[Moto7451]

Very core parts of modern cars are essentially single use. Older engines could have the cylinders resurfaced or bored and sleeved. Newer engines have coatings and construction methods that disallow this. One scratched cylinder is now the end of a whole engine given the various matched parts that can’t be swapped block to block.

In the standard case this doesn’t matter as things last a long time inside an engine. The same is probably true for EVs.

When things go wrong all the repairability issues mean you’re out a car unless you’re willing to invest in repair. Is a 30K car worth a 20K repair bill? The Audi service department is happy to walk you to the sales department if not.

[_yb2s]

You can rebuild modern engines by boring out the block and installing a sleeve of the same block material and coating material, it’s just a lot more expensive. For a valuable car like a Porsche 911 this is typically done- the sleeves alone will cost 5-10k: https://lnengineering.com/porsche-996-997-987-3-4-or-3-6-96m...

[rasz]

Might be cheaper to send whole engine to Poland :)

http://www.krasnobrodzka-racing.com/alusil/ https://www.youtube.com/watch?v=_985nH-gUiU

Alusil sleeve job ~$4K for 6 cylinder, BUT you can go ~$1500 cast iron sleeves.

Mahle manufactures those sleeves in Poland https://www.youtube.com/watch?v=3GgPPIZHl-c always surprising to see how they "season" new parts by letting them rust in open air to relieve casting stresses. There is a good story about BMW racing engines being build from selected used blocks just sitting rusting away behind factory building for years.

[_yb2s]

Thank you! My daily driver is an early Boxster and this is great info on the Alusil. However, general advice I’ve seen on forums is that the iron sleeves don’t last in Porsche engines. The idea of sleeving with dissimilar metals sounds like a bad engineering idea as there will be constant relative motion with heating and cooling, and a galvinic cell near coolant passages.

[rasz]

This particular job from video was 996. In another video shop owner mentioned Alusil goes on most of them over >$100K range and iron sleeves will last at least that long. With iron sleeves you need different pistons/rings to match expansion rate.

[_yb2s]

It's a very controversial topic in the Porsche community, but overall it seems like the people that really know what they are doing and build reliable good running engines avoid the iron sleeves (e.g. https://flat6innovations.com/cylinder-bore-scoring/). Like you said- it requires using loose clearances which makes for a noisy, oil burning, short lived, and low performance engine... not what you want in a Porsche.

The factory coatings do fail in some cases- usually in specific engine configurations with issues, but very often last 300k+ miles... on the smaller bore M96 engines cylinder/coating failures are almost unheard of, even with very high mileage and lots of hard track use. Personally, I'll just stick with the smaller bore engines, and in the unlikely event it fails get a good used block where the factory coating is still intact. There's tons of the 2.7 and 3.2 M96 Boxster engines out there still running great with 300k+ miles, and you can buy a good used one for a few grand.

[rasz]

>Like you said- it requires using loose clearances which makes for a noisy, oil burning, short lived, and low performance engine... not what you want in a Porsche.

Thats opposite of what I said :) Only the startup noise applies, but lets not pretend M96 sound great :)

When something becomes veblen good logic goes out the window. >$100K 30 year old car restorations arent meant to make them peak performers, it becomes matched numbers everything as factory wankfest for cars sitting in a collection or driven only occasionally on the weekends. There is very little incentive doing cheap repair when everyone believes in expensive ones.

>There's tons of the 2.7 and 3.2 M96 Boxster engines out there still running great with 300k+ miles, and you can buy a good used one for a few grand.

Wanna bet they all have scored cylinders? :) Same goes for BMW Nikasil, no such thing as cheap used block with intact coating.

[eastbound]

An electric motor is dirt cheap compared to the ingenuity of an ICE. The battery is expensive because it’s a lot of mass of peculiar rare earths, but motors aren’t.

[ninalanyon]

> The battery is expensive because it’s a lot of mass of peculiar rare earths, but motors aren’t.

It's the other way about. Batteries in Chinese cars are mostly lithium iron phosphate. Not a lot of rare earths there. The motors are mostly permanent magnet motors and they definitely do have rare earths.

But anyway the name rare earths is mostly a misnomer, they aren't especially rare, less so than gold, copper, etc. They are just not conveniently located for extraction.

The batteries are expensive simply because the replacement battery market is not yet a large low risk mature market. This is in part because the batteries are lasting longer than most people, the manufacturers included, expected.

[woleium]

rare (in the) earth, i.e. well distributed, not lacking in quantity.

[ianburrell]

Lithium ion batteries don’t usually have rare earth minerals. Some use rare minerals like cobalt but they are moving away from those chemistries.

It is the electric motors that use rare earths but sounds like companies are moving away from that.

[Panzer04]

Not all that relevant from a maintenance perspective though. Electric motors essentially Don't Fail.

[rurban]

High-performance electric motors do fail all the time. They overheat, position sensors are slipping, the converters IGBT's last max 6 years.

You are talking simple engines, I'm talking high-end engines.

[Panzer04]

In the context of the motor alone, those don't fail.

The circuits driving it probably have a higher failure rate, but we've gotten so good at manufacturing electrical circuits it still seems much easier and cheaper than a mechanical engine.

[rurban]

I worked with high performance electrical engines. They do fail all the time. Not in cheap consumer cars though.

[wakawaka28]

In theory yes, but electric motors can be very complex in much the same way that ICE engines can be. Batteries of the kind used in modern EVs are single-use and far too expensive and dangerous to service. The level of effort required to maintain an EV past 20 years will be way higher than that required to maintain an ICE car that long. Very few ICE parts have a limited shelf life, and the ones that do are either consumable or else easily substituted such as rubber seals and belts.

This analysis is really just relevant for cars that someone would want to keep well-maintained for 20+ years at significant expense. Most EVs are boring so I don't expect them to be in that category either. But if you did really get attached to one, you might have to rebuild it from scratch with totally different internals to keep it going, and it would only look like the original on the outside.

[more_corn]

^ This comment consists of entirely made up bullshit.

[Ancapistani]

No, not entirely, at least not in my experience.

I’ve replaced three engines in the past ~15 years. The first was caused by a head bolt over-torqued from the factory, which led to a non-visible gasket failure and ultimately coolant making its way into the cylinders and destroying the block. The second was a failed pistol skirt. The third seized due to a manufacturing defect in a cam bearing.

All of those problems would have been cheaper and easier to fix in a 1980s-era vehicle. The oldest of these was a 2000, though, and it was cheaper to replace the entire engine than it would have been to buy the parts to repair them.

That doesn’t even include labor - and the labor required for many things these days is much higher than it once was.

[Moto7451]

Yup, this exactly. I don’t think engine failures are particularly common but I have had a few friends quoted roughly what their cars are worth to rebuild the engine from a new block or about 1/3 to replace the engine with a manufactured unit. Mostly Japanese and Korean cars.

[Moto7451]

I guess the $10k service bill for just changing a water pump in an Audi won’t impress you. Mercifully for me this 40K Mile time bomb went off under warranty. In a sibling comment they’re talking about getting a deal on cylinder sleeves for $6,000. In 2005 I had a top end rebuild done for $1200. I am 100% not spouting BS, times have just changed.

Shop fees and hours are very expensive for repair. When basic repairs involve disassembling the entire front of the car they add up. This is why YouTube mechanics often just drop an engine subframe and get an alignment after.

Third party mechanics don’t get access to all the tools and software anymore. VAG decided to increase the pain by requiring a license fee to access alignment information from next year onward for Audi, Porsche, and other brands.

Normally for anything I won’t wrench myself I’m happy enough with Pepboys service but increasingly they have to turn me away because they lack the tooling, software, or expertise for a job, and we’re no where near talking about machining an engine.

Rebuilding that damaged engine needs a specialty shop. They’re not just spinning a bore hone on a drill anymore. Coupled with overall improved designs and there just isn’t the same market for the work that there used to be.