stripped / rounded oil plug, safely fixed.

[Rajmun340]

This page will help you if you have a rounded oil plug. It's a 6 mm hex, torque spec is 25 NM which is low and very easy to over tighten and round the hex bore made from aluminium, not steel. This is so that the plug breaks before stripping the oil pan, but bmw design is a fail since some people have stripped the oil pan too (if so you have to "time sert" the oil pan). But here is the best way to remove a rounded oil plug.

Oil plugs should be replaced every oil change due to their fragile nature. Mine was overtorqued by the dealer which i noticed on the next oil change which i did myself. I had to employ force to remove it and ended up rounding it. Had the dealer used a torque wrench it would not have happened. (Btw, I have a pristine TDI (snap on oem manufacturer) torque wrench 10-60 N.m for sale. It's never been used and sat in its box because i bought two, and only use one. It's a high end brand, not a big store cheapo).

There are 4 ways to remove a rounded hex screw. I'll start with the bad ones. You can skip directly to next paragraph for the best way.
First solution, grinding disc and screwdriver, not applicable when the screw is counter sunked, and a poor approach.
Second way is buying a regular $3 extractor bit and a $3 drill bit (diameter given by extractor bit packaging). Drill a hole then insert the extractor with a drill machine in reverse. This is not a good solution either. The hole would have to pass through the plug because of the long angles on the extractor and may leave metal shavings in the oil pan. Worse, the extractor (which is quite narrow) could break and be stuck in and then you have a much worse problem.
Third way, getting a 7 mm hex bit (slightly bigger) or better a torx bit and tapping it into the rounded plug with a hammer. Then remove. I don't like that approach because hammering runs the risk of compromising the oil pan (aluminium).

Here the fastest, safest and still cheap way I found.
Buy a "Speed Out Titanium Screw Extractor", here



It has 4 bits, you only need the largest one. It is relatively inexpensive. If you look for it on shelves keep in mind that the plastic packaging is bulky and oversized and don't expect to see the black box, it's not visible under the carboard branding, you'll only see the 4 bits.

It's a conic type of extractor it has a more aggressive angle so you don't have to drill through the plug. One side of the bit is a short drill and the other side is the extractor. But in fact you won't need the drill side because the rounded 6mm hex provides the perfect hole In doubt you can round it more

The only other tool you need is an ajustable wrench like this one :this



1) position and line up the biggest conical extractor vertically on the rounded plug. Here i found that the power drill chuck was useful (even without drilling anything) to maintain a good vertical (upward). Of course you can power the drill but you get better control using the adjustable wrench manually (at step 2) and don't run the risk of walking the bit. Insert the extractor as little as possible inside the drill chuck (to keep sufficient clearance for the wrench to grab the hex part of the bit. Keep in mind that as you turn the extractor digs deeper into the plug and clearance diminishes) . My rounded plug was in the front oil pan which has a front bridge making you loose some clearance. In this first step you are not trying to extract the plug, only prime the rounded plug with the extractor to get a good initial and vertical grab. Then just remove the extractor without the plug by rotating clockwise. Do not try to remove the plug just yet.

2) Now, remove the extractor from the chuck and only use the adjustable wrench with the extractor. The wrench will be horizontal, it won't take more than 3/4 turn for the extractor to dig into the plug before it gets stuck in. Keep applying gentle force.

2) slowly (don't jerk or hit the wrench) torque the wrench to loosen the rounded plug. The pictured wrench is able to provide plenty of torque. Plug will break out with a pop.

It took me less time to do it once i had these simple tools than to write this page. This page would have saved me time searching how to do it. Fortunately, i tried the fastest, easiest and safest method first.

[Scharbag]

Thanks for sharing. I disagree that you need to replace pan plugs every oil change. They are not fragile. Make sure your 6mm hex key is in good shape and they will last. I set my torque wrench to 23Nm and have never had to replace the plugs. And I have done likely 6 oil changes on my M3.

And I would question the pan plug having aluminum in it. Magnets readily stick to all parts of the pan plug. Are you sure there is aluminum in there?

Cheers,

[pbonsalb]

My original oil pan plugs were fine on my 08M3 when I replaced them with magnetic ones a few years ago. The car had at least 75k miles at the time and at least 10 oil changes. I changed the plugs only because I wanted to try magnetic plugs. But if you have suffered from hack mechanics working on your car, your plugs’ hex sockets could be stripped or partially stripped.

[Rajmun340]

Originally Posted by Scharbag

Thanks for sharing. I disagree that you need to replace pan plugs every oil change. They are not fragile. Make sure your 6mm hex key is in good shape and they will last. I set my torque wrench to 23Nm and have never had to replace the plugs. And I have done likely 6 oil changes on my M3.

And I would question the pan plug having aluminum in it. Magnets readily stick to all parts of the pan plug. Are you sure there is aluminum in there?

Cheers,

Well, the S65 engine crankcase and beplate are a die cast made from aluminium alloy made by Rheinfelden, Germany. The oil pan which attach to the bedplate needs to have the same thermal expansion coefficient. If it were cast iron it would create structural tensions. The oil plug material, steel or not, needs to be soft so it gets rounded before stripping the oil pan. It is fragile by design. And the 6mm hex bore is probably chosen over more robust geometries so it rounds when over torqued. 25 NM is not much. It probably rounds at less than half the torque of wheels especially with a bad hex bit (and there are a lot of those in big stores).

[Rajmun340]

Originally Posted by pbonsalb

My original oil pan plugs were fine on my 08M3 when I replaced them with magnetic ones a few years ago. The car had at least 75k miles at the time and at least 10 oil changes. I changed the plugs only because I wanted to try magnetic plugs. But if you have suffered from hack mechanics working on your car, your plugs’ hex sockets could be stripped or partially stripped.

sloppy mechanics taking shortcuts at dealerships are more common than one thinks. Often small damages are undetected but they add up over time.

[tdott]

60k and 6 yrs, I still have the same drain plugs on my car and they are perfect.......because I've done every oil change myself.

[Rajmun340]

Originally Posted by tdott

60k and 6 yrs, I still have the same drain plugs on my car and they are perfect.......because I've done every oil change myself.

Perfect and nice wheels, paint combo.

[MahiC]

Another classic way to get a hex out is to find a torx head that is slightly bigger than the hex, then hammer the torx into the hex, and you should be able to turn the bolt. This has worked for me most times in a pinch.

[Rajmun340]

Originally Posted by MahiC

Another classic way to get a hex out is to find a torx head that is slightly bigger than the hex, then hammer the torx into the hex, and you should be able to turn the bolt. This has worked for me most times in a pinch.

Yes, it's #3 in the OP. As said, it's slightly less safe since you're hammering against the oil pan thread but hopefuly only the plug shoulder. Either way, an oil pan is die cast very thin walls any kind of hammering could set you up for future stripped oil pan. But i know that's the first thing a dealer tech will try, it's not their car and it saves them 5 min.

[Scharbag]

Originally Posted by Rajmun340

Well, the S65 engine crankcase and beplate are a die cast made from aluminium alloy made by Rheinfelden, Germany. The oil pan which attach to the bedplate needs to have the same thermal expansion coefficient. If it were cast iron it would create structural tensions. The oil plug material, steel or not, needs to be soft so it gets rounded before stripping the oil pan. It is fragile by design. And the 6mm hex bore is probably chosen over more robust geometries so it rounds when over torqued. 25 NM is not much. It probably rounds at less than half the torque of wheels especially with a bad hex bit (and there are a lot of those in big stores).

The steel pan plug will always win against the aluminum oil pan. Many people have had their pans stripped due to over-torque. The S65's steel pan plug is not designed in any way to save the pan by stripping first. A proper 6mm hex socket will not round out the plug easily. Unfortunately, there are a lot of very cheap hex sockets out there that will.

Cheers,

[Rajmun340]

Originally Posted by Scharbag

The steel pan plug will always win against the aluminum oil pan. Many people have had their pans stripped due to over-torque. The S65's steel pan plug is not designed in any way to save the pan by stripping first. A proper 6mm hex socket will not round out the plug easily. Unfortunately, there are a lot of very cheap hex sockets out there that will.

Cheers,

Not a chance, that is incorrect. I use a top of the line Williams 6mm hex socket. The dealer tech who compromised the plug on my car, did not strip the oil pan thread, but my Williams hex socket rounded the plug. And yet, after extracting it, the oil pan thread is totally fine. Which proves point blank that you are incorrect on your assertion that the plug "always" wins over the oil pan. False, it did not. All steel aren't equal, softer steels have their application by design, as in this plug. You don't seem to appreciate why it's preferable to loose a couple of bucks on a plug over replacing a several hundred dollar oil pan. It's called a sacrificial part, by design.

And there's more, materials strength isn't everything, choosing a 6mm bored hex on a M12 screw means a reduction in forces, unlike a hex head which is larger in diameter than the thread would multiply the forces on the thread. That is why a bored drive was chosen. Furthermore not torx, or star but an undersized hex bore.

i had read people's thread on stripped oil pans before writing this page. A dealer tech with an impact tool trying to cram more customers in his schedule can do that (no torque wrench either). Impact wrenching is not hand wrenching. but I am done with you, not interested in saving your ego, the technical evidence was already there on the OP.

[Scharbag]

Originally Posted by Rajmun340

Not a chance, that is incorrect. I use a top of the line Williams 6mm hex socket. The dealer tech who compromised the plug on my car, did not strip the oil pan thread, but my Williams hex socket rounded the plug. And yet, after extracting it, the oil pan thread is totally fine. Which proves point blank that you are incorrect on your assertion that the plug "always" wins over the oil pan. False, it did not. All steel aren't equal, softer steels have their application by design, as in this plug. You don't seem to appreciate why it's preferable to loose a couple of bucks on a plug over replacing a several hundred dollar oil pan. It's called a sacrificial part, by design.

And there's more, materials strength isn't everything, choosing a 6mm bored hex on a M12 screw means a reduction in forces, unlike a hex head which is larger in diameter than the thread would multiply the forces on the thread. That is why a bored drive was chosen. Furthermore not torx, or star but an undersized hex bore.

i had read people's thread on stripped oil pans before writing this page. A dealer tech with an impact tool trying to cram more customers in his schedule can do that (no torque wrench either). Impact wrenching is not hand wrenching. but I am done with you, not interested in saving your ego, the technical evidence was already there on the OP.

Wow.

Nice to see you keeping this civil.

Cheers,

[pbonsalb]

People are very passionate about their oil pans and plugs!

[SAMM3Y]

I just use an old wine cork, Rombauer Cab. Typically, keeping it classy.

[Helmsman]

Originally Posted by SAMM3Y

I just use an old wine cork, Rombauer Cab. Typically, keeping it classy.

Way to go mate and on top reuse instead of throwing away. Very political correct, love it.

[Helmsman]

Joe, long time no see, all good?

[Rajmun340]

Hi Helmsmann, Yes and good to see you lurking around.

[Helmsman]

Guys, though I complement my kit with an extra plug and went on line: Is this a $50 plug or am I getting some version in gold quoted??

[pbonsalb]

A plug is $2.59 at ECS in the US.

https://www.ecstuning.com/b-genuine-...g/07119904550/

[Helmsman]

Originally Posted by pbonsalb

A plug is $2.59 at ECS in the US.

https://www.ecstuning.com/b-genuine-...g/07119904550/

Ha, thanks mate, online shop I visited must have messed something up...

[Scharbag]

Originally Posted by Helmsman

Ha, thanks mate, online shop I visited must have messed something up...

I got 5 for $15 off of Amazon. Then I put magnets on them.

[JRV]

Just stick to doing it yourself and setting proper torque should be just fine. Same really With any bolt, lug nut, spark plug and everything should go easy in and out. The biggest issue I found regardless or proper torque is a crusty rusty car.