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Spark plug change revealed oil in wells

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Spark plug change revealed oil in wells

Post by SCP74 » Sat Feb 08, 2020 2:23 pm

Recently bought 2002 v70xc turbo 2.4. In my efforts to increase gas mileage and doing maintenance the seller said we're done up to date has revealed that oil is pushed up into spark plug wells in 2 of the middle cylinders. Basically, 3 and 4 moving from left to right revealed that the oil had risen up through well and soaked the spark plug head up through the most part of the threads.

Of course after telling this to the Volvo mechanic who was said to have worked on the car, (don't ask), said that it would be a job for him. Where can I start to determine what the issue is PART OF?? I know that the vehicle is sick, and needs much done to get things back to stage 0. Right now, need to move gas mileage beyond 11 mpg!!

First thing said on Google was the answer to my problem was NEW valve cover gasket.
How can I determine what to do FIRST, in solving the greater problem here? I'm changing oil today, and will see how my gas mileage improves. One thing I noticed after changing plugs from volvo OEM plugs, that could have been original (?), Was that the color, and quantity, shown by dipstick was much lower and also cleared up from black to clear bronze.
Thanks for the help in advance, in bringing light to the issue.

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Re: Spark plug change revealed oil in wells

Post by quietlymknnoise67 » Sat Feb 08, 2020 2:55 pm

Check Oil Filler Cap Gasket

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Re: Spark plug change revealed oil in wells

Post by crlande » Sat Feb 08, 2020 3:15 pm

Likely dripped down from the top which most likely came from, as already stated, the oil filler cap gasket. It gets brittle and should get replaced regularly.

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Re: Spark plug change revealed oil in wells

Post by erikv11 » Sat Feb 08, 2020 3:28 pm

Root problem: very likely the PCV is clogged and needs servicing. Remove the oil cap and do a "glove test" with the engine running. You can find videos explaining this very simple test.

Contributing problem: almost certainly the rubber gasket on the oil cap is old and brittle, as pointed to by other posters.

0.000000001% chance: oil is leaking into the spark plug recess from the seam on the cam cover.

There is no valve cover on these engines, but there is a cam cover.
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Re: Spark plug change revealed oil in wells

Post by abscate » Sat Feb 08, 2020 4:00 pm

Yeah, Google will you get your into trouble fast in mechanics.

Replace plugs and drive for a week. See if oil returns
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Re: Spark plug change revealed oil in wells

Post by misha » Sun Feb 09, 2020 9:53 am

Yep....replace oil cap seal.
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Re: Spark plug change revealed oil in wells

Post by amblerman » Mon Feb 10, 2020 12:53 pm

In case it's not obvious.

Take your oil cap off.. flip it over.. there should be a large rubber washer there. That's the oil seal people are talking about.

Follow link in this post to see picture:

But please verify that is the correct one for your vehicle before buying.


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