Gallery 1955 Grumman Kurbside "Doughboy" 235/3 on tree w/ OD 1957 3100 - moved on 1959 C4500 Short Bus "Magic Bus" - moved on 1959 G3800 1 Ton Dually "Chief" - moved on 1958 C4400 Viking "Thor" ~ moved on to fellow Bolter
