Oil on the spark plug
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Having oil consumption issues?
oil on top of the plug or on the engine side? oil on the top is a valve cover leak. dry black residue inside could be carbon from a bad fuel misture. wet & black is likely oil. how many miles?
Could be many things including worn Valve seals. What vehicle are we talking about? Have you tested the compression in that cylinder?
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The smoke is oil. Its probably the valve seals if its otherwise running fine. You could check compression if you have a tester though.
+1 tomcat27. Is the oil on the outside and if so, some engines have o-ring seals that would need to be replaced.
Have you pulled all the plugs and are they all wet with oil?
It could be a combination of worn valve guides and their seals.
It's a labor intensive job and they would likely simply repace the heads with some re-manufactured ones. I'm guessing at 1,000 to 1,500 bucks.
What's the market value of your 13 year old Chrysler?
You could simply try using a heavier grade of oil like 5W-40 or 5W-50 and see if that at least stops the noticeable oil burning.
It could be a combination of worn valve guides and their seals.
It's a labor intensive job and they would likely simply repace the heads with some re-manufactured ones. I'm guessing at 1,000 to 1,500 bucks.
What's the market value of your 13 year old Chrysler?
You could simply try using a heavier grade of oil like 5W-40 or 5W-50 and see if that at least stops the noticeable oil burning.
Originally Posted By: redd
how much are we talking here for valve seals at a repair shop?
It's not that big a job; the head can stay on. A couple hours maybe
how much are we talking here for valve seals at a repair shop?
It's not that big a job; the head can stay on. A couple hours maybe
Is it just one plug or all of them?
I had one on the Taurus, turns out after cleaning the plugs and run it again for a few hundred miles just to check, one of the plug has a hairline carbon track on the ceramic insulator.
I had one on the Taurus, turns out after cleaning the plugs and run it again for a few hundred miles just to check, one of the plug has a hairline carbon track on the ceramic insulator.
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What engine? If its one of the ones like the 2.4 that has spark plugs through the valve cover, its probably not an oil consumption issue. The tubes that go through the valve cover and surround the plug itself leak some oil sometimes and it puddles around the outside of the spark plug. Then when you pull the plug out, it runs down the threads and soaks the whole plug as it comes out. That's basically a harmless condition, although you can replace the tubes and O-rings by removing the valve cover.
A compression or leak-down test won't tell you anything useful about an oil consumption problem. Oil control rings don't seal compression (at all), they scrape oil off the cylinder walls. Compression rings don't scrape oil off the cylinder walls, they seal compression (cylinder pressure). Valve seals do not seal compression.
Originally Posted By: Scott_Tucker
A compression or leak-down test won't tell you anything useful about an oil consumption problem. Oil control rings don't seal compression (at all), they scrape oil off the cylinder walls. Compression rings don't scrape oil off the cylinder walls, they seal compression (cylinder pressure). Valve seals do not seal compression.
oil can leak past the valve seals or past worn or cracked piston rings. You can have a cracked ring and get oil consuption and low compression and have a perfect oil contol ring. Valve seals have no relation to rings
A compression or leak-down test won't tell you anything useful about an oil consumption problem. Oil control rings don't seal compression (at all), they scrape oil off the cylinder walls. Compression rings don't scrape oil off the cylinder walls, they seal compression (cylinder pressure). Valve seals do not seal compression.
oil can leak past the valve seals or past worn or cracked piston rings. You can have a cracked ring and get oil consuption and low compression and have a perfect oil contol ring. Valve seals have no relation to rings
I'm not sure if your agreeing with me or disagreeing with me?
An engine with broken compression rings will likely consume oil, that is correct. But if this is the case and the cylinders have low compression, the complaint about the engine should be 'runs like [censored]'. Oil consumption would be the least of the worries.
An engine with broken compression rings will likely consume oil, that is correct. But if this is the case and the cylinders have low compression, the complaint about the engine should be 'runs like [censored]'. Oil consumption would be the least of the worries.
OP has one spark plug covered in oil. If only one cylinder has low compression on a 6 cyl. engine, it may not be noticed by some operators.
A compression check is one tool that is used along with others to diagnose an oil burinig problem. To say a compression check is no use to diagnose an oil consumption proplem is not accurate.
A compression check is one tool that is used along with others to diagnose an oil burinig problem. To say a compression check is no use to diagnose an oil consumption proplem is not accurate.
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