Valve Cover Leaks
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
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From: San Diego California
Valve Cover Leaks
This seems at first to be a simple problem: oil leaks from valve cover breathers.
At first, it was a Moroso breather that leaked, and now it's a new replacement breather that weeps oil, as the pictures above show.
Also leaking on that left valve cover is the filler cap.
Yesterday it was the Right Valve Cover Breather that was leaking, but now it appears it has stopped and moved over to the left cover. It is dry on the underlip of this breather right now.
I'm thinking there is high pressure oil present for some reason in this area and causing these leaks. There was a new high pressure/volume oil pump installed during this 383 build. Would that cause this problem? And if so, how can this problem of leaks be fixed?
Thanks in advance.
Steve
At first, it was a Moroso breather that leaked, and now it's a new replacement breather that weeps oil, as the pictures above show.
Also leaking on that left valve cover is the filler cap.
Yesterday it was the Right Valve Cover Breather that was leaking, but now it appears it has stopped and moved over to the left cover. It is dry on the underlip of this breather right now.
I'm thinking there is high pressure oil present for some reason in this area and causing these leaks. There was a new high pressure/volume oil pump installed during this 383 build. Would that cause this problem? And if so, how can this problem of leaks be fixed?
Thanks in advance.
Steve
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
Thanks Jim.
Any photos, product info?
I have a feeling the higher oil pressure is shooting oil up the cam follower tubes to the rockers at a rate higher than the breathers can handle.
Steve
Le Mans Master
Joined: Apr 2011
Posts: 6,284
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From: Hermosa
Without the PVC pulling a vacuum and a valve cover with a vent then the blowby pressure will have to be relieved somehow.
So it is probably being forced out your vents and oil cap around the rivit.
Like Jimt I used a breather cap with vent like this one;
http://www.ebay.com/itm/Spectre-1-Push-In-Style-Valve-Cover-Breather-with-5-8-PVC-Vent-Tube-Chrome-/381063152175?pt=Motors_Car_Truck_Parts_Accessories&hash=item58b922422f&vxp=mtrThe vent connects to the air cleaner so it sucks in filtered air.
Then on the other valve cover has a PVC valve and a connection to the intake manifold vacuum at the base plate of the carb.
So it is probably being forced out your vents and oil cap around the rivit.
Like Jimt I used a breather cap with vent like this one;
http://www.ebay.com/itm/Spectre-1-Push-In-Style-Valve-Cover-Breather-with-5-8-PVC-Vent-Tube-Chrome-/381063152175?pt=Motors_Car_Truck_Parts_Accessories&hash=item58b922422f&vxp=mtrThe vent connects to the air cleaner so it sucks in filtered air.
Then on the other valve cover has a PVC valve and a connection to the intake manifold vacuum at the base plate of the carb.
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
I just got done talking to my A&P mech at the airport. I told him of the problem and he came up with the same idea:
The engine is really missing that suction it gets with the PVC plumbing to the air cleaner/intake system.
So, I did this:
And now for a drive to the beach. Will report back on the findings.
Steve
The engine is really missing that suction it gets with the PVC plumbing to the air cleaner/intake system.
So, I did this:
And now for a drive to the beach. Will report back on the findings.
Steve
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,487
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From: New Or-leens Loo-z-anna
Rookie suggestion, but I have aftermarket valve covers:
The previous owner installed a high-volume oilpump.....when I adjust the hydraulic valves----oil is squirting out of the engine bay at my wife's car
I installed PVC valves rated for a 3.0Liter engine/I put a PVC valve on EACH valve cover connected together with a T-fitting....I installed one breather cap at the other end of one valve cover....
now there is no more oil leaking/blowing out of the breather and the engine idles well because the two PVCs act independently (rather than 1 oversize PVC valve gulping lots of pressure instantly)
It definitely keeps gunk/sludge/moisture from building up in the valve covers/rocker arms/oil galley!
like I said......rookie sugg.
The previous owner installed a high-volume oilpump.....when I adjust the hydraulic valves----oil is squirting out of the engine bay at my wife's car
I installed PVC valves rated for a 3.0Liter engine/I put a PVC valve on EACH valve cover connected together with a T-fitting....I installed one breather cap at the other end of one valve cover....
now there is no more oil leaking/blowing out of the breather and the engine idles well because the two PVCs act independently (rather than 1 oversize PVC valve gulping lots of pressure instantly)
It definitely keeps gunk/sludge/moisture from building up in the valve covers/rocker arms/oil galley!
like I said......rookie sugg.
Last edited by doorgunner; Dec 8, 2014 at 11:43 AM.
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
I installed PVC valves rated for a 3.0Liter engine/I put a PVC valve on EACH valve cover connected together with a T-fitting....I installed one breather cap at the other end of one valve cover....
now there is no more oil leaking/blowing out of the breather and the engine idles well because the two PVCs act independently (rather than 1 oversize PVC valve gulping lots of pressure instantly)
now there is no more oil leaking/blowing out of the breather and the engine idles well because the two PVCs act independently (rather than 1 oversize PVC valve gulping lots of pressure instantly)
I just got back from a half hour drive;
Even the left side was dry also.
This may be enough. Time will tell.
Steve
Le Mans Master
Joined: Apr 2011
Posts: 6,284
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From: Hermosa
one should be suffecient. Does that valve cover have a baffle in it under that PCV hole? If not you will be sucking some excessive oil mist into your intake. Not a big deal just be aware of it.
Also that valve cover breather is drawing in unfiltered air into your crank case unless some kind of filter is used.
doorgunner you got a point, and I could see it if the engine has more than average blowby or pretty low vacuum that two may be better. But if one works....
Also that valve cover breather is drawing in unfiltered air into your crank case unless some kind of filter is used.
doorgunner you got a point, and I could see it if the engine has more than average blowby or pretty low vacuum that two may be better. But if one works....
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Le Mans Master
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From: El Cajon California
Thread Starter
Melting Slicks
Joined: Oct 2013
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From: San Diego California
Steve
Drifting
Joined: Apr 2002
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From: Manhattan Beach Ca
Breathers just leak when they get saturated without pcv suction, its just the way it is. I put little circular thick cloth material under the breathers to soak any drips so they don't end up on the headers. Have to replace about every two months of everyday driving. 0.02
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
Breathers just leak when they get saturated without pcv suction, its just the way it is. I put little circular thick cloth material under the breathers to soak any drips so they don't end up on the headers. Have to replace about every two months of everyday driving. 0.02
Steve
Le Mans Master
Joined: Oct 2010
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From: melbourne florida
2023 C3 of the Year Finalist - Modified
use the check valve for a power brake booster , way more flow than any P.C.V valve. cheap and effective. us Virginia guys called it a West Virginia Vacu Pan.
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
Le Mans Master
Joined: Oct 2010
Posts: 6,900
Likes: 833
From: melbourne florida
2023 C3 of the Year Finalist - Modified
the little plastic check valve on the brake booster pulls way more volume than any p.c.v valve. get a spare one of those and stick it in place of the p.c.v . is that what you were confused about?
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
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From: San Diego California