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Old 05-12-2023, 07:28 AM   #1
chrismoore701
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Insane oil leak

Asking for a friend who just got his engine fired up after being built 3 years ago. Older motor Fired up with synthetic oil. Did a break in. lost over 2 courts of oil in just a couple hundred miles.

He has compression

sees oil on the threads of the plugs. I am thinking valve seals, how do you check this
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Old 05-12-2023, 08:17 AM   #2
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Re: Insane oil leak

What kind of engine?
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Old 05-12-2023, 09:13 AM   #3
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Re: Insane oil leak

.
Quote:
Originally Posted by chrismoore701 View Post
Asking for a friend who just got his engine fired up after being built 3 years ago. Older motor Fired up with synthetic oil. Did a break in. lost over 2 courts of oil in just a couple hundred miles.

He has compression

sees oil on the threads of the plugs. I am thinking valve seals, how do you check this
Pull one or both exhaust manifolds off and if it’s seals you’ll see oil crud on the valve stems right down on to the backside of the valves.
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Old 05-12-2023, 09:28 AM   #4
72c20customcamper
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Re: Insane oil leak

2 quarts in a couple hundred miles . I would think it would be smoking pretty bad . Can’t see seals doing that much , my 68 327 uses oil and fouls the #1 plug regularly so I know the seals are bad but it doesn’t use that much and it hardly smokes at startup . Any plugs fouled?
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Old 05-12-2023, 09:31 AM   #5
72c20customcamper
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Re: Insane oil leak

Did he break it in with synthetic oil? If so nothing broke in I would drain it put break in oil in it and redo the procedure.
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Old 05-12-2023, 12:40 PM   #6
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Re: Insane oil leak

Pull a couple of the oily plugs. If the tips are also oil coated, could be the valve seals. But as mentioned, a normal sign of burning oil is blue exhaust smoke.

Another reason the outside of the spark plugs could be oily is leaking valve cover gaskets. But that much leakage should show up on the floor.

OEM valve covers or aftermarket? Some aftermarket skip the baffles for the PCV connections. No baffles could cause excessive oil consumption.
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Old 05-12-2023, 01:58 PM   #7
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Re: Insane oil leak

on tv years ago guy had similar issue with a fresh rebuild on a corvette.. turns out the intake manifold was bad and it was sucking oil down the ports it was an episode of fantomworks
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Old 05-12-2023, 02:40 PM   #8
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Re: Insane oil leak

thanks guys, going to try to do the break in again
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Old 05-12-2023, 09:24 PM   #9
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Re: Insane oil leak

Quote:
Originally Posted by 72c20customcamper View Post
did he break it in with synthetic oil? If so nothing broke in i would drain it put break in oil in it and redo the procedure.
x2
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