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Oil Leak Only In High Speed/High RPM (SC400)

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Old 06-27-12, 11:14 PM
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OG Dada
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Default Oil Leak Only In High Speed/High RPM (SC400)

I'm about to do an oil change like right now, right now. And I wanna find out if anybody can figure where the leak is coming from, so if I need to drain my oil to fix it, I wouldn't do the oil change right now. Here's the scenario, I know for a fact that my SC is leaking oil, but not too much (at first) to concern me. The last 7500 miles, I've never driven much freeway, and since I know that it is leaking oil I check it on the daily, and not once did the oil level drop for the entire 7500 miles. About a week ago, I drove my SC from San Diego to Rancho Cucamonga which is roughly 360+ miles back and forth, and roughly 70-80mph speeds. Then my oil level dropped rapidly, I lost about half according to the dipstick. It has never leaked this much before, so I'm guessing it leaked a lot due to me driving in high speed conditions or high RPM. Here are some pics for better understanding of how it looks like under my engine.

From under the car;






A bolt of the engine oil pan.





This is where it seem to be concentrated.



From the engine bay;



Power steering pump location.



Between the valve cover, power steering pump and headers.


Under the drive belt tensioner, atop of the alternator.


Driverside cam plastic cover.







The oil reached the 3rd catalytic converter, which is also the reason it got me thinking its because of high speed conditions. I only usually drive below 55mph on a regular basis and the oil have never reached this part before. As you can see the oil is fresh and wet.


I know, it is highly filthy down there right now. Like I said, there's an oil leak. I haven't cleaned anything under there ever since I got my SC, but it have never been this filthy trust me.

Okay, some parts I was thinking of where leak may come from;

Valve Cover Gaskets - I've already fixed the leak coming from here when I first got my SC. I'm not crossing it out though since its not impossible to start leaking again, although the oil isn't too much based on the pics.

Front Main Seal? - Not sure at all how to detect this without removing the plastic covers.

Engine Oil Pan Gaskets - I jacked up the engine at the oil pan with a couple of 2x2 wood when I did the engine mounts, not sure if it may have developed a leak from that, but based again on the pics, it seems to come from a higher location, so not sure.

Distributor Seals? - I've never come across a thread with a leak coming from this location for SC400's. So I'm not sure at all if it may cause this much of oil leak?

Oil Filter? - Can it develop a leak when it's getting close to its due oil change? But then again, it seems that the leak is coming from a higher location unless the it is getting blown by the wind upward?

What is this cylinder part called? This have bothered me a lot ever since I got my SC, because its always been wet of oil.


That's all I can think of right now... I know a lot of people will say check this and check that, if I know how to properly check those parts I would've done it already, so PLEASE to anybody who's gonna suggest what to check PLEASE tell me how as I have no idea. A basic instructions will do for me as I'm a hands on guy. Thank you so much CL for everything. This forums have literally done all my fixings for me.

Last edited by OG Dada; 06-27-12 at 11:25 PM.
Old 06-28-12, 05:11 AM
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blk&blu*j
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I'm not a V8 guy but that part appears to be a timing belt tensioner.

GL.
Old 06-28-12, 08:02 AM
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Get some degreaser or brake clean and spray off all the dirt and oil from there, take her for a good drive, then come back and crawl under there and see if you see any new signs of leaking. With everything clean, you'll be able to pin point where it's coming from a little easier.
Old 06-28-12, 01:49 PM
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OG Dada
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Originally Posted by blk&blu*j
I'm not a V8 guy but that part appears to be a timing belt tensioner.

GL.
Thanks for the info. Can anybody tell me where can oil leak somewhere there?

Originally Posted by TweakTech
Get some degreaser or brake clean and spray off all the dirt and oil from there, take her for a good drive, then come back and crawl under there and see if you see any new signs of leaking. With everything clean, you'll be able to pin point where it's coming from a little easier.
That's the plan right now. Only problem is I live in a condo and don't have a garage, so I'm at the mercy of a friend to make mess in his driveway... Thanks though, I appreciate the info.
Old 06-28-12, 11:13 PM
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chargerfan
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come over tommorrow or sat morn bro, my driveway is ready to get dirty for you
Old 07-05-12, 07:48 AM
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I've finally located where the leak is coming from. Looks to be like camseals are leaking and wasn't done together with the timing belt by whoever did it. And a possible front main seal, haven't gone that deep yet, but unlikely. Anyways, can anybody please link me a DIY for the camshaft seals? I've been searching for hours and couldn't find any. Thanks in advance CL!
Old 08-30-12, 12:15 PM
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Never mind.

Last edited by OG Dada; 08-30-12 at 07:18 PM.
Old 12-18-12, 05:51 PM
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Originally Posted by KingPhilip
I've finally located where the leak is coming from. Looks to be like camseals are leaking and wasn't done together with the timing belt by whoever did it. And a possible front main seal, haven't gone that deep yet, but unlikely. Anyways, can anybody please link me a DIY for the camshaft seals? I've been searching for hours and couldn't find any. Thanks in advance CL!
Did you find a DIY, I'm having exactly the same leak.
Old 12-21-12, 07:07 PM
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I am also i just looked under and I can see it drip its driving me crazy !
Old 02-28-13, 12:58 PM
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Originally Posted by KingPhilip
Never mind.
So what happened?
Old 02-28-13, 01:32 PM
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I was about to suggest it was a cam seal but you sort it out. I had a similar leak because of the turbo building extra pressure on the valve cover.
Check before if they are only the rear cam seals, as they can be removed without taking the cams out.
Old 07-22-14, 09:14 AM
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I removed both timing covers near the distributors and it looks dry up there, I turned the car on and crawled under and could see oil building up where the oil filter attaches to but higher, the ac compressor is also wet under. Looked up top again behind timing belt and it's dry. Any ideas?
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