Where is the oil going??
Thread Starter
Instructor
Joined: Sep 2003
Posts: 140
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From: charleston sc
Where is the oil going??
I have a friend who has a 1973 and is having a mysterious oil loss... no leaks (on garage floor) no obvious smoke clouds yet he is losing 1 quart of oil per 150 - 175 miles. When I say no obvious smoke cloud of course I mean anything that would certainly be evident by that amount of oil loss... any clues, suggestions?
Race Director
Joined: May 2002
Posts: 14,376
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From: Check this riff........
Re: Where is the oil going?? (Voodoo93)
thats a huge amount, if no leaks, I cant believe there isn't smoke clouds. Perhaps the intake valve seals are bad. There would only be smoke on deceleration and maybe thats why he does not see smoke.
Drifting
Joined: Jun 2000
Posts: 1,955
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Re: Where is the oil going?? (BigBadOrange)
The 454 in my Suburban loses a quart every 1000 miles or so, but also shows no signs of leakage or smoking. Heads were freshened 30K miles ago, shortblock has 122K miles on it and makes plenty of power.
Looking forward to ideas on this one...
Jeff
Looking forward to ideas on this one...
Jeff
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Re: Where is the oil going?? (Voodoo93)
I may have similar problem. I suspect caused by a leaking intake gasket since I did not put gasket sealant on the intake gaskets when I installed them with the new heads (that's why I don't suspect valve seals, new heads). I see blue smoke ONLY on decelleration and even worse, only when I have it on the dyno and can see the smoke puff out. I add about .5 quart every 2-3 weeks of cruising and no puddles on the garage floor.
Thread Starter
Instructor
Joined: Sep 2003
Posts: 140
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From: charleston sc
Re: Where is the oil going?? (TedH)
Thanks for the inputs... the local Corvette shop here stated he may be losing it through his PVC since he has aftermarket (Mickey Thompson) valve covers on which have no baffle below the PVC filter. But wouldn't that still cause a great amount of smoke if he was pumping that much oil through the intake?
Race Director
Joined: Mar 2001
Posts: 11,322
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From: Living in the Hartland
Re: Where is the oil going?? (Voodoo93)
My vote is valve stem leaks, just stripped my eng down and had a thick sludge on the top of the intake valves and a lot of deposit on the pistons. Not much smoke, only on warm start up but it was drinking oil.
Melting Slicks
Joined: Jul 2002
Posts: 3,000
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From: Boulder Creek California
Re: Where is the oil going?? (Fevre)
I was loosing just a little less than this, after I changed out my intake I only lose a little. After my recent cam install, including new valve seals, I loose zero. I too had no noticeable smoke.
-Chris
-Chris
Instructor
Joined: Nov 2002
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Re: Where is the oil going?? (RUXperienced)
Valve stem seals on the intake valves, they will suck oil but not enough to cause smoke. I learned this the hard and costly way rebult engine twice first time I thought rings did not set . Second was to replace rings then found that wrong seals were put on by machine shop.
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Le Mans Master
Joined: Jan 2003
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From: Tuttle OK
Cruise-In VIII Veteran
Re: Where is the oil going?? (Voodoo93)
This may not help, but I had a similar (not quite as bad) problem. Baffled me for a while, but the fix was simple. Valve covers. I could never spot a bad leak, no smoke, but could occasionally smell oil burning. Noticed some small leaking at the rear of the valve covers (Moroso) so I changed gaskets, didn't work. Finally bought some bow tie covers and the problem was solved.
In hind sight, the oil was being mostly burned by the exhaust manifolds so other than smell (when conditions were right), I just didn' see it.
In hind sight, the oil was being mostly burned by the exhaust manifolds so other than smell (when conditions were right), I just didn' see it.
Safety Car
Joined: Jan 2001
Posts: 4,660
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From: South Central Louisiana
St. Jude Contributor
Re: Where is the oil going?? (Avette4me)
I loose about the same amount of oil in my 71 through the crankcase breathers.
Also, I hope that the oil is not going into the interior via the oil gauge line. :confused:
Also, I hope that the oil is not going into the interior via the oil gauge line. :confused:
Melting Slicks
Joined: Jul 2001
Posts: 2,609
Likes: 12
From: Massapequa Park NY
Re: Where is the oil going?? (Voodoo93)
Had a similar problem in my Mustang that I thought was the intake gasket - notorious on the FE motors. Anyway that is a lot of oil to burn, I was going through a qt every 100 - 150 miles. Could smell it on clothes & see it on the car. IIRC - puff of smoke of deceleration is an indication of bad intake valves or seals, on acceleration bad exhaust valves or seals, constant oil is bad PVC or rings. Excessive oil in the air cleaner can be an indication of bad rings or PCV problems also. The PVC system is an open system - oil fumes are drawn into the engine to burn at a controlled amount. The make up air is drawn into valve cover through the breather on the opposite cover. Should be 4-5" of vaccum at the breather.
In my case it was valve guides that got wiped out by tapered valve stems. Poor valve job by the first machine shop.
By the way - take a white rag & wipe off the back of the car after burning up a qt. You might be surprised what you find.
[Modified by 70BBvert, 6:06 PM 9/23/2003]
In my case it was valve guides that got wiped out by tapered valve stems. Poor valve job by the first machine shop.
By the way - take a white rag & wipe off the back of the car after burning up a qt. You might be surprised what you find.
[Modified by 70BBvert, 6:06 PM 9/23/2003]
Burning Brakes
Joined: Mar 2001
Posts: 1,211
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From: Nashville TN
Re: Where is the oil going?? (70BBvert)
This small breach caused my car to consume 1 quart overy 85 miles on the freeway.
I have also found that with my Weiand intake I need to rtv the intake gaskets down otherwise it drinks oil.
I have also found that with my Weiand intake I need to rtv the intake gaskets down otherwise it drinks oil.