Bad motor

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oLemurs
Posts: 46
Joined: Sun Feb 05, 2017 9:24 am
Car: 2005 Mazda 6, 1978 Buick regal, 1993 240sx

Bad motor

Postby oLemurs » Wed Jul 19, 2017 5:07 pm

So i just picked up this sr and the first thing i did was take out the spark plugs to see what i had, i have these spark plugs that look brand new and 2 of the 4 had a small amount of oil on the tip of them, i looked into the cylinders and didnt see anything so i turned the engine over with the cylinders out and nothing came out, what could this mean. http://i.imgur.com/WFaCHAL.jpg


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centralcoaster33
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Joined: Tue Apr 05, 2005 10:41 am
Car: 240SX #5-1997
Location: Central Coast, CA

Re: Bad motor

Postby centralcoaster33 » Thu Jul 20, 2017 12:47 pm

If I replace your commas with periods and your period with a question mark, I can kind of see a question. Can you please re-phrase your question? I'm not sure how you take cylinders out and I'm not sure what thing you expect to come out of wherever you're looking. I do see your photo but don't understand the significance of it.

oLemurs
Posts: 46
Joined: Sun Feb 05, 2017 9:24 am
Car: 2005 Mazda 6, 1978 Buick regal, 1993 240sx

Re: Bad motor

Postby oLemurs » Thu Jul 20, 2017 1:37 pm

centralcoaster33 wrote:
Thu Jul 20, 2017 12:47 pm
If I replace your commas with periods and your period with a question mark, I can kind of see a question. Can you please re-phrase your question? I'm not sure how you take cylinders out and I'm not sure what thing you expect to come out of wherever you're looking. I do see your photo but don't understand the significance of it.
there is oil on the tip of the spark plug, its kinda hard to see but when i said i took out the cylinders i mean i took out the spark plugs

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centralcoaster33
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Joined: Tue Apr 05, 2005 10:41 am
Car: 240SX #5-1997
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Re: Bad motor

Postby centralcoaster33 » Thu Jul 20, 2017 3:59 pm

Oh, okay, gotcha. Could be just a bad valve cover gasket letting oil get by. You can pull the cover and inspect the gasket or just replace it. Can you rent a compression tool and test your cylinders? That can rule out a bad piston ring letting oil get by.

The plug is pretty new and doesn't tell much of a story about the combustion chamber yet. Does the engine run?

drewsrblacktop
Posts: 11
Joined: Tue Jul 25, 2017 2:34 pm
Car: s13 sr20det blacktop

Re: Bad motor

Postby drewsrblacktop » Tue Jul 25, 2017 3:14 pm

Not sure if your saying the oil is on the top of the spark plug, or the bottom(threads). If oil is on the top its from a bad tube seal. Which is part of the valve cover gasket. Oil on the bottom (side with threads) would indicate a bad oil ring on the piston. However if that were the case the car would smoke, and burn oil. As well as have visible oil on top of the piston, and in the chamber. :crazy:


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