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Well.. let me ask you this:
- why put a starter in the back of the engine, between the engine and the firewall
- why put a starter in the oil pan
- why put an alternator at the very bottom of the belt driven accessories of a transverse mounted engine
answer these 3 riddles and ye’ shall be granted passage across the bridge of death.
Like BMW removing the transmission AND engine oil dipstick and I think it’s VW that requires a special tool to measure transmission fluid levels. Making it more difficult for DIYers to do stuff under the hood. BMW requiring you to replace the transmission fluid from down below with a fluid pump!
Apple using proprietary screw types for no reason.
Some might say it is a case of overengineering (making it more complex for no reason), others say it is to get more cars into the dealership repair shops. Other say it is natural and is necessary to make a more refined car. Ugh.
Cars are more complex these days with tighter tolerances, more parts, more electronics and that IS the natural progression of things. But certain design decisions make no sense from any point of view.
I’m in school for Computer Engineering/EE with an interest in automobiles, will be interestingI have worked on projects, and it doesnt have to be technical/mechanical, sometimes it is just someone higher up in the food chain that changes it for the worse. All people involved will fight tooth and nail or just grumble on how !!@**! stupid it was but have to live with it. I am thinking this runs across all industries, it may not be the person or people that design the product but some exec that is completely removed from the process and either wants to be involved, wants to flex their muscle, or for whatever reason thinks they are right that screws it up.
On the other hand when it comes to sealed units like transmissions these days or proprietary screws as someone mentioned, I can see why. If a company has to warranty something and you know you have a good product you may not want the end customer going in and screwing it up and then putting it back together and claiming its a product defect. It gets officially logged as a warranty claim, lowers the ranking in whatever survey somewhere, and costs the company time and money for the company because someone monkeying around thinking they thought they knew how to fix something ends up breaking it. Anyone that has been a technician in anything knows what I mean. Not saying anyone on here would do that but there is a reason we all watch ETCG. :whistle:
Sensotronic brakes on some 2000’s mercedes. Any brake pad change that starts with something like “if you don’t deactivate proper, you could lose your fingers!” does not appeal to me.
Warning: I’m an engineer, but not a mechanical one. However, the idea behind is generally the same across the field.
Firstly I’d like to say that I feel for you guys. Now don’t take it wrong; we engineers are engineering because we love what we work on. Things we work on are our brainchildren, end product of long hard struggles with hundreds of thousands of decisions. And at the end of the day, we like to see nothing more than people using our work and be happy for it, having improved a whole lot of peoples’ lives. That’s what engineering is all about, afterall.
Unfortunately, you’re right in that engineers are still rooted in reality and we have a LOT of people to answer to. We don’t forget about mechanics either; were I a car engineer, you guys would be one of my major stakeholders in the end product goal. However, the biggest stakeholders tend to be the business owners, mainly the employers and managers, and they generally tend to make the end business decisions and thus engineering decisions.
Trust me when I say engineers (generally) have noted down every single bolt and nut and screw and wire down to a science in every single one of your cars. When you do see something out of order when pulling your car apart, it’s very most likely there not because one engineer was sleeping on the job (we do work in teams, whole team was sleeping?), but because he or she actively decided on it. Examples to ponder (as thought by one engineer, not a car one though):
– how much will the whole parts cost for x design?
– during initial manufacturing
– during dealership warranty repair period
– during post-warranty repair period (this is often extremely low importance on business requirements, I’m sure you’d understand why)
– are other parts of the car affected?
– can be materials / parts be acquired easily?
– does it meet x y z standards?
– how long will it last until it has to be repaired?
– how long does it take to install this part?
– is it modular and sellable as an upgrade feature?
– can this be used internationally?
– can this all be done before next financial year when new models are released?
– etc etc…and be prepared to have a ~20 page document per part that goes in the car on explaining everything above, and more, and why it was engineered as such, to be signed off by rest of decision makers e.g. managers, auditors, “strategic decision makers”, etc. You don’t just go “uh, that’s a stupid idea, fix it”, and it’s just fixed then and there. If only if.
That said, if you ever find a pain in the ass part to replace in a car, what most likely happened is 1. car is designed to life of x number of years, and 2. part is engineered to most likely fail well past that lifespan. Of course, statistics kick in, and sometimes it does fail earlier, and that’s when you go to dealers for warranty repair. That’s all calculated already; someone decided it was cheaper to hire mechanics as aftercare for the car, rather than try to spend more time and money to re-work the base car design.
Sometimes though, it really is the engineer who failed massively and end up costing everyone frustration, time, and money. We’re human too, afterall. We just hope to learn from the mistakes and move onto newer and better things.
Hope the rant wasn’t too long. I’ll try to answer any engo questions if anyone has them, but I suspect there will be others around these parts to have a say too.
2 things I have always questioned:
1.On the Honda xr650r from about 2000-2007 models have a oil dipstick in the frame just in front of the gas tank however if you don’t have the stick in perfectly with the threads lined up it will cross thread and you end up with a dipstick that looks like a cork screw. I changed the oil in mine today and it took me almost an hour to get it threaded in right! But I love the bike
2. Fuel pumps in the gas tank with electricity I’m just curious who decided that would be a good idea to try? I know they have alot more pressure than the old mechanical ones but how would this cross your mind “lets put a cylinder thing in a pool of gas and add electrical current”
lorentz is right.
I’ve been in the warranty business.
Some parts indeed fail on the manufacturing side. It may be from a material defect or on how the manner it was made. It can even be some problem in the production line. (i.e. a bolt suddenly becoming loosened after some period of use). Don’t expect them to scrutinize every last bit of defective product that gets passed the production line. You can’t blame it all on them. Higher-ups make the decisions. The purpose of starting a business is making a profit. Balance between cost and durability. Otherwise, there won’t be anyone to make these stuff.
After all nothing lasts forever.
[quote=”Passey” post=58119]
2. Fuel pumps in the gas tank with electricity I’m just curious who decided that would be a good idea to try? I know they have alot more pressure than the old mechanical ones but how would this cross your mind “lets put a cylinder thing in a pool of gas and add electrical current”[/quote]There is no oxygen in the gas, the gas pump is always submerged (unless you run dry). So unless it runs dry, there is no way a spark from the pump can cause ignition
When they put 3 plug and wires under the hood in easy access and 3 up under the engine that “Rubberman” would have trouble getting to, that seems more a marketing and finance decision than an engineering one. No engineer worth his salt would design an engine that way. And when NASCAR can design a car in which a driver can walk away from a 200 mph crash, and 40,000 Americans a year die in car crashes, I don’t think that is an engineering issue but a financial one. And airplanes can fly for tens of millions of miles for 40 or 50 years but we have trouble getting 150,000 miles out of our cars. Of course those planes cost millions and have complex maintenance time tables that must be followed. In my opinion, it goes against everything the car companies do to make a car that will remain maintenance free beyond 7 or 8 years, more or less. They want most things to last at least through the end of the guarantee but then they don’t really care since the obviously want us to buy a new car. Aircraft manufacturers are not concerned with the owner buying a new plane every 5 or 7 years, but car manufacturers are. Just look at the trucking and heavy equipment industry, they build products that last for years and years and take a hard beating everyday. Sure they breakdown but they also make them fairly easy to work on, even easier than a consumer’s “cheap” $20,000 car.
You’ll find that older cars are sometimes more reliable than newer cars, like 1990s Honda Civics/Accords. If you keep the fluid clean and don’t go nuts with them they are very reliable (besides needing an updated new ignition switch part# and maybe an updated rear trailing arm bushings.
I’m not an engineer but in their defence, I have to say, it’s often not their fault that assemblies and fittings appear to be badly placed so as to be inaccessable to repair/replace.
Design and manufacture by ‘Accountants’ is the norm these days; accountants demand that a new product is disassembled and then reassembled, minus a particular part, then they see if it still works. If the item still works, they repeat the same process until it doesn’t work, then backstep and replace the last part that was removed to enable a ‘so called’ final working product that is cheaper to manufacture in bulk. Having been through the process of “design by accountancy”, the finished article often bears absolutely nothing in common with the original design specification, other than in works in principle!
Rather than blaming engineers for all our woes, perhaps we should direct our scorn at the faceless “Accountants” who dictate how modern manufacturing performs, as well as the “Bankers” who place a financial sranglehold upon the engineers, who’s only desire is to produce a ‘perfect product’.I’m a Mechanical Engineer at an automotive supplier, and a lot of what Eric said is true, but there was one major point that was left out.
The cars were built to be manufactured in a specific order of assembly in the least time possible. Because of this, you will always find things that are difficult to reach without removing something else first. Design for service is typically a low priority.
As Eric pointed out, the styling of the vehicle has an influence as well…If we had exposed screw heads, no engine covers, and non-clip together panels, we would be universally panned by the car reviewers.
The “bean counters” which in most cases are “Purchasing” people are the drivers of a lot of this. They always force us to make something more cheaply than originally intended. The OEMs also put price pressure on the suppliers in the same way. The companies are there to make money – so we have to balance price and quality. These purchasing people also know little to nothing about design.
The other thing you will see is that parts are carried over from chassis to chassis which sometimes causes unanticipated issues with repairs.
With that being said, German cars seem to be designed to not be repaired by a DIY person or independent shop.
The car companies are selling these to the new car buyer. They could care less about the guy who buys it used that they make nothing on. The average buyer of a new car doesn’t even change their own oil ( in fact some of the factory warranties out there are voided if you don’t bring it directly to them.) So they don’t worry about it being easy to work on. They need to build it on an assembly line as cheaply as possible. Realize they only make about 3-5% profit on these cars. So anything to keep costs low helps them compete with the rest of the car companies.
I loved this video… it really put me in perspective (“Yet Again”), I always would sit there and get upset at a design and the first person I want to strangle was the engineer! Now I have learned to just accept that the engineer is not the sole individual making life difficult on purpose and in many cases have seen where it’s the “Bean Counters” I am in fact after now! (DoD employees don’t like bean counters… I guess unless you are one I suppose.)
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