An engineering lesson

[enginesrus]

This fellow is great at auto diagnostics. What is good about this particular video are the comments about engineering.
The one I enjoyed the most was the comment that the engineer that designed a power steering pump and had no idea where it would fit on the car.

https://www.youtube.com/watch?v=gItRHOmhtp8

 

[gruntguru]

Had to fast forward through most of the video and missed the power steer comment. He's a good tradesman but he's not an engineer.

It is easy for tradies to pass judgement on engineers/architects etc because they have no idea of the constraints within which the original design was undertaken.

je suis charlie

 

[GregLocock]

If a P/S pump doesn't need to be fixed within the warranty period then its replacement cost will get a very low weighting in the total cost of ownership rating. Which is a thing. Packaging used to be done by building a car out of plywood and moving the foam blocks around until they fit. These days you start with volumes, actually locating the parts where you'd like them to be is a luxury. A lot of that is driven by the downpipes and catalysts which cook anything close to them, leaving large parts of the car unavailable for packaging. Also of course we are squeezing more and more parts in.



Cheers

Greg Locock


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[GregLocock]

It's not the p/s pump, it is actually the relay for the fuel pump. 5:57 or thereabouts. This truck is 17 years old by the way.

Cheers

Greg Locock


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[Ng2020]

Enginesrus
Ever worked in a product design team? Better yet, ever defined engineering requirements for a complex integrated system?
If so, why not tell us something positive, about how you guided the design process within all the various constraints to produce a quality product.

 

[CWB1]

Coming from someone that spent many years in automotive fabrication, there's a big difference between can and should. Obviously this can be repaired as shown, whether or not it should be done is a question for the engineers who designed that system. If this repair causes harm in the future then the question of whether the tech should be punished is a matter for the courts, but he can indeed be punished as evidenced by many past court cases. Just as engineers are held to professional standards in most everything we do so are techs.

 

[LadaTrouble]

Yes, as a mere mechanic I can easily pass judgement on those who know so much more than me...and do so everyday, shaking my head. Having to remove a front bumper just to change a headlamp bulb...when a simple window in the guard liner would be much easier, surely it's not going to blow the budget on the whole vehicle ? Or just a lack of communication within the design team ? It's the customer who has to pay this massive increase in labour time for a simple job...and he may not buy another vehicle of that brand again. I could go on and on about such design stupidity....but then the designer may ask if the vehicle is old enough to blow a bulb, what is it doing still on the road ?

 

[geesaman.d]

It is easy for tradies to pass judgement on engineers/architects etc because they have no idea of the constraints within which the original design was undertaken.

I agree that tradesmen often go overboard on commentary without understanding the full context, or realizing the benefits that were gained by packaging / building a component in a way that makes repair more difficult. Sometimes the thing they advocate simply doesn't make any sense when the tradeoff is considered. Mistakes happen sometimes and the full story never gets out.

That said, there are plenty of engineers who blindly follow the specs and don't speak up when the specs lack common sense. They maximize their performance metrics instead of building the best overall product.

Then there are systematic problems where the entire chain of command is being driven to do the wrong thing and nobody can stop it. That belongs to the leaders. (shuttle booster o-rings). I was briefly involved in the Beagle2 Entry/Descent/Landing System design, which failed, and it failed because the leader of the Beagle2 project was stubbornly convinced that NASA had been way too conservative in designing support systems, and forced the EDLS to be too thin / too light / estimate risks too optimistically. That was the design philosophy and it went splat. Nobody was hurt but the UK taxpayers paid a good chunk of that bill.

There is plenty of blame to go around; we all need to spend more time trying to improve the part that's within our control and listening to the other groups.

If I could make a request, have professional mechanics comment on the cost/difficulty to repair various models of vehicles. Not to bash engineers, but to give a complete picture of the vehicle. That way shoppers could show up well-informed about the repair issues.

 

[Tmoose]

Some decades past At least one of the monthly US magazines ( like Popular Science or Mechanics, etc) used to include the price of some common repairs in their road tests.
As a young(er) hoodlum 0-60 mph times were more important to me.

 

[GregLocock]

"Having to remove a front bumper just to change a headlamp bulb...when a simple window in the guard liner "

So you increase the build price of the new car by $3, and introduce a new set of failure modes, so that the owner of a 10-20 year old car is happier? Unless the problem affects a NEW car buyer, then frankly it is not going to get much attention. We sell cars to new car buyers, not to shade tree mechanics.

Cheers

Greg Locock


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[GregLocock]

In fact in 40 years of car ownership, including a 26 year old TR4, a 15 year old Corona, a 7 year old Mini, and a 10 year old Escort, and (currently) a 17 year old Astra, I have replaced exactly ONE globe/headlamp/bulb whatever, the sealed beam unit on the Escort. The only failure I've had on the Astra in 12 years is the ridiculously expensive ignition coil pack. Oh, and one battery. And 4 tires. At the last service they were mumbling about brake pads.

Cheers

Greg Locock


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[LadaTrouble]

''We sell cars to new car buyers, not to shade tree mechanics.''

And the new car customer goes to the dealer for their servicing. If the vehicles has noticeably higher servicing costs for simple mundane repairs....they might decide on a different brand next time a new car is needed. But the important thing is to get the car sold, that's the money making part.

 

[GregLocock]

You aren't paying atention. Globes are not routine service items. If they were then they'd show up in TCO, and would be addressed. Fleet buyers care about TCO.

Cheers

Greg Locock


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[LionelHutz]

So the lesson is don't build vehicles that break when they are 17 years old???

Honestly, I'm not even opening a random YT video just to see how all engineers are doing it wrong according to someone who likely isn't an engineer or ever worked on a new vehicle design team.

As far as the the bulb replacement comment goes, probably half or more of the new vehicles sold would have that warrantied if it did fail on the first owner.

 

[enginesrus]

It is the COMMENTS at the bottom of the video, not the video.

NG2020, I signed a non-disclosure agreement at the last place I worked, ret now. Sorry no stories today.

 

[Lou Scannon]

Cop-out. You can relate anecdotes without disclosing IP.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[gruntguru]

NG2020, I signed a non-disclosure agreement at the last place I worked, ret now. Sorry no stories today.

je suis charlie