Designed for repair

[tlynch]

After recent fun and commiseration over the serpentine belt tensioner on a 1995 E300D, I began to wonder what life would be like if engineers included ease of repair among their design considerations.

So here is my question:
What parts get replaced so often that cars should be designed to provide easy access to them using only commonly owned hand tools?

And related followup:
What is your worst nightmare story of a job that should have been easy, but was thwarted by the slimmest of margins?

I lead with serpentine belt and associated tensioning parts on a 1995 E300D. 10 minute job turned into a multi-day endeavor by 2-3mm of extra bolt length.

A neighbor told of removing a starter from its position fairly quickly only to find that he had to disassemble the suspension on one side to get it out of the car. Year, make, and model unknown.

Next?

Regards,
Tom Lynch

[4x4_Welder]

Power steering v-belt on Jaguar V12, had to take off four other belts with threaded tensioner bolts in nearly impossible locations.
Swapping EFI 5.8l v8 in an E150, there is a bolt to remove the intake that must be accessed from the top yet the tool for it won't fit down into the hole because the dash is in the way. I had to use a T35 bit with a 1/4" wrench at about 1/12 of a turn at a time to get the bolt out. The intake had to come off to get the engine out of the van, so it was a real royal pain.
Oil filters on front wheel drive VW four cylinder engines are another pet peeve of mine.

[W124 E300D]

Originally Posted by tlynch

After recent fun and commiseration over the serpentine belt tensioner on a 1995 E300D, I began to wonder what life would be like if engineers included ease of repair among their design considerations.

So here is my question:
What parts get replaced so often that cars should be designed to provide easy access to them using only commonly owned hand tools?

And related followup:
What is your worst nightmare story of a job that should have been easy, but was thwarted by the slimmest of margins?

I lead with serpentine belt and associated tensioning parts on a 1995 E300D. 10 minute job turned into a multi-day endeavor by 2-3mm of extra bolt length.

A neighbor told of removing a starter from its position fairly quickly only to find that he had to disassemble the suspension on one side to get it out of the car. Year, make, and model unknown.

Next?

Regards,
Tom Lynch

there is nothing wrong with the serp belt design, you just did he job wrong.

[chazola]

I find myself cursing out the engineers who put older mercs together with annoying regularity. I blame German advanced technology coupled with the need for exacting tolerances in everything. Sometimes I think they deliberately made it difficult on the RHD cars 'cause they lost the war, and all the German vehicles have much easier engines to work on
I think most MB's weren't designed for home or street-corner mechanics, they were meant to go into big shiny dealer workshops with all the right specialist tools and manuals to hand.

Despite usually having an engine bay the size of a house to work with, everything will be crammed together on a merc engine, over-complicated and over-engineered, with the bolt/nut/screw you need to get at buried behind a pipe or other bit of engine accessory, meaning you have to dismantle half the car turning every 5-minute job into an hour + one... I had the thermostat cover off the 250SE the other day- 2 nuts easily accessible and off in seconds, the other 2 buried under the metal fuel delivery lines and so close to the valve cover you can barely get your fingers in and only get a non-ratchet wrench in there and turn a quarter-turn at a time... grrrrr

Saying that, the 124 is actually very easy to work on compared to the 108, with all the filters easy to get to from the top of the engine bay. I think a bit more thought to easy maintenance went into those cars.
Once you've done a job once on the 124, doing it again is (usually) a lot quicker...

[MBeige]

My friend just got a W140 M120-powered S600.

Changing the oil (extracting the oil filter) is a nightmare! Many parts have to be removed just to get the oil filter.

That M120 V12 is just crammed in the engine bay!

[dude99]

The bloody starter motor on a w123.... Took me 2 days to get it out the first time only to find they had sold me a bum part.... The next R&R I did took only 20minutes...

[pawoSD]

Originally Posted by chazola

I find myself cursing out the engineers who put older mercs together with annoying regularity. I blame German advanced technology coupled with the need for exacting tolerances in everything. Sometimes I think they deliberately made it difficult on the RHD cars 'cause they lost the war, and all the German vehicles have much easier engines to work on
I think most MB's weren't designed for home or street-corner mechanics, they were meant to go into big shiny dealer workshops with all the right specialist tools and manuals to hand.

Despite usually having an engine bay the size of a house to work with, everything will be crammed together on a merc engine, over-complicated and over-engineered, with the bolt/nut/screw you need to get at buried behind a pipe or other bit of engine accessory, meaning you have to dismantle half the car turning every 5-minute job into an hour + one... I had the thermostat cover off the 250SE the other day- 2 nuts easily accessible and off in seconds, the other 2 buried under the metal fuel delivery lines and so close to the valve cover you can barely get your fingers in and only get a non-ratchet wrench in there and turn a quarter-turn at a time... grrrrr

Saying that, the 124 is actually very easy to work on compared to the 108, with all the filters easy to get to from the top of the engine bay. I think a bit more thought to easy maintenance went into those cars.
Once you've done a job once on the 124, doing it again is (usually) a lot quicker...

RHD cars are harder to work on because you all drive on the wrong side of the road, and thus make it difficult for engineers who then have to make *special* cars for you all to drive.

I find no issues working on my MB's....some things are tight, but after working on some Buicks and Toyota's.....I'll stick with MB. At least stuff comes apart without breaking!

Obviously the newer your car is the more complex it will get, thats how it is with most cars.....and is why I am sticking with a pre-1995 fleet.

[635CSi]

Mazda Millenia S, Miller Cycle engine, enough said

[tlynch]

Originally Posted by W124 E300D

there is nothing wrong with the serp belt design, you just did he job wrong.

Or you and I have different motors, and our results vary.

Regards,
Tom

[75Sv1]

I'd say oil filters, air filters, fuel filters, O2 sensors and spark plugs. I know the last one is like 'what's that'. Some cars aren't diesels, they just dream to be. I'd also add the AC clutch to FWD cars.
Some late 80's Hondas has the air or oil filter buried deep on the back of the engine. A lot of transverse mounted V-6 cars, the spark plugs are difficult to get to.
My 240D is fairly easy to work on. Also, Jeep Comanche and Cherokees have some room to work on them too. Straight 6s and straight 4s seem to have a lot of room around them.
Tom

[vstech]

OMG, the list is outrageous...
try changing the water pump in an old plymouth... after you remove all the bolts from it, you need to know that under the thermostat inside the housing there is another bolt holding the water pump from the inside...
or the starter motor on a 90's corvette zr1... first off it sits in the valley between the heads... UNDER THE TWO INTAKE MANIFOLDS!! second, any excess rainfall on the car, and water will collect in the block valley, and submerge the starter... rusts it solid...

[babymog]

How about a Honda Rav-4 starter, have to remove half the suspension to get it out.

[tlynch]

Originally Posted by vstech

or the starter motor on a 90's corvette zr1... first off it sits in the valley between the heads... UNDER THE TWO INTAKE MANIFOLDS!! second, any excess rainfall on the car, and water will collect in the block valley, and submerge the starter... rusts it solid...

Yikes!

I have had the feeling with my Mercedes that the design expectation was that the car would always be garaged. In reality, since the car lives on the drive way, leaves and moisture end up making mulch behind the fenders.

I'm sure that Corvettes come with a similar design expectation of garage living, and also an expectation that owners would applaud performance-oriented design (like center-mounted starters), and be able to afford the shop time needed for any tear-down required.

Regards,
Tom

[strelnik]

Originally Posted by tlynch

Yikes!

I have had the feeling with my Mercedes that the design expectation was that the car would always be garaged. In reality, since the car lives on the drive way, leaves and moisture end up making mulch behind the fenders.

I'm sure that Corvettes come with a similar design expectation of garage living, and also an expectation that owners would applaud performance-oriented design (like center-mounted starters), and be able to afford the shop time needed for any tear-down required.

Regards,
Tom

After working on the 616 engine and the 636, even taking out glow plugs from a 606 can be a challenge.

However, it was impossible to get the plugs out of the old Chrysler 1970-71 440 V8 on the B-Body. In the second year of production, they punched a hole and made a removable panel at the stamping plant, because the dealer mechanics and the race nechanics couldn't access them!

[LUVMBDiesels]

Anything on the 1984 BMW was a nightmare to fix. They crammed everything in as tightly as possible. Same thing on the 1995 Volvo and the 2004 Volvo. Lots of body braces and things like sway bars that have to come out to get to anything.

The worst job were the rear facing spark plugs on a V6 Taurus. You could not even see them, much less get a wrench in there to remove them. Close in trouble was the #8 plug in my old Impala. It was next to the HVAC tucked in so tightly that you could barely get a wrench in there to fix it.

Oh, and the timing belt on a Ford Escort! What a nightmare that was!

In contrast the 603 in the SDL was a pleasure to work on. Topped only by the joy of working on the CJ-5 six cylinder!