| Oil breather [message #222591] |
Sun, 15 September 2013 20:15  |
skip2
Messages: 544
Registered: September 2011
Location: Winter Haven,FL (center o...
Karma: 3
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My po rebuilt the 455 and turned it into a hot rod motor for real with all the eldelbrock goodies he could. He has a PVC valve on the right rocker cover and on the left is the old fashion oil breather cap with the heavy baffle screen in it just like an old street rod. When you get out after a trip you can smell oil. But no leaks to be found, I'm believing I smell the crankcase venting through the old style breather . Anyone out there with experience have any ideals if they think it would be ok to cap this breather and let the single pcv do it's job or try and put a second pcv in its place?
74 Canyon Lands, FiTech,
3.7 FD LSD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
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| Re: Oil breather [message #222597 is a reply to message #222591] |
Sun, 15 September 2013 20:56  |
LarryInSanDiego
Messages: 336
Registered: September 2006
Karma: 0
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That's why crankcase breathers are routed from the air cleaner, even the open element types. Required since crankcase emissions got more tightly regulated (remember road draft tubes?). Think of a PCV as a one way check valve (for backfire crankcase fire protection) with a calibrated internal vacuum leak. Installing an incorrect or additional PCV will create multiple idling and low speed issues that may be difficult to compensate for, especially in a carbed application. I imagine that EFI would be far easier to deal with.
I suggest performing a thorough leakdown test. Hopefully the rings are broken in and cylinder walls honed properly.
Larry Engelbrecht
San Diego, CA
'73 26' ex-Glacier
TZE063V100319 03/07/73
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| Re: Oil breather [message #222599 is a reply to message #222591] |
Sun, 15 September 2013 21:08 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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GM used that same breather on many Olds applications and into the 80s on Turbo Buicks and the 89 Turbo Trans Am. In ALL cases they were piped back into the induction side to reburn the vapors.
John Lebetski
Woodstock, IL
77 Eleganza II
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| Re: Oil breather [message #222600 is a reply to message #222591] |
Sun, 15 September 2013 21:13 |
Dennis S
Messages: 3046
Registered: November 2005
Karma: 2
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| skip2 wrote on Sun, 15 September 2013 20:15 |
My po rebuilt the 455 and turned it into a hot rod motor for real with all the eldelbrock goodies he could. He has a PVC valve on the right rocker cover and on the left is the old fashion oil breather cap with the heavy baffle screen in it just like an old street rod. When you get out after a trip you can smell oil. But no leaks to be found, I'm believing I smell the crankcase venting through the old style breather . Anyone out there with experience have any ideals if they think it would be ok to cap this breather and let the single pcv do it's job or try and put a second pcv in its place?
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The breather (originally in the left valve cover) serves as the inlet for clean air to allow the flow through the crankcase and out the PCV valve.
Can you replace the "old fashioned oil breather" with the standard and attach with a breather hose to the air filter? This would return the flow to original.
Dennis
Dennis S
73 Painted Desert 230
Memphis TN Metro
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| Re: Oil breather [message #222605 is a reply to message #222600] |
Sun, 15 September 2013 21:42 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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You can get that adapter that plugs into the valve cover at AutoZone. Then a simple hose (I used a heater hose) will fit between it and the air cleaner.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: Oil breather [message #222624 is a reply to message #222605] |
Mon, 16 September 2013 01:40 |
jim kanomata
Messages: 257
Registered: March 2007
Location: fremont,ca
Karma: 12
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I was contacted by the warehouse sales rep that showed me a unit that will eliminate the mist from the valve cover.
Around $200.
I think your engine was not rebuilt carefully, too much blow by the piston.
Possible broken rings.
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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| Re: Oil breather [message #222628 is a reply to message #222624] |
Mon, 16 September 2013 06:17 |
skip2
Messages: 544
Registered: September 2011
Location: Winter Haven,FL (center o...
Karma: 3
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Senior Member |
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Jim was it an edelbrock rep? When do you sleep?
Skip Hartline
74 Canyon Lands, FiTech,
3.7 FD LSD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd
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