Where does the oil leak come from?

Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's, Olds 98 91-96, Buick Lesabres and Park Avenue 91-96. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
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imidazol97
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Where does the oil leak come from?

Post by imidazol97 »

190,000 mile 1998.

I keep getting oil coming down off the bolts on the oil pan and the starter. It seems to coat the things on the passenger side of the engine.

I can't find liquid oil coming from the valve cover on the front when I go around it with paper towels. I can't get oil by feeling around the valve cover on the rear.

Is it the oil pan gasket? I did run synthetic oil for one oil change about 20K ago. Changing the oil pan seems to be easy with no problems--just drop, replace gasket, and retighten.

Or is there oil coming out somewhere else around a seal around the crankshaft, camshaft?

How do I isolate the source. At this mileage, I hesitate to invest in money and some time to change the oil pan gasket if that's not going to stop the oil drips. I drive 2 miles, park, and I have 6 or 8 drops after an hour on the cardboard protecting the concrete driveway.
Last edited by imidazol97 on Thu Oct 25, 2012 1:17 pm, edited 1 time in total.
nickdalzell1
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Re: Where does the oil leak come from?

Post by nickdalzell1 »

mine is the valve cover gaskets. i really should get on with fixing those...
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01bonneSC
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Re: Where does the oil leak come from?

Post by 01bonneSC »

If your engine is really grimey you can power wash it with some engine degreaser, clean it up, then you can see where seepage is coming from.
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Re: Where does the oil leak come from?

Post by pbrktrt »

The oil pressure sender is a common leak point.
imidazol97
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Re: Where does the oil leak come from?

Post by imidazol97 »

How does the plastic wire holder on the front of the engine below the valve covers come off?

Does it just pull straight up? I tried that but nothing moved.
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Re: Where does the oil leak come from?

Post by 00Beast »

Yeah, it's just slid on there, pull away from the valvecover.
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imidazol97
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Re: Where does the oil leak come from?

Post by imidazol97 »

00Beast wrote:Yeah, it's just slid on there, pull away from the valvecover.
Do you mean pull toward the radiator? Or does it slide up toward the hood?
laimisl
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Re: Where does the oil leak come from?

Post by laimisl »

I have 97, with similar mileage and similar oil leaking location.

What are your findings Imadozol97?

Thanks,

Larry
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Re: Where does the oil leak come from?

Post by RogueSSEi »

I had a common problem, mine was a leaking oil pressure sender, I replaced and problem solved. Best advice, get some good degreaser, brake pats cleaner works excellent too, spray the area around where it is leaking, clean the whole area, take a test spin of 5-10 miles and this should narrow down your search.
imidazol97
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Re: Where does the oil leak come from?

Post by imidazol97 »

laimisl wrote:What are your findings Imadozol97?
I'm still working on it. I've been distracted by the valve cover seep on my 03 in corner above the compressor and a possible failing Timken wheel bearing.

I did find that the sparkplug wire conduit slides straight up along the vertical face of the valve cover. There are T-shapred slides on it that grooves on the conduit fit over. Slide up toward the hood latch on the open hood. Must be glued on at factory or there was a catch on the top of the T slides that broken when pulled against hard.
laimisl
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Re: Where does the oil leak come from?

Post by laimisl »

Thanks RogueSSEi and Imadozol77,

Thing is that it seems like it is leaking more from drivers side, I suspect seal of the crank shaft. As far as I know that would require to pull the engine. Not sure this is something I can afford for now.

Thanks,
Larry
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Re: Where does the oil leak come from?

Post by RogueSSEi »

Mine appeared that way also, after I degreased the bottom end real good, the problem was more apparent and when the oil is hot it will spread and make it look like other parts of the motor are leaking.
laimisl
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Re: Where does the oil leak come from?

Post by laimisl »

Please advise if the below in the picture indicated as Oil Pressure Sender is it:

Image

Thanks,

Larry
laimisl
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Re: Where does the oil leak come from?

Post by laimisl »

My Bonnie has 377k kilometers or 235k miles.

Lots of oil from beneath though.

I know some said to clean it off and see from where it drips.

What are the chances that with 235k miles on it my oil sender is in perfect and non leaking condition?

Thanks,

Larry
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Re: Where does the oil leak come from?

Post by Bob Dillon »

laimisl wrote:Please advise if the below in the picture indicated as Oil Pressure Sender is it:

Thanks,

Larry
That's it. You'll need a 1 and 1/16" deep well socket and a lot of patience to remove it. Use teflon tape on the new one.
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RogueSSEi
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Re: Where does the oil leak come from?

Post by RogueSSEi »

I used either a 3/4" wrench or crescent wrench to remove it. You can lift the right front side, remove the wheel, remove the splash guard, wola. You can get to it better from this angle IMO.
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