What are some car-repair jobs you always wished you could do

On Tue, 7 Nov 2017 00:35:45 +1100, Xeno <xenolith@optusnet.com.au>
wrote:

On 6/11/2017 7:02 PM, clare@snyder.on.ca wrote:
On Mon, 6 Nov 2017 04:48:30 +0000 (UTC), RS Wood <rswood@is.invalid
wrote:

Xeno wrote:

Any scoring on a rotor will fail it. As you say, there might be less
than 50% of the pad surface in contact with the rotor surface. No way
will that bed in properly. You will get localised overheating both on
the pad and on the rotor.

I'm not gonna argue vehemently because, in practice, while I've seen those
"wavy" rotors too, my rotors tend to be smooth so I don't deal with
"scoring".

However, anyone who says "any scoring of rotors will fail it" has NOT looke
up the manufacturer's spec for scoring tests.

I have. Long ago.

The result was shockingly huge.

I don't remember the actual number but I remember being shocked at how huge
it is. Something like tens of thousanths of an inch in width huge.

We're talking Grand Canyon in rotors.

I may be wrong but if someone says "any" scoring, that's just preposterous.
Let's see a manufacturer's spec for anyone who says that.

Sorry. It's just not logical that 'any' scoring fails a rotor.
ANY mechanical damage fails the rotor on DOT test. Some smoth wear is
allowed - but you NEVER install new pads on rotors that have an uneven
friction surface because it is virtually impossible to properly bed
the new pads to the uneven rotor withot localized overheating

Exactly. The new pads will charcoal grill on the high spots and *never*
properly bed in.

At the price of rotors today even on your Bimmer, it just is not
worth it. The pads cost more than the rotors on MOST vehicles today.
No reputable shop will do it because comebacks are expensive - and
real mechanics KNOW the comebacks will happen if they do something
stupid like installing new pads on badly worn rotors.

Brake pulling is most likely as the most grooved disc will have less
surface contact.

Untill it does finally totally wear in - when it will have more - so
either way you can't win with grooved/worn rotors.

 

On Tue, 7 Nov 2017 00:44:59 +1100, Xeno <xenolith@optusnet.com.au>
wrote:

On 6/11/2017 8:44 PM, clare@snyder.on.ca wrote:
On Mon, 6 Nov 2017 17:23:01 +1100, Xeno <xenolith@optusnet.com.au
wrote:

On 6/11/2017 3:49 PM, RS Wood wrote:
Xeno wrote:

I have Toyotas precisely because they have a chain.
Some do, some don't. (perhaps today they all do - not sure)

The ones I buy sure do! ;-)

Two vehicles that are worthless to me:
1. FWD
2. Belt

The past half dozen cars I've had have been FWD. I don't have a problem
with them. My first FWD car was a Morris Mini back in 74 and I have had
heaps of them since. Had heaps of RWD cars too. Totals in the hundreds.
2 mechanics/trade school instrctors who drove Morris Minis ----

First car was a Hillman Minx. Had a few before I bought the mini. 850cc
of raw power, 70 mph with a tail wind and a downhill run.

Thats a GOOD tailwind and a GOOD downhill. My 850 was the only car
I've owned that would go faster in third than in forth - and I owned a
'49 split-window bug. The mini was faster, but the bug could hold it's
own in top gear.

 

[RS Wood]

Ed Pawlowski wrote:

Doubt you'll believe it anyway.

https://ebcbrakes.com/articles/what-is-brake-fade/

It's marketing bullshit and it's track related, but it has nuggets inside
it just like all bullshit does.

For example, it's interesting they don't mention the rotor (but of course,
they're selling pads) when they say "Brake fade is caused by overheating of
the brake pad".

It's also interesting they talk about 'green fade' which makes sense since
a more complex look at friction reveals that there is a microlayer of pad
deposition on the rotor which "covalently bonds" in a way that I don't
completely understand, with the hot pad, where *breaking* those chemical
bonds adds to friction but only after a good bedding occurs.

They skip all that, and concentrate on water, surface area, and volatiles,
but I think the early fade is due more to the lack of covalent bonding than
anything else.

I gotta run so I'll get back to this, but it's a typical marketing job
trying to make believe they're being scientific when they don't mention
even once the pad ratings nor the word "warp", but I have to go before I
finished it as I have to pick someone up at the airport.

 

[RS Wood]

Xeno wrote:

I don't disagree that an automatic is a completely different thing to
rebuild than a manual would be for a typical rebuild.

Far more than most people realise. Even more complex now that trans
operation is integrated with a TCU and the ECU.

When I listed transmission in the original post, I meant manual, and
specifically I meant clutch which, as you know better than I do, means a
few more parts like
a. clutch
b. pressure plate
c. pilot and throwout
d. slave and master
e. flywheel

I'm not sure what else offhand, but had I just done the job once, I'd know.

I think the only "special" tools needed are a transmission jack and the
tools to align the clutch and pull out the old bearings where people jury
rig all sorts of solutions but where I'd likely buy the right tool.

Seems to me the special tools are about $200 to $300 at most, which is
about what the labor costs would be. And the job isn't like an alignment
where you have to do a lot more than normal thinking.

Maybe some day I'll do it but probably never.
I lost my chance, and I regret that.

 

[RS Wood]

Vic Smith wrote:

Only the stop-tech article is written by a pro (Can't open the
raybestos link so it's useless)

That "pro" says to replace brake fluid once a year.
I wonder how many people do that.
I never replace brake fluid unless I've got the system open.

I agree with you that the so-called "pros" say a lot of things that are
pure horseshit, but usually they're just super overly conservative (like
have your tires balanced every 10K miles or something like that).

You can't call them "wrong" but you can say "nobody does that".

I would agree with you on two things related to those articles:
a. I don't agree with everything they say (they don't even agree with each
other).
b. But the net is that what most people call warp isn't warp at all.

There are few technical car topics on the net more filled with bullshit
than rotor warp for street cars.

Nobody who says they have seen warp ever proves a single word they say.
That's a fact.

Just try to find a picture or video of someone testing their rotors for
warp (not runout!) and you'll see my point.

I'm done with warp because I provided references and I said it "can" happen
but it's not happening in 99.9999999% of the cases.

Anyone who wants to dispute the references need only provide a reference.

 

[RS Wood]

clare@snyder.on.ca wrote:

ANY mechanical damage fails the rotor on DOT test. Some smoth wear is
allowed - but you NEVER install new pads on rotors that have an uneven
friction surface because it is virtually impossible to properly bed
the new pads to the uneven rotor withot localized overheating

At the price of rotors today even on your Bimmer, it just is not
worth it. The pads cost more than the rotors on MOST vehicles today.
No reputable shop will do it because comebacks are expensive - and
real mechanics KNOW the comebacks will happen if they do something
stupid like installing new pads on badly worn rotors.

Rotors are cheap. $50 for Brembo or Myle.
I measure runout. I measure thickness. I measure thickness variation.
I look at scoring. I look up the specs when I need them.

In practice, it's pretty simple:
1. Replace the OEM Jurid/Textar pads with $35 Axxis/PBR FF equivalents.
2. Measure the thickness of the existing rotor
3. If it's too thin, replace with Meyle/Brembo for $50/wheel

I don't blame any shop for replacing *everything* they can.
The more they replace, the more they make and the less people come back.

That's just logic.

 

[RS Wood]

Xeno wrote:

The pads on my car(s) have both long life and good braking ability. Did
I mention they don't squeal too. They are the OEM Toyota pads that came
with the car and that's what they will be replaced with.

The only time you don't have to mention the friction rating is when you
purchase OEM pads. Otherwise, the friction rating is critical to mention.

I have nothing against OEM anything, but in the case of the bimmer, the FF
Jurid pads in the front make a black dust that is objectionable.

For some reason, which I don't believe the marketing of, the PBR/Axxis FF
pads don't have that objectionable dust.

Nobody has ever given a good answer since "dustless" doesn't cut it.

All pads and rotors must dust. So we just assume that the dust from
Axxis/PBR pads is not as objectionable as the dust from the OEM Jurid pads.

Both stop as well as indicated by the FF rating for both.

 

[RS Wood]

clare@snyder.on.ca wrote:

Not hard to understand at all. Uneven friction causes uneven heating,
and localized overheating causes enhanced friction material transfer -
which just cascades.

That must be it because you don't feel the effect of the primary pad
imprint. You only feel the effect over time when it builds up to enough of
the teeniest tinyiest amount to make the shuddering occur at speed.

My main point is that if people think their brakes actually 'warped' (ad in
a potato chip), the short term solution always works but their long term
solution can't possibly work.

The long term solution is, most of the time, to change their braking
habits. Until they realize that their brake rotors didn't warp, they won't
realize that the long term solution is what it is.

To me, that's the crime of people thinking their brakes actually warped.

Short term? Gently re-bed the pads. Works high percentage of the
time if you don't allow it to get progressively worse to the point you
get cabide inclusions in the rotors.

I know. I know.
But I was summarizing.

You can scrape the deposit off a bunch of free and easy ways.
1. Easiest is to run the re-bedding procedure
2. Easy but harder than that is to put some scratchy pads on
3. Harder than those two by far is to have them machined or replaced

I do what you do, which is I rebed them which is easily enough done if you
have a long downhill straightaway with no traffic or a highway straightaway
with no traffic.

In summary, the *crime* of people believing that the rotors actually warped
is that they never implement the correct long term solution. So they're
constantly complaining that their rotors warped.

 

[RS Wood]

clare@snyder.on.ca wrote:

You paid $90 to find that out. Consider it money well spent and move
on with your life.

Actually, I paid $100 to watch him and ask questions where I watched
EVERYTHING he did, since I want to do the job myself, some day.

I'll probably NEVER do it ... but I want to.

 

[RS Wood]

Xeno wrote:

Up to a point, I agree with you. Where I disagree is that most people
use them incorrectly (backwards) or size them inappropriately. They are
no different to an open end spanner when used correctly and, need it be
said, they are of a decent quality. When working on earthmoving
equipment, the most common adjustables I used were 15". 18" and 24". You
have no idea how many different spanners those three adjustables
replaced. In field work you need to cart *all your tools* with you. You
always look to minimise that load.

I should have made it clear that I was just kidding about making them
illegal.

I fully understand the *need* for the adustable wrenches, and I have a
Craftsman 3-piece set myself, which I almost never use.

I've probably used one about twenty times in forty years.

My beef is when people use them on "my stuff" when they have a perfectly
good socket wrench in the truck just 100 feet away.

 

[RS Wood]

clare@snyder.on.ca wrote:

There are things the dealer KNOWS about the car that the average
mechanic may NEVER know - things to look for to prevent problems from
ocurring. - like making sure the diff vent valves on RWD Toyotas are
free every time the car is on the hoist - meaning you virtualkly NEVER
need to replace axle bearings and seals - which will leak quickly if
the vent sticks.

The problem I've had with dealers is they lie like a rug.

I'm sure Indys lie like a rug too, but dealers don't know *more* because
they lie just as much.

More than a few times I brought cars to the dealer under warranty where
they said there was nothing wrong when, years later, I find out that it's a
common problem.

It has happened so many times, in fact, that I assume now that the dealer
is lying to me every time I go there.

If you want examples, I'll tell them to you, but my main point is that it
doesn't matter if the dealer knows more because they lie just as much or,
what they know doesn't trickle down to the guy who tests the vehicle.

This is Toyota and BMW and Infiniti and Nissan mostly though as when I had
American cars, they were used and therefore not under factory warranty.

I went to the Toyota dealership last week for a part and I was dismayed
totally at the lack of knowledge of the guy behind the counter.

So I UNDERSTAND you that the dealer *SHOULD* know better.
My experience is that they're worse than the Indy in terms of knowledge.

I have nothing against the dealer except one thing, which is why they're
called the 'stealer'. But that's a biggie.

Some are - some are not. I had the highest customer retention of any
Toyota dealer in Canada - usually well over 100% - which meant we
regularly serviced more cars than we sold - even after they were out
of warranty.

I'm not saying the dealer doesn't do a booming business.
I'm just saying that their prices are twice those of everyone else.
And their work is no better than anyone elses and the parts are the same.

The only other reason you go to the dealer is to buy parts that they might
stock where you need them now (e.g., you broke a bolt or forget a gasket
and you're in the middle of the job) but expect to pay more than double for
those parts than anywhere else.
Not always true. I've found many parts are the same price or cheaper
at the dealer than at the local jobber - and cheaper than buying from
Rock Auto and payinf shipping and brokerage.

Never gonna happen. Never. I can *always* find parts at Camelback online
for example, for my Toyotas that are about half the price of the local
dealer every single time.

For my bimmers, autohauzax and Max in Texas are always half the dealer's
prices for the exact same parts.

The dealer is NEVER the place to go for anything, other than something you
need out of inventory. Most of the time when I call ahead, they don't stock
the part, and then I give them a lecture to the tune of "how you gonna sell
anything if your prices are double and you don't even stock the part?".

They tell me they sell plenty of parts at their prices (just not to me).

 

[RS Wood]

clare@snyder.on.ca wrote:

> They only need to warrant it to the last converter and sensor.

That would be just after the cat, right?
I wonder why then, they made the last half of the system SS too?

 

[RS Wood]

clare@snyder.on.ca wrote:

Never seen 30W40 and 0W30 is a synthetic, so MUCH more coke resistant
than any conventional oil.

I was just making up numbers to show what I had meant by the spread, but
your point is perfectly valid that it can only be applied against the same
type of oil.

Use the oil recomended by the manufacturer
- in the case of my Fords and my daughter's Hyundai that is a 5w20 or
0W20 synthetic oil - which I change twice a year, which is less than
10,000KM per change

We've all seen the never-ending "what oil" threads, where, in the end, the
oil change interval matters more than what oil.

If we agree on that concept of coking:spread, then the question is how much
does coking actually matter and under what conditions does coking matter?
No - "spread" does not cause coking. Heat and time does. The
"spread" in conventional oil means the viscosity index will break down
faster than a narrow spread - it will loose it's ability to maintain
viscosity at temperature due to "shearing" of the long-chain polymers
used in VI improvers.

This is logically tenable.

High spread synthetic oils suffer a LOT less from this problem - and
in the vast majority of "coking" problems, the simple expediency of
changing the oil on the "severe service" schedule will totally
eliminate the ptoblem.

Also tenable in that changing the oil is more important than what oil.

Also, the use of the much more chemically
stable synthetic oil virtually eliminates the problem.

When I have a choice, which is usually at Costco, I take the dino juice
with the lowest spread but I agree that synthetic juice would be better
(for a couple of things) but in the end, the same cost since basically it
lasts twice as long and costs twice as much.

So it's a wash on cost, and on slipperiness, the dino juice works fine.

Even the "viscosity shear" is NOT a problem with 3000 mile or 5000km
oil changes.

Yup. Oil changes matter more than what oil we use.

 

[RS Wood]

Xeno wrote:

> Fractionally more than you. I watch the news on TV. That's it.

I get my news off the net.

But someone must be watching TV or cable (I don't have cable either).

My point is only that people spend time watching TV so they can't say that
taking your sweet time doing an oil change is wasted time if they're
wasting time watching "As the World Turns" all day.

 

[RS Wood]

Xeno wrote:

Just add gear to your list and delete pushrod. We are talking about
driving the *camshaft*. gear, chain, belt. There are a few varieties of
chain in use; single row, double row, hyvo.

Thanks. Had I done the job even once, I'd know more than I do, so I will
gladly take your word for it that there are three choices and we must pick
one of the three.
1. Gear
2. Belt
3. Chain

We have to pick one.
Which is the most reliable?

 

[RS Wood]

clare@snyder.on.ca wrote:

You are not drinking the coolade, but you are certainly falling for
the bullshit.

As I said with my lawnmower example, if someone makes a cheaper tool and
passes on the savings to me, I'm all for that.

I buy Craftsman and not SnapOn.
Is SnapOn better? Probably. Almost certainly. Right?
But I don't pay SnapOn prices. I pay Craftsman prices.

However, if someone sells me a cheaper hammer and then tells me it works
better in the snow at breaking ice, I'm gonna call him out on his marketing
bullshit.

I get it that a hammer can be made cheaper. I do.
I get it that a hammer's main job has nothing to do with breaking ice in
the snow, but that 10 days out of the year, the snow is deep enough when I
need to get to work that I have to break the ice with that hammer.

But for 355 days of the 365 day year, I'm stuck with that crappy handling
hammer. That's OK if the REASON I bought that crappy handling hammer was
because it was cheap.

It's not ok if I say that the crappy handling hammer handles better than my
hammer in the snow because losing handling 355 days of the year to gain a
smidge of handling in *deep* snow on the 10 days of the year that you have
to drive in it - is just not logical thought processes.

It's OK to admit FWD is cheaper.
It's not OK to lie about what it can do.

That's marketing's job.

 

[RS Wood]

Xeno wrote:

I remember $1000 but they didn't pass that on to the consumer in toto.

Cars are cheaper now than they were when I was a boy.

It would be interesting to look at the normalized price.

A car then, was $5K, and now is $50K so 10x doesn't seem too much off from
even given inflation.

I posit they lose handling.

They gain handling as long as they understand it's *different handling*.

Spoken like a true Marketing person!

My RWD car has never seen snow in 20 years except a few runs to Tahoe where
they legally required chains to get there.

Even when I lived in the snow belt ... deep snow was only on the road when
I needed the road for 1 or 2 days of the year, and at max, 10 days out of
365.

Think of that. Lousy handling for 355 days and just barely ok handling in
deep snow for the other 10 days.

The real FWD tradeoff was *never* handling.
It was profits.

Maybe FWD is better now ... but I think I'll have to go to my deathbed
before owning a FWD car... simply because I don't want to fall for the
marketing trap that everyone else easily falls into.

FWD works for me.

I have nothing against a cheaper tool. Nothing.
A car is a tool.
A FWD is a cheaper tool.

I just have something against someone seriously trying to tell me that his
cheaper lawnmower works better in the snow than does my more expensive
lawnmower.

I work off of logic.
Not marketing bullshit.

I never said I was always right though ... so if someone can show me fwd in
the best handling cars on the planet and at a cheap price ... count me in.

 

On Tue, 7 Nov 2017 00:46:35 +1100, Xeno <xenolith@optusnet.com.au>
wrote:

On 6/11/2017 9:36 PM, Vic Smith wrote:
On Mon, 06 Nov 2017 02:57:16 -0500, clare@snyder.on.ca wrote:


Only the stop-tech article is written by a pro (Can't open the
raybestos link so it's useless)

That "pro" says to replace brake fluid once a year.
I wonder how many people do that.
I never replace brake fluid unless I've got the system open.

Every two years at a minimum was what it used to be. The fluid is
hygroscopic and will absorb moisture out of the air or anywhere it can.

The new master cyls have a better atmospheric seal, so if you never
open the top to check or change fluid it's a bit better than it used
to be, but 2 years is still the recomendation.

 

On Mon, 6 Nov 2017 09:47:23 -0500, Ed Pawlowski <esp@snet.net> wrote:

On 11/6/2017 1:18 AM, RS Wood wrote:
RS Wood wrote:

I just am saying that nobody in this thread has given any logical reason
why rings would be "better" today than in the days of yore.

I think I got cranky.
Apologies.


As an alleged engineer you should be ashamed of yourself. Your thinking
lacks logic too, if you think a 1955 Chevy rings is the same as used
today.

https://upcommons.upc.edu/bitstream/handle/2099.1/22095/Designing%20and%20modeling%20of%20piston%20in%20combustion%20engines.pdf?sequence=1

Not to denigrate the GOOD engineers out there - but he sure thinks
like a typical engineer - - - One with no practical experience and a
"god complex" only exceded by orthopedic surgeons.

 

On Mon, 6 Nov 2017 10:00:28 -0500, Ed Pawlowski <esp@snet.net> wrote:

On 11/6/2017 1:13 AM, RS Wood wrote:
clare@snyder.on.ca wrote:

Pads, under extremes of heat, give off gases. It is the presence of
those gases *between* the pads and the disc that prevents the friction
from happening. The gases make the pads operate more like a hovercraft.
The slots provide a means by which the gases can quickly escape.
In a road going car, slotted rotors are probably overkill. Not so on
high performance vehicles.


100% correct - on both counts.

Marketing bullshit and applying racing specifics to street cars is classic
bullshit moves, where we've all had this happen to us a billion times.

Just show a reliable reference on the entire Internet ... just one ... that
proves that without changing anything else ... in a normally driven street
car ... which is what we're talking about here ... that any of that above
isn't anything other than marketing bullshit.

Just one reference from the entirety of the Internet.
You show it ... I'll read it.

Until then, it's marketing bullshit.


Doubt you'll believe it anyway.

https://ebcbrakes.com/articles/what-is-brake-fade/

There are principally 2 common types of formulation for a brake pad
friction material, organics and sintered metallics (there are also brake
pads known as ‘semi-metallics’ but these are a ‘hybrid blend’ of the two
aforementioned friction types and thus have properties that typically
lie somewhere in the middle). For more information on the different
brake pad constructions read our article ‘How to make brakes’.
Organic brake pads inherit their name from the organic phenolic resins
used to bind together the different compounds used in the pads
construction. There are countless different types of thermoset phenolic
resin, but they can all be generally considered to have a maximum
temperature up to which they are thermally stable. Above its intended
maximum operating temperature, just like any organic matter, the
phenolic resin used as the binding agent becomes altered by the heat and
effectively ‘boils’, expelling an appreciable volume of gas as it
degrades. (The actual technical term for this process is sublimation,
since once the phenolic material reaches the critical temperature it
jumps from its original solid state and changes instantaneously to a
gas, with no detectable liquid phase).

Basically almost smoke!!!

The dominant mechanism causing brake fade is this thermal degradation of
the phenolic resins and other materials in the friction lining, which
create a film of gas at the pad-rotor interface and effectively causes
the brake pad to skid off the disc. As these gasses build up at the
pad-rotor interface, they produce an appreciable backpressure which
creates an opposing force to the brake caliper that is trying to hold
the pads against the rotor. If there is no way for the gasses to escape,
the opposing force as a result of the outgassing can become large enough
to prize the pads away from the rotor, reducing the area of pad in
contact with the rotor and thus reducing braking power (i.e. brake fade).

And also making the pedal a bit "spongy" from trying to squeeze the
gas.