Stripped oil drain plug.. what would you do?

Any time you remove an oil pan from an engine, or inspect the sump of an engine like an aircooled VW or motorcycle, you will find sediment..... Especially in the corners or areas where the oil doesn't circulate.
The oil pickup tube is designed to draw oil up into the pump and the pan is shaped to help cup the oil around the pickup tube. Anything lower than the tube will be subject to sediment since it is not being circulated by the engine and pump. Engines with large oil capacities such as ours rely on some the oil for cooling and long oil change intervals. A lot of it ends up sitting in the pan doing nothing but sucking heat and settling out.

First, this has gotten away from the original question of how to fix his oil pan. Second, using grease as a tapping compound will work, sort of. By sort of I mean that the grease will hold the chips on the tap, which if not very careful, will cause the tap to bind because the chips are stuck to the tap in the grease and not "running up" the tap as they should. If the tap binds too hard, what will happen, it will break and then you have a much larger problem, because the tap is made from hardened tool steel which is not easy to drill and will require a carbide drill and lots of luck. There is tapping compound made for steel and cast iron, which are ferrous metals, AND tapping compound made for aluminum which is a non-ferrous metal. Don't mix them up!! When using a tap, back off every turn to turn and a half, cleaning the shavings off the tap threads and adding more compound, and take your time.
As far as drain or pump at oil changes. If you install a drain plug with a magnet on it, it will attract any metal savings that may find there way into the oil and oil pan. Slug/sediment is produced from irregular oil changes, too long of intervals between changes, in-correct oil, or an engine that is running too cold. Slug and sediment is meant to be captured by the oil filter and is removed from the engine at regular oil and filter change intervals (15,000 miles is not a normal oil change interval even when using a quality full synthetic oil, regardless of what BMW says. It just means that if you change your oil and filter every 15,000 miles, you should have no engine related wear/failures up to the 100,000 mile mark. The reason some car warranties are up to 100,000 miles is because the federal government requires a manufacturer to have all systems of a car pass at least 100,000 testing. This 100,000 mile requirement by the federal government is why there is no 1983 Chevy Corvette as the aluminumized front engine and suspension cradle and transverse kevlar spring would not pass 100,000 miles of testing without failing). A good oil change interval is 3,500 to 5,000 miles, changing oil and filter and using a quality full synthetic oil. If you pump the oil out with a vacuum pump thru the dip stick tube, at least once a year you should remove the drain plug (magnetic type) more so to inspect for metal on the magnetic than anything else. A vacuum pump will remove just about the full amount of oil that our oil pans hold.

I'll keep this very short. A tap is designed to have at least 4 groves down the sides. When you load up a tap with common grease, the groove collect the grease and shavings AWAY from the threads. You cut 2-3 threads....back the tap back out, clean the grease, apply more, repeat. There is No, and I repeat, No way you are going to get a significant amount of shaving into the oil pan OR have them interfere with the tap in Any way. This is the whole purpose of the grease, to keep the shavings away from the cutting threads and collect in the grooves and not inside your part that is being tapped.

I don't know how long you have been working on cars, but I would suggest gaining a little more experience before advising people...

The 100,000 mile warranty is not mandated....It is a bragging right for most Asian car manufactures. Even manufactures that give a 100,000 mile warranty only cover some of the drive train and a few components, not "bumper to bumper" because it nearly bankrupted their profits in the parts + service departments. If they don't sell parts, they don't make as much profit. http://www.thetruthaboutcars.com/200...year-warranty/

I agree, 3,500 - 5000, or even 7000 mile OCI's are safe for quality Full Synthetic oils. www.bobistheoilguy.com is a good resource for research. www.blackstone-labs.com is a good company to send your oil off for analysis to check on the condition of the engine and oil's performance with your engine.

I Hope I can help.

I've seen a similar issue with a Honda minivan, wal-mart oil change monkeys over-torqued the piss out of it and slowly pulled the threads off. We got the job of fixing it. Honda actually had a tap and a counter-sink cutter to install a steel insert into the pan, using loctite to hold it in, the drain plug then threads into that insert. Maybe you can look into getting a similar insert installed, I'm sure they're out there. This would also help prevent future issues, because the drain plug threads tightens against steel threads and the insert, although into aluminum still, has almost 2x the surface area to hold it.

A tip for drain plugs with crush washers. turn it till it stops then a slight ( 1/16th of a turn) snug is all you need usually.

I'm not an expert on this but are you talking about a helicoil? I know they are used to fix stripped spark plug threads in aluminum heads. Might work.

Good idea on the threaded insert. Its not like a helicoil. It is more like a TimeCert but replaces the whole threads. http://pedrn44.hubpages.com/hub/Oil-...ug-Easy-Repair
It would be a great repair for pans that are completely stripped or cracked in this area.

Originally Posted by Bobby330xi

Any time you remove an oil pan from an engine, or inspect the sump of an engine like an aircooled VW or motorcycle, you will find sediment..... Especially in the corners or areas where the oil doesn't circulate.
The oil pickup tube is designed to draw oil up into the pump and the pan is shaped to help cup the oil around the pickup tube. Anything lower than the tube will be subject to sediment since it is not being circulated by the engine and pump. Engines with large oil capacities such as ours rely on some the oil for cooling and long oil change intervals. A lot of it ends up sitting in the pan doing nothing but sucking heat and settling out.

I agree that oil that sits will get sediment trapped in it, however, what leads you to believe that the E46 oil pan is just a massive heat sink tub?

Also, from a straight fluid mechanics standpoint, even if the pan is a massive heat sink (dumb way to cool btw which is why I don't think it's true) all of the oil will at some point get sucked through the system. Just because the oil farthest away from the pick up tube is far away doesn't mean it doesn't eventually get sucked up and sent through the filter. The pan doesn't keep some areas stagnant and some areas in motion because, again, dumb design.

Lastly, since this discussion is totally off topic, the oil extractor is proven to get more out of the pan than draining. I myself have drained through the plug just to later suck out another 1/8 of a quart through the pan and another 1/4 quart through the OFH. Trying it the other way around, not one drop comes out of the plug when you use the extractor first.

If you are worried about oil settling out or sludge, your engine has more problems. Change the oil every 7500-8k and you'll be fine.

Now we are way off topic, but I'll bite.....keep trolling.

Basic automotive engineering shows that manufactures have found that increasing the oil capacity both improves the ability for the oil to keep the engine cleaner (through volume) and keep the engine cooler by extra capacity. More oil = less absorption of heat and faster dissipation of heat. VW, several motorcycle and small engine designers found increasing the oil capacity would help make an already stressed aircooled engine run cooler and live longer. They increased the oil capacity from 3 quarts to 4 from the Type 1 to Type 2 engine. I designed and built a 2270cc engine for one of my VW's that uses a "full flow" oil system that pumps all of the oil out of the engine, through the filter and back into the main galley. This way my engine is not circulating the same junk through a screen. It lowers the oil temp by 30F+ with no added coolers.
Water cooled engines can have contaminants from the cooling system, head gasket, etc. contaminate the oil in addition to the other internal parts which leave steel, iron, zinc, etc. This will show up in an oil analysis.

The oil pan is quite large in our XI cars to hold the ~7.5Qts capacity and being made of aluminum makes it a giant radiator of heat, despite not having fins. Most cars have a small steel pan that holds 3 - 5 quarts, if they have an oil pan at all.

Hmmm...I'm going to side with Sammy on this one. The BMW pans I've seen weren't loaded with sediment.

I picture the oil sloshing around quite a bit in the pan, not a quiet pool of oil waiting to be pumped back up.

Originally Posted by Kubica

Hmmm...I'm going to side with Sammy on this one. The BMW pans I've seen weren't loaded with sediment.

I picture the oil sloshing around quite a bit in the pan, not a quiet pool of oil waiting to be pumped back up.

Exactly.

Even if there were "dead" spots in the pan where sediment could collect, just driving the car would be enough to slosh the oil & sediment around such that it all eventually makes its way through the filter.

Originally Posted by Bobby330xi

Basic automotive engineering shows that manufactures have found that increasing the oil capacity both improves the ability for the oil to keep the engine cleaner (through volume) and keep the engine cooler by extra capacity. More oil = less absorption of heat and faster dissipation of heat. VW, several motorcycle and small engine designers found increasing the oil capacity would help make an already stressed aircooled engine run cooler and live longer. They increased the oil capacity from 3 quarts to 4 from the Type 1 to Type 2 engine. I designed and built a 2270cc engine for one of my VW's that uses a "full flow" oil system that pumps all of the oil out of the engine, through the filter and back into the main galley. This way my engine is not circulating the same junk through a screen. It lowers the oil temp by 30F+ with no added coolers.
Water cooled engines can have contaminants from the cooling system, head gasket, etc. contaminate the oil in addition to the other internal parts which leave steel, iron, zinc, etc. This will show up in an oil analysis.

The oil pan is quite large in our XI cars to hold the ~7.5Qts capacity and being made of aluminum makes it a giant radiator of heat, despite not having fins. Most cars have a small steel pan that holds 3 - 5 quarts, if they have an oil pan at all.

No trolling, just a discussion.

I agree with all of your points and I think I misunderstood your previous posts. The way I understood it was that the oil pan was just a massive heat sink and that's what performed the cooling. Now that you've clarified that as the oil is pumped through the engine, the cool effect is realized. Completely agree. Also, completely agree that the oil can pick up contaminants while being routed through the engine. Also agree that these can settle out in a stagnant pool of oil.

Now the "but" portion. The oil isn't stagant at all. As others have said, it sloshes around as you drive. Also, the oil pump and pump return are on opposite sides of the pan. The pump would have to go through all of the oil in the pan before getting to the freshly returned oil in a stagnant situation. In a sloshing situation, it would all get mixed together and nothing would settle out before getting pushed through the filter anyway.

While the aluminum pan is great for heat dissipation, I'm guessing that it was more for weight savings this time around. With the volume of oil to be cooled and the underbody panels not providing a complete flow of air to the oil pan, I'm not sure it would do much to cool. You are correct in that the sheer volume of oil helps the matter of cooling as well as the getting dirty part. Apparently oil temps weren't an issue otherwise the cars would have been fitted with a dedicated cooler.

Originally Posted by SamDoe1

Now the "but" portion. The oil isn't stagant at all.

SNIP!

XI oil pans



....You were saying?

Have fun "sloshing" the oil around with your windage trays and other devices that are designed to keep the oil in the pan, as I stated long ago.

I am trying to teach you people something, not just hear myself talk. I have seen literally 100's of oil pans and sumps of all makes and models that look exactly the same.

^ Why were those pans pulled? First one appears to be varnishing, second is sludge. I'm not saying that it's impossible to happen or that it won't happen. Just that if it is happening, you have an issue or haven't been changing oil/filter at the proper intervals like the ones you posted.

I understand and respect the fact that you've seen hundreds of oil pans but as long as the oil is changed properly at appropriate intervals, you won't have an issue.

Also, we started this discussion on extract vs drain. With both of the pans you posted, neither would have been prevented if you drained vs extracted or the other way around.

Those are just random images I pulled off of Google to show you that the XI pan is no different than others, in regards to sludge/varnish buildup.
The first pan is actually for sale for $289
A simple search on google images of "BMW Xi oil pan" will show 100's of similar ones.

Draining the oil with the engine warm will help flush the contaminants. It would take several oil changes with M1 or similar oil with detergents to help clean a nasty pan like the one in the 2nd pic. Just make sure you run the oil longer than 2500 miles because changing the oil too often is just as bad as not changing it enough (improper break in).

I didnt know that using tap and die sets are that hard lol, plug it in the hole and twist rofl.... Either way, Good Luck OP!

Bobby330xi, if you were referrign to my post, lets just say that I'm a certified master tech AND a Journeyman Tool and Die Maker, besides having an electrics engineering degree, that is retired from a Major OEM supplier to the automotive and truck industry, having spend 23 years as the Lead Prototype and Tooling Developer. There are 3 types of taps; 2 grove, 3 grove and 4 grove. Grease IS never used as the proper lube to cut any threads in ferrous or non-ferrous metals. There is liquid tapping compound specially made for either ferrous tapping or for non-ferrous tapping. With the proper lube, the groves are there to help guide the chips up the tap and away from the area being threaded, however, you still need to back the tap off, clean the chips off, re-lube and then cut another 1 to 3 turns, repeating until the entire thread is cut. You actually think that a CNC machine uses grease to keep the tap lubed when holes are threaded on/by a CNC mill or lathe? THe correct taping compound liquid is sprayed onto the tap, the CNC machine tapping program set to back out and then continue and this cycle repeated several times depending on the thickness of what is being tapped.
A Heli-Coil or a Keen-Sert could be used, however, they both required tapping and then using a special tool inserting the threads (not sure I would recommend a Heli-Coil for the oil pan, a Keen-Sert is much better).
On a different note, an oil pan will get some lacquer build up, especially if longer oil and filter change intervals are used and if a slightly poorer grade of oil is used. Sludge will be formed again for the same reasons. Sludge can also be a by product of an engine that is running too cold, i.e., the engine never gets completely warmed up to burn off the moisture that gets into the oil just from the changes in the weather.
And when a new vehicle IS prototyped, which can take up to 6 years from concept to sales floor, just about every part of that vehicle has to pass testing that is equivalent to 100,000 miles. Can you buy a 1983 Chevy Corvette? Do you have any idea why there was no model year 1983 Corvette? THe reason is that the aluminumized front suspension and engine cradle for the kevlar transverse front spring the GM engineers wanted to use, failed at much less than 100,000 miles. How do I know this, I was completely involved in the prototype work of that car and it was in the prototype stage(s) for 6 years.
I may not know it all, and then, NONE of us do, but please don't think that I have little to no knowledge in wrenching, machining, welding, tool and die making and electronic design and repairs. Granted, I'm not as well versed on some of the particulars of the E46s as I've only owned 2 for the last year after having/still owning quite a few E30s (at one time 5 all at the same time).

(a correction to mis-spelled word(s); electronics engineering degree

Um, what happened to the OP? I'd like to know if the poor devil ever fixed his leak?

tomoyer & Bobby330xi, let's wrap up the sword fight as you're both experienced and well qualified.

Signed,

White_Knuckles P.E., E.E., M.E. E-I-E-I-O

White_Knuckles, I agree, what did happen to the OP and did he resolve his stripped drain plug problem. I will not belittle anyone like Bobby330xi did me, however, I will correct someone if the procedure they are using isn't the correct one or the best and safest one. Ask any Machinist, Tool & Tie Maker or top notch Auto Tech and they will tell you that you do not use grease as a tapping agent/lube for any ferrous or non-ferrous metal (also stated in the Machinist Hand Book). And as I stated, there are 3 kinds of pointed taps; 2 flute, 3 flute and 4 flute, besides 2 flute, 3 flute and 4 flute bottom taps, and the same 3 types of pulley taps.

Tomoyer,

As a typical engineer always does, you are over thinking the problem. I am familiar with cutting fluids, for both ferrous and non-ferrous metals. The only time I find the need for cutting fluids is when drilling or tapping tool steel, chromalloy or another hard/brittle metal.

Referring to how a CNC machine drills and taps a hole is NO comparison to a person at home repairing a stripped hole.
A person at home tapping threads by hand will have almost no benefit by using the "correct" cutting fluid. Only light lubrication is required. If you want to keep the shavings OUT of the engine, using the 'correct' fluid will actually be detrimental since they are not designed to collect the shavings. This is why I prefer grease.
In fact, I normally use 3-in-1 oil or Marvel Mystery Oil for drilling or tapping at moderate speeds by machine.
I won't get into how long I've been working on engines (since age 5) or building them, but I can assure you this: No amount of college education, certifications or scholar is a replacement for hands on experience. I've hired and had to work with both types of people. The best employees and technicians have hands on experience over credentials. I won't even get into what I think of "engineers" being that I was paid to repair their mistakes once the product was already put into production.