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DIY -Repair stripped oil pan drain plug

100K views 100 replies 52 participants last post by  gzig5 
#1 · (Edited)
Standard tools needed:

A metric socket set including ratchet wrenches, extensions, 10mm and 13mm (6pt. preferred) sockets
Everything you'd need to do an oil change (drain pan, new filter/o-ring/copper washer, oil)
Lift/low-profile ramps/hydraulic floor jack & two jackstands
Flashlight/shop light
Phillips #3 screwdriver
Power drill
~1/8in drill bit
Cleaning solvent (gasoline etc.) and cloth rags
Latex gloves
Fresh razorblade

Special tools needed:
1/4in drive 10mm (6pt. preferred) deep socket (for one tricky oil pan bolt)
Tap wrench capable of holding 1/2in taps...bar style preferred.

Timesert kit #1215C from www.timesert.com or eBay
Compressed air
Spray silicone or other lubricant
Micro torque wrench capable of 2Nm-10Nm (17.7lb/in-88.5lb/in) www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=2696
Standard torque wrench capable of 25Nm

BMW parts needed:
11-13-1-407-532 Lower oil pan steel gasket
12-61-1-744-292 Oil level sensor gasket ring

BMW parts strongly suggested:
07-11-9-903-199 Oil pan drain plug
If your pan threads were abused enough to fail your bolt threads are now suspect. A new plug is ~$3.

BMW reference part #'s:
51-71-8-195-383 Circlip
51-71-8-218-323 Screw plug
These two parts are the underbody panel securing screw and metal clip that secures it to the plastic panels. One of mine was missing from the front panel. Just mentioning it in case you find any of yours missing. Note: The metal clips on the car that these screw into are a different part number.


Who this DIY is NOT for:
If you do not know how to get the front end of you car in the air securely, do an oil change, or cannot follow the steps shown in first 4:45 of this video YouTube - TIME SERT then I suggest not attempting this DIY. Pay a shop or pay BMW!

Lets begin!
Get the front of your car securely in the air!

Remove the front underbody panel with your Phillips #3 screwdriver. The rear edge of the front panel is actually held up securely by the front edge/plugs of the rear panel (confused yet? :S). To separate the two panels you only need to undo the screw plugs that connect the two panels. The rest of the rear panel plugs can stay tight...that panel stays on the car. There are a few other plugs running along each side of the front panel that must be loosened as well. The front edge of the panel is just pressure fit into the bumper. With all of the correct plugs loosened you can wiggle the rear end of the panel free, angle it down, and rock it back and forth while pulling towards the rear of the car. It will eventually pop out of the bumper.

Drain your oil and install a new oil filter and rubber o-ring on the cap. The torque on the plastic oil filter cover is 25Nm max. Says so right on it. :hihi:

Now remove your lower oil pan. You'll want your motor to be relatively cool for this to be sure the bolts come out safely and the pan can't warp.
Remove the connector to the oil level sensor first of course.
There are 25 bolts (3 different lengths) that require a 10mm socket and a 3" extension. I used the 1/4in 10mm deep socket on these bolts mainly because of the one "tricky" bolt installed by the larger side bolt that some owners use to drain their oil. 3/8th in. or wider 10mm sockets will cause you to angle your wrench on this bolt. No reason to risk rounding this bolt off for the sake of a $6 socket. Get one.

Do not worry about the 3 different length bolts. I have a picture for reinstallation later. No sealant or RTV is used here. All you will find is a metal gasket. Confirm that it matches the part BMW gave you and then discard it. It is NOT reuseable. Pictures later will show why.

Find a clean, bright workspace and get yourself situated. I recommend sitting unless you prefer 30 minutes of being hunched over. Use an old towel to soak up lubricant (I used spray silicone) and metal shavings.


Now basically do what the first 4:45 of this video shows you using my tips. http://www.youtube.com/watch?v=Gxnm8J9WXz8

Timesert tips:
1). Old thread removal.
Not pictured is a cordless drill. I finally used that to drill out the out old threads...the tap wrench works for the other steps.
I tried using the supplied drill bit (31/64ths) in the tap wrench, but I couldn't get it to bite correctly in the drain hole. And it's tricky to use a drill because drills have 3 "jaws" and all of these bits have square heads making the bit tighten off-center.
I improvised with a 12mm 12pt. socket mounted on a hex socket driver (timesert.com suggestion). A little wobbly as you first enter the hole, but it works. I'm sure there's a proper extension (hex nut driver?) to mount a square bit in a drill, but I don't have one. If you can get one I strongly suggest it! If you ask me Timesert should source a drill bit with a normal end on it.
Who drills with a tap wrench? ouich

2). Counterboring.
Notice in the Wurth video that if you use the counterboring tool as directed the insert will not sit flush, but recessed slightly. Turns out the copper washer and the insert overlap each other as seen here:

I placed the washer and insert together as they would be when the work was finished. I decided (needlessly?) to counterbore just shallow of the depth the tool would go so that the insert would be flush with the pan. Just to be clear the inserts "collar" still seats within the recess the tool makes. All I did was make the recess just a bit shallower than the Wurth video. I wanted to make sure the crush washer seated flat and didn't have to "bridge a gap", bend, and possibly leak. Worked for me, but probably would have been fine if done normally. YMMV.

3). Tapping the new hole.
Keep shavings to a minimum while tapping the new hole using a shot of compressed air or the silicone spray. The video suggests removing the tap every new turn or so, cleaning out the shavings, and then going back in with the tool. For fear of cross-threading I decided to just blast the shavings out once per turn with air/silicone. Be sure to tap in very far. The tip of the supplied tap has a taper...you want to make sure to tap a cylindrical hole! To do this tap until the tapered end is well past the inner edge of the drain hole.

4). Installing the insert.
You can test fit your insert (for depth) with the supplied installer tool. Just don't turn it in with any force once it seats or it could get stuck! The new threads you cut in the pan do not need lubricating, but the inner threads (the ones the tool go into) do need it! Remember the installer tool expands the last 3 threads of the insert firmly into the drain hole. Without lube the threads could deform during installation. Not good because by then the insert would be locked in place. Also drive the insert tool far past the inner edge of the drain hole to make sure the 3 threads expand fully.

5). The notch.
The insert covers the drain notch up. Easy enough to remove with a drill and 1/8th in. bit. A bad angle for a drill so a thin file or grinding wheel may be a better choice if available.


Insert installed!


Now you get to put the pan back on the car!

Start by cleaning the mating surfaces of the lower oil pan AND the upper oil pan. I didn't take before shots, but rest assured before cleaning there was way more black "schmutz" on the edge here.


I used a combination of a rag dipped in gasoline and a new "square" razor blade. The razor was just to knock down the high spots of the schmutz. Don't go crazy you won't get it all off unless you REALLY like scrubbing. You don't want to scratch the surfaces either! The goal is just to have mostly flat surfaces. Be sure to now thoroughly rinse off your oilpan to remove metal shavings, gasoline, silicone etc. Very important.

At this point I reattached the oil level sensor, but you could also do it after you reinstall the pan. Use a new gasket of course. The inner edge of the gasket has little tabs/wings on it. When I took the old one off the tabs were compressed and not visible. When I pushed on the new one they wouldn't "hide." At first I thought I was doing something wrong, but then I realized there's no wrong way to put on this gasket.
Reattach it to the pan using two steps. First is to 2Nm(17.7lb/in)...second is to 10Nm(88.5lb/in). I'm assuming this is to get the gasket to go perfectly flat. I believe this gasket should also be lightly oiled prior to install as per TIS.


Here's a shot of the old and new oil pan gaskets. Notice the "rib" running along the center. This compresses and gives you the proper seal hence the old one should not be reused.



With the oil sensor installed and gasket resting on the pan slide under the the car with your 25 bolts, microtorque wrench, 3in extension, and 10mm deep socket. Notice the 3 lengths.


IIRC the four LONGEST ones go here:


IIRC the three MEDIUM ones go here:

Notice the orange label on the car. This is the rear of the pan. Drain bolt recess just barely visible bottom left.

The remaining short bolts fill in the rest.

Note: Not long from now I will be unable to edit this post. If for some reason I'm remembering the bolt locations wrong just remember that the longest bolts are TOO long to go into any holes besides their own. If you meet resistance with about a 1/4in of bolt shank visible you've put a long bolt into a medium bolt hole. Any other mismatches will be visually obvious or impossible to get the threading started.

Fingertighten them all FIRST (this helps confirm the right bolts are in the right holes) and then start tightening with the microtorque wrench.
I decided to tighten them in a plus pattern (one rear, one front, one left, one right) and then repeat using the next bolt on each side until they were all tight.
I started at 5Nm (44.25lb/in) and completed the "+" pattern.
Then I repeated the pattern with 10Nm (88.5lb/in).

Just remember that 25 (bolts) / 4 (the "+" sign torquing pattern) will leave ONE LONE BOLT on one side...a remainder so to speak. Don't forget about it! This pattern and torque stepping may be overkill, but why not right? To fix this leak later might require wasting ~$50 on 7 quarts of oil and buying a new ~$30 oil pan gasket!
The reason for the 1/4in. drive 10mm deep socket is for the one "tricky" bolt near the large side drain bolt. Using this style socket gives you the ablity to come straight at the bolt and get the right torque applied.

Reattach the wire to the oil level sensor.

Install the new drain plug and copper washer to at least 23Nm (17lb/ft). Without fear I might add.


I filled the sump 2 quarts at a time while checking for leaks at the drain bolt, oil sensor, and steel gasket. If you are as lucky as me you'll find no leaks. If you do a little more torque will probably stop it. Just remember almost everything is aluminum!

Reinstall the front underbelly cover.

Get the car off your lift/ramps/jackstands.

Fill oil sump with at least 6 or 7 quarts and then get the proper level by following the standard BMW procedure (starting/idling/stopping motor/waiting etc). I personally needed almost 8 quarts because my oil pan was loose or off for 7 days as I waited for tools and parts to arrive.
During that time almost a full quart of normally "hidden" oil managed to leak out in spurts every 1-2 days. Probably the VANOS accumulators etc. discharging plus a few other places oil normally doesn't drain from during a 10 minute oil change. Keep your drain pan under the car whenever the lower pan is loose or off the car. And also anytime you have the drain bolt removed.

Start the car and confirm the oil level warning light goes out. If not check the oil level and make sure your oil sensor is plugged in properly.

You...are...done! cherrsagai
 
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#8 ·
Agreed.

Just don't forget all the time it took TMcNasty to document this. I've done similar tech article postings on other message boards and it's very time consuming to be detailed and organized like TMcNasty has been here. He gets a big thumbs up for taking the time to document this in a very detailed manner. :applause:
 
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#4 ·
Who this DIY is NOT for:
If you do not know how to get the front end of you car in the air securely, do an oil change, or cannot follow the steps shown in first 4:45 of this video YouTube - TIME SERT then I suggest not attempting this DIY. Pay a shop or pay BMW!
kind of an oxymoron isnt it? a diy for how to fix the oil plug after you fail to properly change the oil....:haha2:
 
#5 ·
I was thinking of all of the related tasks you'd need to know already that I just wanted to glance over (raising the car, doing an oil change, etc.). But from that perspective you're right on!!! I admit I chuckled out loud!

Yeah if you can't handle changing your oil you may not want to go at your $400 oil pan with a power drill. LOL. ;)
 
#6 ·
Nice job. The oil pan gasket goes on dry? No sealant of any kind? I usually smear a thin layer of sealant on the mating surfaces, and unless the TIS specifically says not to, I don't think it would hurt. You might have to wait for it to set before you fill it up with oil though.
 
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#9 · (Edited)
The oil pan gasket goes on dry? No sealant of any kind? I usually smear a thin layer of sealant on the mating surfaces, and unless the TIS specifically says not to, I don't think it would hurt. You might have to wait for it to set before you fill it up with oil though.
I know how you feel xr4. I was a highly skeptical myself. Thought for sure I'd be redoing this with RTV even though no RTV was used by BMW at the factory. I even asked at my dealer when I picked up the parts. Even they said no RTV.
Bottom line is these parts are milled perfectly flat and that rib on the new gasket does its job. I had the underbody trays off for a long time after the refill. Not even a hint of a leak.
I'm sure TIS will confirm no RTV.
 
#10 ·
And I've decided to offer to repair members oil pans for a reasonable fee. Of course you'll need to ship me the pan (CLEAN and with no oil level sensor attached) and wait for it to return. I'll do it the day I get it and ship it that day or the next. See new signature below.
 
#11 · (Edited)
Very disappointing to find a small, fresh oil spot under the front of the M when I moved it today! I'm assuming something needs just a little more tightening. I guess my Chinese made microtorque wrench is set to "cautious"...I'll guess I'll have to manually set it to "careful there buddy."

:)

Will report back tomorrow.
 
#12 · (Edited)
FINALLY finished!

Turns out the oil leak was coming from JUST the repaired drain plug! :biggrin:

Took the front cover off to get a look at the oil pan gasket and oil level sensor gasket just to be sure though. No leaks there.

I had to set my torque wrench to 30lb/ft to even get the drain bolt to spin more. When that clicked over no more leaking. This time I REALLY waited...even ran the car. I'm thinking either:

1). Drilling out the insert to open up the drain notch on too much of an angle took out too many threads near the "ground side" of the insert
2). Not fully countersinking the insert as per timesert instructions (even though it is flush)
3). Having a no longer perfectly smooth mating surface for the (not very wide) copper crush washer

causes me to have to crush that washer more than I would on a brand new pan. Luckily with a steel insert I can probably go to 75+lb/ft without fear. Anyway...bear these thoughts in mind if you decide to do this repair.
 
#18 ·
Instead of using a T-bar or straight tap handle, I used 12-point sockets on the tap and counterbore, which worked better than my tap handle (I don't have a ratcheting tap handle).

If anyone is looking to purchase the kit (less one insert . . . 3 remain for our oil pans . . .). I'll let it go for $75.

Local Boston pickup preferred.
 
#19 ·
Im getting a drip from my drain plug. Im going to follow these steps but Im wondering what the general consensus of the board is of putting in a valve of some sort? Once I retap the oil pan, put in the new threads, what about putting a drain plug? That way it wouldnt get torqued wrong again and its easy access?

Thoughts?

Also, rtomlinson, do you still have the set to sell?

Thanks all!
 
#33 ·
I.... Im wondering what the general consensus of the board is of putting in a valve of some sort? Once I retap the oil pan, put in the new threads, what about putting a drain plug? That way it wouldnt get torqued wrong again and its easy access?
That's the approach i would take should I ever have to drop the pan to repair damaged threads.

This mfr seems to have a variety of quality valves made for oil draining.


OilDrainValve.net
 
#21 ·
TMcNasty: I appreciate the time and effort that went into putting this DIY together!!

Can anyone address the dynamics of how the oil system 'primes' itself during initial starting?

My assumption is that during regular oil changes the extra 1 qt of oil that the OP saw leave the system would essentially remain 'active' in providing initial start-up protection. However, if this amount drains, is there a valid concern to be had for 'dry' starting?
 
#24 · (Edited)
Sorry to revive an old thread. First off... I used the SEARCH function :) instead of creating a new thread, so hopefully I won't get flamed too much. I recently purchased my '03 M5. Since that time, I've been diligently performing maintenance on the car for my own peace of mind. I performed and oil change last weekend, only to find that the previous owner had stripped the oil pan bolt. Their fix? They used a larger bolt (wrong thread pitch and all). Of course, I promptly purchased a new lower pan, gasket, bolt, and washer to repair the previous owner's mistake.

So... To those who felt this is silly since "kind of an oxymoron isnt it? a diy for how to fix the oil plug after you fail to properly change the oil....:haha2:<!-- google_ad_section_end --> " ; This is very handy.... I'm just trying to correct a problem I inherited.


Thanks for a great write-up; I was actually searching for the torque spec's on the drain plug bolt and the lower pan bolts.


- Chris
 
#25 ·
So... To those who felt this is silly since "kind of an oxymoron isnt it? a diy for how to fix the oil plug after you fail to properly change the oil....:haha2:<!-- google_ad_section_end --> " ; This is very handy.... I'm just trying to correct a problem I inherited.


Thanks for a great write-up; I was actually searching for the torque spec's on the drain plug bolt and the lower pan bolts.

Thanks for using the search! I think many will agree that this is not a problem of "if" but more a problem of "when". I use a torque wrench every time I tighten my drain plug, but still have this thread book marked as I am fairly confident mine will leak eventually.
 
#27 ·
Time-Sert threaded bushing

When my drain plug threads met their demise, I purchased the Time-Sert kit for the repair and the result is totally
bullet-proof. With a solid, threaded bushing mechanically locked into position at both ends, plus Loc-Tite, there is
no way it will ever fail again. The outer flange of the new bushing, recessed and flush with the original surface,
provides a perfectly matched seat for the drain plug sealing washer.

Installing a new pan (for serious change), only serves to reset the clock for the next occurrence. Not to mention
the fact that the pan should have had a solid threaded bushing when it was designed.

Regards,
Alan
 
#29 ·
Probably shoudn't say this but I will anyway... I simply re-tapped my stripped drain hole with a 1/4 std pipe tap, used a 7/16 X 20 tpi bolt and an "O" ring to make the repair without removing anything. When I change the oil I always use a fresh ring and torque the screw lightly. The rubber seal acts as a locking device plus sealing the drain. I haven't had any problems. If you are afraid the bolt/plug might come out unexpectedly you can rig it with aircraft safety wire by drilling a small hole through the bolt head. Of course the above procedure is probably the correct way of making the repair.
 
#30 ·
I do my Time-Sert repair last week. It was really easy and the results were great.

However, my oil plug is leaking. I used a Magnetic type plug first with the original bronze washer.

After it started leaking, the plug was change to an original plug type.

It's still leaking a lot.

Any recommendation is really appreciated.
 
#31 · (Edited)
I used a Magnetic type plug first with the original bronze washer.

Any recommendation is really appreciated.
I'm going on the assumption that your repair went flawlessly...

The washer is copper which is pretty soft and is meant to be crushed between the pan and bolt to make the oil tight seal. They are a one-time use item. You're leaking because you reused one that was already crushed. Go to the dealership and buy and handful. Don't reuse it next time. Didn't your new filter come with a new washer?

You might be able to slow the leak (or even stop it) this time by making it tighter. When I repaired my pan I couldn't get it totally sealed until I hit 30 lb/ft even with a new washer. I just use 30 lb/ft now. No worries with the steel Timesert in place. I wouldn't dare do that with the aluminum threads!

Worst case scenario you can drain your oil into a CLEAN container to change to a new copper washer.
 
#34 · (Edited)
If the insert is leaking you might have to pull the pan and seal the insert threads with thread sealer or something. If just the plug is leaking you might try an "O" ring of the appropiate size. If it is "leaking alot" it is probably internal. Maybe the insert threads are cross-threaded. Did the insert go in easily after the pan was re-threaded for the insert or was a little force needed indicating a cross thread?
 
#41 ·
Sure you have enough posts to send PM's? I thought it took 75 posts before you can send. I didn't get a response to my PM.
 
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