HELP! Broke bolt while installing oil sensor!

[xmas63]

(And yes, I was using a torque wrench!!)

Anyway, I was replacing my oil level sensor and one of the bolts broke while torquing the nut. Any thoughts on my next action? Is there any chance that the two remaining nuts will hold the part without a massive oil leak while I drive to the dealer tomorrow morning, just under 10 miles away?)

Thank you!

[wacky]

Do you have an extractor set? Also known as 'easy outs'? They require you to drill a hole in the broken bolt and then use the tool to extract the bolt. I have had good and bad luck with these myself, depending on the application.

http://homerepair.about.com/od/inter..._extractor.htm

[xmas63]

Do you have an extractor set?

In this situation, the bolts are "fixed", sticking out from the bottom of the oil pan... The sensor slips over these bolts and is fastened by nuts that go over these bolts. (Make sense?)

[gregmm6]

I think he is trying to say that they are studs, not bolts. I wouldn't try it. It could be fine, but I don't think it's worth the risk.

[xmas63]

I think he is trying to say that they are studs, not bolts. I wouldn't try it. It could be fine, but I don't think it's worth the risk.

You're right, I'm probably not using the correct word... It's these threaded "things" that stick out from the bottom of the oil pan...

[nathancarter]

Is it Part #2 on here this picture?
http://www.realoem.com/bmw/showparts...87&hg=11&fg=10

How much of the stud is left sticking out?
The picture implies that they're just threaded in place, so if you have any threads exposed, you might try the double-nut technique to remove the old stud, and the same technique to place the new stud.

Double-nut technique: First, thread two matching nuts a short way onto the stud. Using two wrenches, tighten the nuts together on the stud (NOT against the pan). Then, use one wrench on the nut closest to the pan to turn the stud and remove it from the pan. Make sense? The nut won't turn on the stud because it is tightened against the other nut, so the stud will turn instead.

If you don't have any threads exposed, but have a good bit of the stud exposed, you might be able to rent/buy a tap-and-die kit to thread it, then remove it as described above. Or, use the bolt extractor described in a previous post.

If it's broken off down inside the oil pan... wow, you might be in trouble.

Make sure to let us know how it works out...

[xmas63]

Is it Part #2 on here this picture?
http://www.realoem.com/bmw/showparts...87&hg=11&fg=10

How much of the stud is left sticking out?
The picture implies that they're just threaded in place, so if you have any threads exposed, you might try the double-nut technique to remove the old stud, and the same technique to place the new stud.

Double-nut technique: First, thread two matching nuts a short way onto the stud. Using two wrenches, tighten the nuts together on the stud (NOT against the pan). Then, use one wrench on the nut closest to the pan to turn the stud and remove it from the pan. Make sense? The nut won't turn on the stud because it is tightened against the other nut, so the stud will turn instead.

If you don't have any threads exposed, but have a good bit of the stud exposed, you might be able to rent/buy a tap-and-die kit to thread it, then remove it as described above. Or, use the bolt extractor described in a previous post.

If it's broken off down inside the oil pan... wow, you might be in trouble.

Make sure to let us know how it works out...

Nathan, thanks for your thorough reply! Yes, it is part #2 on the diagram---I just found this diagram earlier today and with this, learned that the stud is a replaceable part! I'll be picking up a replacement stud tomorrow morning from the dealer, and will (hopefully) extract the broken stud on Wednesday night. I don't recall exactly how much of the stud is sticking out---hard to say if two nuts will fit; it will be definitely be close! (I'm also going to pick up a bolt extractor just in case I need it.)

I'll let you know how things turn out! Thanks again.

[xmas63]

Make sure to let us know how it works out...

Well, here's what happened. No luck in removing the stud. There was just enough room to fit two nuts on the stud, but this didn't work because the threads on the stud stripped. I tried using a vice grip, but couldn't get a good enough grip, even after attempting to file flat surfaces onto the sides of the stud. Finally, I tried drilling a hole in it so that I can use a bolt extractor, but this was also very difficult---space under the car (on ramps) is tight and even with perfect vision, it's hard to focus on an object that's inches from you face... the hole started going off-center...right before the drill bit broke!

Bottom line is that fvcker's locked in there real tight, and clearly, the car needs to be on a lift to deal with this.

My current thinking is this:

-- Prior to yesterday's attempted repair, I had been driving the car for three days and there has been no leaks or any seepage whatsoever around the sensor. This leads me to believe that the two remaining attachment points may be sufficient by themselves.

-- I will keep a close eye on the situation and monitor for leaks on a daily basis. If there is still no problem, I'll have the dealer look at it next time I bring it in (next scheduled maintenance is in 7500 miles)

-- If the dealer can remove and replace the stud, great. If they can't and suggest that they replace the oil pan (which they have already suggested that they may need to do), I'll tell them not to, leave it as is, and continue to monitor.

Sound sensible?

[sockethead]

Most likely the factory used thread locker on the threads of the stud. You need to heat it up with a torch but you have to be really carefull because the pan is aluminum.

[MantisMan13]

Most likely the factory used thread locker on the threads of the stud. You need to heat it up with a torch but you have to be really carefull because the pan is aluminum.

You might try using a heat gun like painters use. Not as dangerous as the open flame of a torch and a bit more gradual on the heat but should get things plenty hot enough to expand the tin metal around the oil pan and the stud.
Just a thought.

[sockethead]

You might try using a heat gun like painters use. Not as dangerous as the open flame of a torch and a bit more gradual on the heat but should get things plenty hot enough to expand the tin metal around the oil pan and the stud.
Just a thought.

yep, that might work... a real heat gun. Not your girl friend's hair drier. It has to get hot enough to melt the thread locker. If it was me, I'd use a torch though

[xmas63]

Thanks guys. But at this point, I'm ready to let the dealer do it... Tired of draining the oil, etc, etc, etc...

[sockethead]

Thanks guys. But at this point, I'm ready to let the dealer do it... Tired of draining the oil, etc, etc, etc...

Ok, good luck. As clint said in Dirty Harry " a man's got to know his limitations"

[gordonian1]

I learned the hard way today that why torque specs are really important. I was changing the oil sensor on my bmw and one of the 3 threaded things/stud-bolt (which come out of the sump) snapped. So now my sensor is sitting on 2 bolts and probably might go on with a tiny leak but I would like to get it fixed regardless.


What I am wondering is, if these threaded stud-bolts coming out of sump are replaceable or do I have to replace the whole sump? looking at the blue-prints of the sump I can't find their part number (for my E91 3 serie (05-) - touring - 320i)

https://www.etkbmw.com/bmw/EN/search...22/11137568565


where as looking at this and other posts with other models of bmw they seem to be as a separate part

Can anyone help please if they are replaceable and if yes then how can I take the broken one out of the sump without having to drop the whole sump.