The main issue of how too many modern cars are put together in terms of working on them is this removal of several assemblies to access the broken part means that you're taking the chance of breaking them on the way in and the way out.
Some parts rarely break and you can nest them deeply.
But when it's a component that MUST be replaced every time a seal is broken, you don't make that part hard to get to if you're an engineer worth their salt.
Case in point is having to get the condenser out to replace the desiccant pack.
You have to break three seals to remove it and this introduces the risk of these seals leaking after reassembly. Now you have three places to look for the leak instead of one.
Then there's the massive proliferation of single use fasteners.
What a racket.
Make it so you have to remove, at least, two unrelated assemblies to access pieces that you KNOW are going to wear out then require the customer to purchase all new fasteners.
Never mind that a lot of those "single use" fasteners were specifically designed to be reused.
Prevailing torque nuts were designed to address two issues of the old Nyloc nuts. First was nylon melting in high temperatures. Second was a used Nyloc is no better than a normal nut for locking once it's been removed.
Prevailing torque was designed to be reused.
As the male fastener reaches the deformed section it stretches the threads of the nut elastically back into a circle. This action increases the friction between the nut and the fastener greatly and creates the locking action. Due to the elastic nature of the deformation the nuts can be reused indefinitely.
But GM says to toss them every time.
Almost as if they developed a procedure for lock nuts based on the Nyloc and never amended it for prevailing torque...
In one aspect, it makes some sense, the mechanic doesn't know how many times the nut has been removed, so it's safest to replace it.
But if you're going to treat every locking nut as if it were a Nyloc... Why not just use Nyloc?
Which brings me around to an elephant in the room.
The engineers the automakers are hiring.
A lot of modern cars are packaged more and more in an aviation style, with an aviation attitude towards fasteners.
Aviation is the coolest kind of engineering, after all.
Aviation style decisions made by the least experienced engineers without moderation from more experienced engineers.
Where did the experienced engineers go?
Well, they keep getting fired laid-off when the assembly line apes threaten to strike and the automaker has to cut payroll to accommodate the union's plan.
I sometimes wonder how many of those senior automotive engineers went into robotics just to strike a blow at the UAW.
Aerospace has union problems, too. My brother has worked there since 1987 (McDonnell Douglas and Boeing) and he has nothing good to say for the unions in that industry. I'm not so sure that there should be a "right to strike." Walk off your job? Fine! But you don't own it, so don't come bawling when someone else grabs it!
ReplyDeleteModern cars (and most everything else) are designed to be the cheapest and quickest to be assembled (as you found out with Precious). Ease of service and durability are not even considered. They also don't want them to last more than 10 years or 150,000 miles. They want you to buy something new. Add to that the quest for an extra 0.01 MPG and you have a real mess.
ReplyDeleteI no longer remember the specifics, but an early 1970s Fiat sedan required removal of the radiator and some other components in order to remove the oil filter.
ReplyDeleteA 1981 Ford Mercury capri required lifting the engine off the motor mounts in order to reach the oil filter. The job could be done from underneath, but that required removing the radiator.
The starter on a 1973 F-100 was held by three bolts. Access to one of those bolts required a articulating arm that bent in a minimum of three places. No, you cannot actually see the bolt, nor is there room for a mirror. Of course, lifting out the engine was an option.
My younger brother, the most gear head of us all, gave up performing engine maintenance on his 50th Anniversary Ford Thunderbird. It came to a point where he'd pop the hood and stare in disgust at where the engine should be, but was buried beneath rubber panels and electronic components out the wazoo.
ReplyDelete$145* for an oil change at the dealership. Changing filter extra.
* If no 'difficulties' arise. There were always difficulties.
I'm making an exception for anon comments for this post as long as they stay on topic.
ReplyDeleteIt's a competitive market, and anything that's not important to making a sale gets optimized away. Maintainability included.
ReplyDeleteI work in a field where the total cost of ownership, including maintenance, is considered. All the equipment is designed to be serviceable, and customers make actual purchase decisions based on whether a piece of equipment will be easy or hard to service. It costs more up front, because serviceability, ease of initial assembly and cost all compete with each other.
When we see people buying cars advertised as "easily user serviceable," those cars will be easy to maintain. They will also be more expensive. Of course, it'll happen around the same time as I get my wish for an open source ECU. (When pigs fly, that is)
Daosus