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I'm trying to change the engine oil but running into difficulties removing the oil drain plug. One of the instructions I followed to change the engine oil was to give the car a short drive prior to the oil change; this would heat up the oil so that it would flow more readily into an oil drain pan.

Since I am having difficulties removing the plug, I was wondering if the heat has caused the oil drain plug to expand and tightening itself to its surrounding? Is it better to attempt to remove the oil drain plug when it is in a cooled down state?

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Is this the motors first oil change ? I've run into drain plugs and filters that the factory put on really tight. –  mikes Dec 31 '12 at 19:00
    
No it isn't. I've done it before but it is being particularly stubborn this time. I was wondering if I heated it up too much and causing the stubbornness. –  Xolstice Jan 2 '13 at 23:07
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3 Answers 3

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I agree with Dan's comment - the right sized socket and a bigger bar.

I'd allow the car to cool, then using a 6-sided socket of the correct size on a 12" solid bar, crack off the seal on the plug. As with any stuck bolt, a short, sharp shock (e.g. kicking the end of the bar with your boot) is usually better than prolonged torque, which tends to be the cause of stripped heads. Once you've got it out, replace with a new, undamaged plug (and new crush washer).

I usually do my oil changes with the engine warm for the same reason you cite, the oil is a bit thinner and so flows better - particularly in the winter!

edit: As always, if you're not sure, take it to the shop - they'll do the same thing, but if they break it, it's their fault instead of yours ;)

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Very fair point on the last bit! –  Dan Jan 4 '13 at 16:13
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Are you using the right wrench? The proper wrench will not damage the plug regardless of the temperature, and if using the wrong wrench, you could be stripping the plug. If the plug is already stripped, you might want to let it cool so you can work on the problem and not burn yourself. The plug could have also been over torqued, and the heat could be adding to the issue. If over torqued, you can cool the plug while the engine is hot (Cold will shrink the plug a small amount), and allow for easier removal.

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I'm using an adjustable wrench and it is stripping the plug. I've also tried using a hex socket with no luck. I'll give your suggestion about cooling the plug a try - just place some ice next to the plug? –  Xolstice Dec 31 '12 at 9:24
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Get the engine nice and warm. Hold a icecube on just the hex part of the plug until the melting action has slowed to a really slow drip. I am assuming you know the lefty loosey, righty tighty rule:) –  mikes Dec 31 '12 at 18:24
    
Adjustable wrenches put all the torque on 2 points. Socket and box wrenches put it on 6 points. They also fit better, putting the force on the ends of the flats instead of the points. Some 6 sided wrenches even have curved faces, putting the force in the middle of the flats. –  Jay Bazuzi Jan 1 '13 at 19:15
    
The ice trick didn't help. I have a feeling that the repair shop I took my car in for the service over torqued it. I think I'll take my car in to a shop to get it removed and also have them install a fumoto oil drain valve to avoid this situation in the future. –  Xolstice Jan 2 '13 at 23:15
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@Xolstice You just need the answer to every stubborn bolt - a bigger bar and the correct socket. Don't kid yourself into thinking the shop will do anything different. I'd advise doing this while everything is cold, though. –  Dan Jan 3 '13 at 16:30
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Make sure that you're using the proper socket or combination wrench. If it's not american, it will be metric, if it is american, it may or may not be metric. There is rarely a good reason to use an adjustable wrench (usually if you need two of the same size at the same time, or you're dealing with a large size that you don't have a wrench or socket for). If you've already begun to strip your drain plug head, you can buy a new one. Also, don't over tighten it, and use a new crush washer when replacing the plug.

There are two types of sockets, 6 point and 12 point. If the head of the plug is getting stripped to the point that a 12 point socket isn't able to grip it, a 6 point socket may work better.

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