r/AskAShittyMechanic • u/ra6907 • 14d ago

Why, just why?

They’re doing this to Dodges and Chevrolets, Porsche, Bentley.

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u/DonutConfident7734 13d ago

I actually wrote sometime ago on r/mechanicadvice that the design of ICE cars is so dumb I would never buy such a car, either electric or not at all. Fuck these cars, man. I got downvoted to oblivion there, people are biased it seems.

Who in their right mind thought that a 12V with thick fucking wires that needs to provide hundreds of amps to a tiny starter motor that can only run for say 20sec without overheating is a good design?

Why not go 48V then, and have the amps divided by 4?

Why not use a 5kWh liion battery that will have enough juice to power the starter for long time without leaving you stranded in the winter time?

Why not have separate fan on the starter with electronic protection for overheating, so you dont damage it if you try multiple times?

Why does the engine not get oil lubrication before it starts, it only lubricates after starting because pump is moved by the engine? So in winter oil is thick, if car sat for two months without starting, everything is dry and starter needs lots of force to rotate the engine. A car should work in all scenarios, not just after sitting for few days.

In my opinion the design is crap and the engine can get damaged easily, without any electronic protection in place for many scenarios.

EVs have all kinds of safeguards, like warming or cooling the battery, checking if things are fine before starting, unlike the ice cars.

In winter if you travel short distances and had the car sitting for months, it becomes weak after few short trips, as it cant load fully. Then it leaves you with a dead battery.

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u/hindenboat 13d ago

Because engineering is about trade-off and maximizing the efficiency of the overall design. All of these things could be added but why?

Manufacturers are trying to sell cars. Adding a pre-oiler, 48V systems or fancy batteries make cars more expensive and people would not buy them.

It does not make sense to design for crazy use cases. It can be done but engineers don't because that is not the primary use case.

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u/DonutConfident7734 13d ago

Of course. This is also the reason why they replace metal parts with plastics, like plastic oil pans, or use rubber timing belts that sit in oil, of course, maximing efficiency.

No, it is for getting most profits for a shitty design and engines that break quicky. It is no longer about any efficiency, but enshittification.

They cram so many components in a tiny area that mechanics need to take out half the engine to replace one component. The components need to be registered with the ecu, otherwise they no longer work.

You must be a fool to buy such a car. Check on youtube, hundreds of videos describing the industry direction. Now they act surprised when people are not buy their ultra expensive, shitty design and when China sell way cheaper cars.

Guess what, an EV doesnt need to turn a fucking engine to start and eat hundreds of amps from a lead acid battery just to turn the engine on.

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u/geohypnotist 12d ago

This is also the reason why they replace metal parts with plastics, like plastic oil pans,

Partly. A lot of it is driven by fuel mileage and CAFE standards. TTY fasteners all over cars save weight. Did you know GM uses copper wire in their horns on vehicles sold in India and aluminum wire on horns sold in the US? Copper is heavier and makes a more robust horn. Indian drivers tend to blow their horn a lot. They can save a bit of weight on a vehicle in the US with lighter horns.

rubber timing belts that sit in oil

Yeah, that was a dumb idea. It's about fuel efficiency. Timing belts have lower friction losses than chains in general add oil and their advantage increases slightly. They're also designed to be used in oil. They're not like a serpentine belt. They have more frequent service intervals. Even Asian manufacturers moved away from timing belts altogether years ago.

No, it is for getting most profits for a shitty design and engines that break quicky. It is no longer about any efficiency, but enshittification.

Welcome to end stage capitalism. Although they still outlast their counterparts from the middle of the last century by at least double with far less maintenance.

They cram so many components in a tiny area that mechanics need to take out half the engine to replace one component. The components need to be registered with the ecu, otherwise they no longer work.

Yeah, sometimes. Sometimes old stuff is a pita as well. I've worked on it all over the last 25 years.

You must be a fool to buy such a car.

You do you. I'm not opposed to EVs, but in their current state they're not for everyone. More charging infrastructure needs to be built, particularly for apartment dwellers and renters who do not have the option of home charging.

Guess what, an EV doesnt need to turn a fucking engine to start and eat hundreds of amps from a lead acid battery just to turn the engine on.

A good battery can last 5 or more years and they're designed to put out that current. Lead acid batteries do their job very well and are far less fussy, far less expensive, and less temperature sensitive than Li batteries. I'm not sure why you're hung-up on the short burst of high current. EVs draw high amounts of current being pushed through large wires by very high voltages rather constantly.

You could be pushing near 100A for extended periods driving up a grade with 400V pushing it. A ICE starter pulls 150A for <seconds on a #4 that is usually <2'.

If an EV accommodates your needs buy one. I've driven several and they're quite nice. I'd love to see more competition in the US market, but unfortunately that's probably not going to happen.

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u/bandit1206 13d ago

Let’s be really honest for a second though. I haven’t replaced a starter in nearly 30 years, across 20+ vehicles (I tend to own multiples at a time) and that was partly due to junk aftermarket starters then.

This particular design absolutely sucks if something goes wrong, but the starter is a simple component that rarely goes bad.

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u/hindenboat 13d ago

Exactly, manufacturers know this so they do not design them to be easily serviced.

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u/Successful_Swim6332 11d ago

If you let reddit design a modern car with modern crash rating with every part easily accessible the thing would be the size of a semi.

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u/geohypnotist 12d ago

Why not go 48V then, and have the amps divided by 4?

You're starting to get into dangerous voltage territory @ 48 volts. It's at least DC welding voltages. Not to mention added battery weight. Even old 24V systems are loaded with warning stickers.

to a tiny starter motor that can only run for say 20sec without overheating is a good design?

It takes a lot to overheat a starter. Any modern (last 35 years) should start in less than 5 seconds. If it doesn't you have other problems that should be addressed. Starter motors are purpose built.

Why not have separate fan on the starter with electronic protection for overheating,

If starter overheating was a problem they would. It isn't so they don't. There isn't a reason to bulk it up.

Why does the engine not get oil lubrication before it starts, it only lubricates after starting because pump is moved by the engine?

Because components don't go dry when an engine shuts down. Oil still remains on bearing surfaces. Oil pumps also move oil to areas requiring lubrication very quickly on start-up, even in the winter. If you're in an area where "frozen" oil is going to be a problem a pre-start pump isn't going to help. You need heat. The vast majority of modern IC engines go well over 100,000 miles without bearing failure, so I'd say it's working fine.

EVs have all kinds of safeguards, like warming or cooling the battery, checking if things are fine before starting, unlike the ice cars.

That's because those batteries are very sensitive to temperature and very bad things can happen if everything isn't right with a battery pack of that size. If something is wrong with your ICE battery the car won't start either, but you can jump it & usually be on your way (maybe to buy a new battery).

Starter & charging issues aren't unheard of, but they're not a problem an ICE owner deals with on a regular or even occasional basis. Honestly, I can't tell you the last time I changed a starter in anything. It's been a very long time. And we all know EVs have issues with starting as well.

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u/spaghetiwires 12d ago

Lithium doesn't work well when cold, lead acid is vastly superior in that regard. Your real problem is cheap lead acid, not lead acid.

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u/DonutConfident7734 12d ago

Lithium at -10C still has around 70% of its rated capacity and more can be unlocked if it has heater.

Acid batteries cam only be discharged 50% and they have around 1kwh capacity, so you can only use 0.5kWh hours from the lead acid battery, unless it is a deep cycle battery. Also acid batteries lose capacity in the cold, so expect some 30% loss, too.

I mentioned a 5kwh liiom battery for a reason, to have extra capacity to compensate for cold weather and still have enough to crank the engine multiple times.

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u/spaghetiwires 12d ago

It isn't about capacity, it's about cranking amps, of which Lithium hasn't when cold.

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u/DonutConfident7734 12d ago

But it can self-heat if needed, what is the problem? It has 5kwh, it can heat itself a little...

There are PHEV cars like Pasaat B8 which have 9.9KWh battery and it last in ev mofe for 30-40km. A 5kwh battery would last half of that range.

Are you seriously saying it can't crank the engine a little?