Shop stripped oil pan during oil change, stuck a larger bolt in and left it.

Helmsman wrote

Totally agree. Obviously they should repair what they destroyed. Would be worried about them doing the job though, if they even can't get a sump plug right...

It’s all pretty scary man. My local BMW is shit too! I despise bringing my car to them unless I’m backed against a wall. I just bent a tie rod last week. I get a video from my tech at BMW stating I need ti replace my steering rack, thrust arm is cracked and alignment. The fucking tech said the seem on the collar of the trust arm was a crack but it’s how the part is manufactured. I then had them replace the whole toe rod assembly. A difference of $5k or $800. People need to get behind their work or stop working on stuff.

The threads DO NOT FATIGUE over time! I’ve got 256,xxx and have performed all my oil changes myself at 5,000 mile intervals. So many oil changes that the ecu cannot recommend any more mileage intervals due to lack of memory. I have never once had an issue with the same two bolts since I bought it with 25,000 miles. I replace the crush washer every time and torque to 18ftlbs or 25nm. Not observing proper torque and or overtorquing a hot motor is what causes thread fatigue. Again, bad practices!

Scrippy wrote

The threads DO NOT FATIGUE over time! I’ve got 256,xxx and have performed all my oil changes myself at 5,000 mile intervals. So many oil changes that the ecu cannot recommend any more mileage intervals due to lack of memory. I have never once had an issue with the same two bolts since I bought it with 25,000 miles. I replace the crush washer every time and torque to 18ftlbs or 25nm. Not observing proper torque and or overtorquing a hot motor is what causes thread fatigue. Again, bad practices!

1) The threads absolutely fatigue. You've been both precise AND lucky.
2) Unless the same shop has changed the oil every single time, how can any shop accept liability for replacing the oil pan? (Again, setting aside OP's situation which is obviously unacceptable.) If one guy overtorqued it just once, it's a time bomb.

nrubenstein wrote

1) The threads absolutely fatigue. You've been both precise AND lucky.
2) Unless the same shop has changed the oil every single time, how can any shop accept liability for replacing the oil pan? (Again, setting aside OP's situation which is obviously unacceptable.) If one guy overtorqued it just once, it's a time bomb.

Agree to disagree. I once stripped a header stud bolt and it was 100% my fault. That stud didn’t strip the block itself. You do bring up a great point for OP though…..try and stay with a shop and not just go around to the cheapest option. I would highly recommend doing something so trivial like an oil change yourself to make sure it’s done correctly EVERY time. Most shops have timing issues in order to be profitable and specifics get skipped.

egebhardt wrote

Obviously he's going to contact the shop who made the mistake.

Here's Sreten fixing his stripped bolt at 12:52 into the video.

You basically are draining all the oil so there's 10 Liters possibly down the drain unless you feel comfortable pouring it back in. This can all be done under the car without removing the pan but if the guy took the shop to a shop for rod bearings, he may not be able to do this fix.

My rear plug stripped. So plan on doing this repair per the video, however, why is it so hard to find a M13x1.50 Allen Key replacement plug? Its like they aren't even made based on my search. M14s are there, but I don't want to go that large right away. TIA.

AndyW wrote

My rear plug stripped. So plan on doing this repair per the video, however, why is it so hard to find a M13x1.50 Allen Key replacement plug? Its like they aren't even made based on my search. M14s are there, but I don't want to go that large right away. TIA.

Well, the tapping and 13mm hex head worked..so far. No leak when full and cold. Just warmed it up to temp to get an oil level. Will see if I have any drips tomorrow or Tuesday. The 13mm hex head does not extend past the metal of the subframe so no real increased risk of it getting sheared.

FYI, I used the grease on the tap and it did collect a lot of metal shavings, but I also ran 2 qts of oil through it, twice. And got a good bit of shavings in the first round, and just a few tiny ones in the second. So...using the grease is *not* sufficient by itself if you do this with the pan on the car, as some guides I read implied. I am sure the oil suction screen and/or oil filter would get anything that got sucked up, but why risk it? Waste a little oil, save an engine!

Merry Christmas!

This may be too much nerdy engineering detail for you guys but you should be careful when retaping holes in aluminum. Most mechanics don't actually know this but the thread profile for aluminum threads is actually different than that for steel. Most hand taps will be for steel and will have a looser, general thread tolerance, with a shorter thread engagement, this will infact result in a looser bolt fit, and potentially leakage and further stripping. There are special taps with more precise thread tolerances.

Becareful with simply doing something that Sreten did on his YT channel. It's fine to like the guy, but he's does a lot of dirty hacks and frequently doesn't use the correct tools, despite having the means to buy the tool. Having just watched more if his videos, there are actually several things that I notices that are big NO NOs, but he does it anyway probably because he doesn't know any better.

Shops like VAC often have very low level entry level guys (grease monkeys) do oil changes and they are just as likely to fuk things up as the Walmart or Jiffy lube guy Same for dealers. The first thing these guys do is to retap the hole and take the risk that you will never know any better, and most of you will never know, which is why many of us will never let others work on our cars.

S85 builder wrote

This may be too much nerdy engineering detail for you guys but you should be careful when retaping holes in aluminum. Most mechanics don't actually know this but the thread profile for aluminum threads is actually different than that for steel. Most hand taps will be for steel and will have a looser, general thread tolerance, with a shorter thread engagement, this will infact result in a looser bolt fit, and potentially leakage and further stripping. There are special taps with more precise thread tolerances.

Becareful with simply doing something that Sreten did on his YT channel. It's fine to like the guy, but he's does a lot of dirty hacks and frequently doesn't use the correct tools, despite having the means to buy the tool. Having just watched more if his videos, there are actually several things that I notices that are big NO NOs, but he does it anyway probably because he doesn't know any better.

Shops like VAC often have very low level entry level guys (grease monkeys) do oil changes and they are just as likely to fuk things up as the Walmart or Jiffy lube guy Same for dealers. The first thing these guys do is to retap the hole and take the risk that you will never know any better, and most of you will never know, which is why many of us will never let others work on our cars.

What are some of his dirty hacks? I think he’s known for doing things the right way when possible.

oh boy, here are just a few from recent few I watched: He drives the main seals with a hammer, there is no way to keep it square like that, that is why they make a specific tool for that. I think he only has 1 or two of the actual service tools, all his hand tools are free from Hazet anyways. Same thing for the front seal but that was an ok improvise.

He has the engine completely torn down, but doesn't measure the mains and rod journals. Doesn't check for taper, flatness, and concentricity. No measurement of thrust clearance, no weighing and balancing. Didn't even pressurized the oil system before start up to get oil to the upper part of the engine. He didn't show the head rebuild up. I'm not surprised about that since there's quite a bit of intricate work and getting the keepers seated correctly isn't easy. He may have had someone else do that. There's a TON of measurement work that needs to be done there. Double sealing the orings with his paste causes issues when you have to replace those orings again.

I'm not here to bag on the guy or anyone, but your top engine builders would actually do things differently. I scratch my head since he spent more time and effort to layout all the parts for a nice picture than spending time to do the real work and measure, measure, measure. He talks about how he loves all this tedious work, but the tedious work in precision engine building is the measurement and making sure things are in tolerance. It's more than just plastigage. The fact that S65s have such a critical issue with main bearings, I REALLY can't understand not manually measuring the main bearing clearances and concentricity then fitting the bearings appropriately. He just reused a different crank, so it's not like this crank was polished and prepped by a machine shop. The assembly work is the easy part, most of the instructions are in the BMW TIS manual. That doesn't mean his engine won't run, but a proper rebuild from would involve ALOT more.

nah dude wrote

I considered doing a timesert, but larger bolt they used is an m14, 2mm larger than the OEM, and it wobbles in the existing threads so even that bolt is a little small. Seems they removed quite a bit of material already. Knowing how the bung is welded on the inside of the pan, there's not much material to begin with and I'm not sure if it's okay to remove more to do the timesert.

Time-Serts are a legit and factory approved thread repair process from many OEMs. Since this is a "frequently" used joint, it would be the most robust repair method, but you are correct in that it doesn't have the slot milled out in it to allow a complete drain like the factory bung.

S85 builder wrote

Time-Serts are a legit and factory approved thread repair process from many OEMs. Since this is a "frequently" used joint, it would be the most robust repair method, but you are correct in that it doesn't have the slot milled out in it to allow a complete drain like the factory bung.

This. We've seen many S54 and S65 pans come in stipped or very close to it and this repair has worked.

S85 builder wrote

oh boy, here are just a few from recent few I watched: He drives the main seals with a hammer, there is no way to keep it square like that, that is why they make a specific tool for that. I think he only has 1 or two of the actual service tools, all his hand tools are free from Hazet anyways. Same thing for the front seal but that was an ok improvise.

He has the engine completely torn down, but doesn't measure the mains and rod journals. Doesn't check for taper, flatness, and concentricity. No measurement of thrust clearance, no weighing and balancing. Didn't even pressurized the oil system before start up to get oil to the upper part of the engine. He didn't show the head rebuild up. I'm not surprised about that since there's quite a bit of intricate work and getting the keepers seated correctly isn't easy. He may have had someone else do that. There's a TON of measurement work that needs to be done there. Double sealing the orings with his paste causes issues when you have to replace those orings again.

I'm not here to bag on the guy or anyone, but your top engine builders would actually do things differently. I scratch my head since he spent more time and effort to layout all the parts for a nice picture than spending time to do the real work and measure, measure, measure. He talks about how he loves all this tedious work, but the tedious work in precision engine building is the measurement and making sure things are in tolerance. It's more than just plastigage. The fact that S65s have such a critical issue with main bearings, I REALLY can't understand not manually measuring the main bearing clearances and concentricity then fitting the bearings appropriately. He just reused a different crank, so it's not like this crank was polished and prepped by a machine shop. The assembly work is the easy part, most of the instructions are in the BMW TIS manual. That doesn't mean his engine won't run, but a proper rebuild from would involve ALOT more.

I've reviewed all your comments and agree with you. Given the S65's level of performance, a full "blueprint" rebuild would be appropriate and necessary. I worked at an engine rebuilding company for a year on the assembly line and very few if any of your mentioned tasks were performed on the parts. The engines we output worked fine but they were low to medium level performance engines and their prices reflected the amount of work and parts put into them.

Baba Louey

I didn't watch his whole Alpina rebuilt and how that first one failed, but I'm not surprised either. I realize he's probably doing this to get maximum YouTube views and engagement, but reading the comments is pretty sad since like 99.9% of the comments are people expressing amazement. Just weird. Like I can't fine one critical comment, which is almost impossible. Any one of Steve Papadakis' videos (renouned top race engine builder) has critique and comments.

I'm also aware that dealerships who do engine component work will do very little measurement also, I know that the book rate doesn't pay for precision measurement stuff, and that would be one of the reasons, some of the measurement specs and procedures aren't in TIS. Heck, BMW doesn't recommend or allow for decking the head or block, I understand why, but I found it a real PITA that they won't even give many of the common specs that you'd in service manuals for GM or Ford engines by way of example.

In an aluminum oil pan, all it takes is one over-torque of a drain plug and the threads will forever be compromised from there on out. Some may refer to this as "fatigue". You can buy a car at 80k miles and do three or four, five or six more oil changes perfectly and then wham...stripped drain plug.

It happens all the time and is not necessarily the fault of the tech. The correct, approved repair is a properly installed Time-sert. Without clear and provable indication of negligence it is completely unreasonable to demand a new oil pan at the shop's expense.

I do agree that this concern should have been brought up immediately to the customer with a solution. VAC's reputation is excellent and I'm sure they'll remedy it.

S85 builder wrote

oh boy, here are just a few from recent few I watched: He drives the main seals with a hammer, there is no way to keep it square like that, that is why they make a specific tool for that. I think he only has 1 or two of the actual service tools, all his hand tools are free from Hazet anyways. Same thing for the front seal but that was an ok improvise.

He has the engine completely torn down, but doesn't measure the mains and rod journals. Doesn't check for taper, flatness, and concentricity. No measurement of thrust clearance, no weighing and balancing. Didn't even pressurized the oil system before start up to get oil to the upper part of the engine. He didn't show the head rebuild up. I'm not surprised about that since there's quite a bit of intricate work and getting the keepers seated correctly isn't easy. He may have had someone else do that. There's a TON of measurement work that needs to be done there. Double sealing the orings with his paste causes issues when you have to replace those orings again.

I'm not here to bag on the guy or anyone, but your top engine builders would actually do things differently. I scratch my head since he spent more time and effort to layout all the parts for a nice picture than spending time to do the real work and measure, measure, measure. He talks about how he loves all this tedious work, but the tedious work in precision engine building is the measurement and making sure things are in tolerance. It's more than just plastigage. The fact that S65s have such a critical issue with main bearings, I REALLY can't understand not manually measuring the main bearing clearances and concentricity then fitting the bearings appropriately. He just reused a different crank, so it's not like this crank was polished and prepped by a machine shop. The assembly work is the easy part, most of the instructions are in the BMW TIS manual. That doesn't mean his engine won't run, but a proper rebuild from would involve ALOT more.

Hi. I addressed your concerns in this thread.

S85 builder wrote

This may be too much nerdy engineering detail for you guys but you should be careful when retaping holes in aluminum. Most mechanics don't actually know this but the thread profile for aluminum threads is actually different than that for steel. Most hand taps will be for steel and will have a looser, general thread tolerance, with a shorter thread engagement, this will infact result in a looser bolt fit, and potentially leakage and further stripping. There are special taps with more precise thread tolerances.

The difference between steel and aluminium taps isn't the tolerance; it's the material, flute design and finish/coating of the tap. You can buy taps of different tolerances as required by whatever spec or scenario you're dealing with, but the default fit for various materials is the same; 6H/6g. The thread profile is not different for different materials.

AndyW wrote

Well, the tapping and 13mm hex head worked..so far. No leak when full and cold. Just warmed it up to temp to get an oil level. Will see if I have any drips tomorrow or Tuesday. The 13mm hex head does not extend past the metal of the subframe so no real increased risk of it getting sheared.

FYI, I used the grease on the tap and it did collect a lot of metal shavings, but I also ran 2 qts of oil through it, twice. And got a good bit of shavings in the first round, and just a few tiny ones in the second. So...using the grease is *not* sufficient by itself if you do this with the pan on the car, as some guides I read implied. I am sure the oil suction screen and/or oil filter would get anything that got sucked up, but why risk it? Waste a little oil, save an engine!

Merry Christmas!

Well, I guess I didn't get it quite parallel...fitting leaks. Will replace copper seal with rubber and see if that fixes. Otherwise I guess I'm getting a new pan...ug.

Install a Time-sert in the aluminum pan and move on. Should they have let the owner know about the issue? Yes. Was it their fault? Who knows.

Tambohamilton wrote

The difference between steel and aluminium taps isn't the tolerance; it's the material, flute design and finish/coating of the tap. You can buy taps of different tolerances as required by whatever spec or scenario you're dealing with, but the default fit for various materials is the same; 6H/6g. The thread profile is not different for different materials.

Yes the flute design actually differs. Frequently in mass production of aluminum casting, the threads actually aren't cut, they are thread formed using special taps, no material is actually cut away, instead it's hot worked into the desired thread form this makes the thread area stronger, which is highly desirable especially in a "service joint" like a drain hole. If you take a look at the cross section and use appropriate magnification. The threads roots aren't sharp V and this makes the threads in the softer metal much stronger. Also OEMs use special bolts threads (tri-lobe) for threading into aluminum, to prevent galvanic corrosion between the dissimilar metals (steel bolt into aluminum threaded base material).

I spent alot of time in manufacturing process engineering at engine and transmission plants in an earlier life. They are certainly NOT using normal cutting tap threads.

Sreten wrote

Hi. I addressed your concerns in this thread.

This is an interesting way for you to respond. This is called brigading, inviting others to a separate website and forum to respond. I'm responding here for of others who may actually want to learn or understand, which is why I type this in an S65 area vs an X1/X2 forum. I'm not going to take your bait, I'm sure you have a rabid fan base over there, in fact I'm sure you have more fans here that I ever will. This is why very few professionals bother to comment.

I very rarely comment on forums and videos because these things turn in to debates where someone who expresses a unique or informed opinion quickly gets squashed, which is clearly what has already happened on your other thread.

I was asked specifically to comment on things that I THOUGHT were done incorrectly or sub optimally. You clearly don't care what I have to say, because you immediately dismiss professional practices and critique out of hand, that's fine.

I stand by my commentary, and I've also talked to some other engine builders (mainly Chevy guys) and they agreed. You did not blueprint the engine, but if you think you actually did, then feel free to post up your build sheet of all your measurements. You said "I measured the crankshaft, all perfect and within spec." OK bro.

Here's a fact. BMW doesn't even publish in TIS the nominal and tolerance values of most of the typical blueprinted dimensions (it's agnostic to any engine). I'm sure that Bert from BE would certainly agree. No educated builder would ever say "all was perfect and within spec" while knowing that there aren't published specs!

As for measuring bearings, this requires special micrometers, and where you measure matters, because they have a specific profile for bearing crush and elongation. You'd have to have measured both in the fully torqued in the bedplate. This is even a worse PITA than you think. Then you still don't have a concentricity measurement, with or without the bearings installed.

You said "If I were mixing and matching a different crank/bedplate/block, then for sure, proper measurements with tools are highly recommendable, but this wasn't my case." This is one of my fundamental points of engine rebuilding, you ALWAYS measure when the engine is apart ESPECIALLY on the S65 where there are well established flaws with cause bearing failure everywhere on the lower end of the engine.

As far as rebuilding of the head, did you take measurements there? what about valve tip protrusion, valve guide clearance, spring height, force. Pro engine builders all measure this EVEN WITH NEW STUFF. Did you vacuum test your cylinder head? How much vacuum were you holding? Again, there's real substance to me saying that YOUR build was suboptimal. This is easily a 1hr video by itself, but I think it would be boring AF. I use a Sunnen head disassembly bench, it's a universal machine for compressing springs, but it is production level machine, and it is still a PITA. I could elaborate on the importance of balance of the complete rotating assy, but doesn't seem like you'd not appreciate one bit of what I'd say. You new cams will be glorious, just rev rev away.

There's really no dispute in the professional rebuilding arena about using Torque plates and why, street engine or race engine. It's about all thickness and distortion. The difference is actually measurable with a bore gage.

I will watch your Alpina video but based on your explanation, YOU (the builder) specified the desired bore diameter, that actually is YOUR job as the builder. As long as they it the number within the tolerance YOU specified, they did what they were supposed to. Seems like you admit that you didn't know that hypereutectic pistons have a different coefficient of thermal expansion than forged. Tough lesson, cool that you documented, no shame there, but if you were properly educated, you'd have known, that's engines 101. That's why education matters. You also have to specify different rings when you go with sleeves. If the machine shop hit the spec you gave, then you should not expect any renumeration from them. If you then chose to defame them by insisting, they made the error then really they should be suing YOU for reputational damages.

There are many professionals who do these things for a living, you seem to infer that you KNOW they don't measure things and don't follow proper torque procedures. That's a big claim sir. That infers the whole industry does things wrong, and you know better and do it better.

You seem to know that 1% of the comments you receive are hateful or offensive. I just guessed and it seems like I'm right, it seems like you and YT want to have a bunch of happy happy joy joy positivity, while censoring any critique. Well that's kinda cool and really creepy too. I understand why they do what they do and frankly I don't think content moderation is done well as we've seen with Twitter and Facebook censorship. Congrats on doing what you like. This commentary isn't about where you came from, it's about specific things that weren't done right.

Someone else will have to explain my comment about your lack of pre-pressuring lube practices. It may very likely have contributed to premature wear on your other engines. If I say it, it will only seem like I'm preaching to you from my high horse, but it's done for a reason, and what you did isn't it.

EDIT: Oh and if anyone thinks I am Troy or I know the guy, you are seriously misinformed...

This is why I never let any shop change my M3's engine oil. Aluminum oil pan, steel bolt and a high turnover shop are just a troublesome combination.

You shouldn't always torque the bolts to 25Nm either, because oil residue between the oil pan thread and the bolt likely leads to OVER-tightening at that value. I've been sticking with 18Nm and they've held up fine for about a decade.

S85 builder wrote

Yes the flute design actually differs. Frequently in mass production of aluminum casting, the threads actually aren't cut, they are thread formed using special taps, no material is actually cut away, instead it's hot worked into the desired thread form this makes the thread area stronger, which is highly desirable especially in a "service joint" like a drain hole. If you take a look at the cross section and use appropriate magnification. The threads roots aren't sharp V and this makes the threads in the softer metal much stronger. Also OEMs use special bolts threads (tri-lobe) for threading into aluminum, to prevent galvanic corrosion between the dissimilar metals (steel bolt into aluminum threaded base material).

I spent alot of time in manufacturing process engineering at engine and transmission plants in an earlier life. They are certainly NOT using normal cutting tap threads.

You can get thread forming taps for steel, too.

The point of the thread isn't sharp in any material; tip and root radius (or bevel) is part of the spec.

Tri-lobes are for self-tapping, and don't affect galvanic reactions since there's still metal to metal contact between bolt and part.

I agree; they aren't using a 'normal' hand tap for any of it.