Oil Pan Thread Stripped

[jagman]

After several oil changes the oil pan thread has stripped. I had it flat bedded to a shop. The owner says there isn't enough thread to do a tap. I asked about a Timesert. He said he'd do it if I asked him to but highly recommended against it for something as important as oil. I asked why and he said it could come loose while driving and I would be in jeopardy of losing the engine (and because of that risk he wouldn't warranty that it would work). He highly recommended changing the oil pan and while it's off doing the rod bearings since taking the pan off is 80% of the labor. I have 55,000 miles on my M3 so it makes sense. I asked about the Clevite rod bearings done through this forum but he suggested going OEM.

His suggestions are obviously conservative. His shop does LOTS of work on BMW race cars. He knows what he's doing. My question is... Is he just recommending that because it generates a lot of business of are his concerns legitimate? What do you guys think?

[roastbeef]

i know of two people that did a timesert that track without issues.

if you're going to go as far as replacing the rod bearings, i would definitely upgrade. no sense in doing all that just to put the same crap back in.

[Powashiftin]

Originally Posted by BeamerBimmer

How does one even strip the drain bolts?

Over tightening.

[roastbeef]

Originally Posted by BeamerBimmer

How does one even strip the drain bolts?

its becoming a very common thing.

[kamber]

Upon conducting my first oil change, I discovered one of the two drain holes in my oil pan had the threads stripped due to overtightening by the previous owner. I went with a time-sert repair after looking into all possible solutions and it's holding up excellently; I'm confident in the integrity/durability of the repair and would definitely do it again given the choice. However, my rod bearings were already changed out 20k miles ago, so our situations may differ a bit. I'd say if you're planning on having your rod bearings done and don't mind the additional cost of an OEM replacement lower oil pan, then it's a no brainer to just replace the part instead of fix it.


Details regarding my experience with using the timesert kit:
http://www.m3post.com/forums/showthread.php?t=1328740

Originally Posted by BeamerBimmer

How? Over tighten/use of impact?

I'd imagine so; it has to be either from the use of an impact gun or some other careless/improper method of torqueing the drain bolts. When I went to do my first oil change, I found the bolts to have been WAY overtorqued by whoever touched it last; managed to get them loosened and out with a breaker bar, but the oil pan threads were destroyed on 1 of the 2 drain holes.

[roastbeef]

Originally Posted by BeamerBimmer

How? Over tighten/use of impact?

people tend to over tighten them. they really don't take much.

use of an impact on our oil pan probably has a 100% failure rate.

[jagman]

Do you guys think it's best to use a torque wrench? If yes what would you set it to? I'm just trying to minimize the chances of this happening again.

Btw this happened just using a hand held socket wrench and it wasn't tightened hard but obviously it must have been too hard. I've since found BMW has a service bulletin on not over tightening it.

[doogee]

Originally Posted by jagman

Do you guys think it's best to use a torque wrench? If yes what would you set it to?

A torque wrench never hurts. 25 Nm

Some people haven't been working on cars long enough to know how much torque to apply by hand. If this is the case, always use a torque wrench.

My rule of thumb is finger tight + 1/8 turn.

[jagman]

Originally Posted by doogee

A torque wrench never hurts. 25 Nm

Some people haven't been working on cars long enough to know how much torque to apply by hand. If this is the case, always use a torque wrench.

My rule of thumb is finger tight + 1/8 turn.

Thank you