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

On Mon, 6 Nov 2017 04:49:21 +0000 (UTC), RS Wood <rswood@is.invalid>
wrote:

Frank wrote:

Chains are hardly ideal. Chains wear. The wear changes the pitch
between the links and the links no longer quite fit on the sprockets. It
turns into a self reinforcing cycle. More wear = worse fit, worse fit =
accelerated wear. Eventually the poorly fitting chain will jump one or
more teeth on the crank gear or start breaking the teeth on the cam gear.

What are our choices?
1. Chain
2. Belt
3. Pushrod

Anything else?
Pushrod can be gear or chain

The other effect of chain wear is retarded cam timing. The more worn
links between the crank and cam, the more the camshaft timing gets
retarded. I changed timing sets on conventional OHV engines and that
usually advanced the ignition timing from 5 to 10 degrees, suggesting
that chain wear had retarded the timing by that amount.

From a repair standpoint, how long do each typically last?
1. Chain ?
2. Belt ?
3. Pushrod ?

Chevy pushrod engines often took out the plastic timing gears in
under 100,000 km. Lots of timing chains on pushrod engines never made
100,00 miles.

I don't hear anyone talking about pushrods, so, all I see here are that
chains last a *lot* longer in general than do belts, where if either one
broke on an interference engine, expensive things can happen.

But I still prefer belts. Even on a tight package like a Dodge Neon with
the 4 speed auto, the replacement isn't too bad, once you know the
routine.

If the replacement isn't bad, then the belt isn't 'as' bad.

In the general sense though, belts, I posit, are bad news multiplied.
I try not to take things from the marketing-bullshit standpoint.
The belt is just a maintenance item like plugs

My take is always from the *why* standpoint.
Why did the automakers go to belts over chains?

Because in SO many ways they are better and they are not affected by
lubrication issues.

My supposition is that they did it to save them money.
No other reason.
You are wrong

The tradoffs are legendary where the owner is the one who loses in the end
calculation.

Not necessarily

Just like FWD cars and tricked-out cars are, to me, nearly worthless.

I love front wheel drive, especially in the snow.

Lots of cars are FWD that never see snow.

In the general sense though, FWD, I posit, is bad news multiplied.
I try not to take things from the marketing-bullshit standpoint.

My take is always from the *why* standpoint.
Why did the automakers go to FWD over RWD?
For many reasons which I have already given you.

My supposition is that they did it to save them money.
No other reason.
Nope,

The tradoffs are legendary where the owner is the one who loses in the end
calculation (particularly since deep snow is still on the road for what,
maybe 10 days out of 365?)
Not up here. and they make cars for world markets -

Anyone who mentions snow with FWD is falling directly into marketing hell.
Just like anyone who mentions belts are "quieter" and "lighter" is doing.

The sole reason for belts and FWD is to increase manufacturer's profits.
Everything else is marketing bullshit because the tradeoffs are legendary.

You can believe what you like - but my FWD cars get around in snow
al LOT better than my old RWD cars. Try driving a new mustang or
camaro in snow.

 

On Mon, 6 Nov 2017 04:49:25 +0000 (UTC), RS Wood <rswood@is.invalid>
wrote:

Ed Pawlowski wrote:

The $50 figure is about 30 years old. If it was accurate at the time is
would be double that today and there was still a lot of engineering and
new tooling to pay for. That said, I have no ideal today.

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

What irks me the most isn't that they make FWD cars, just like it doesn't
irk me that they make convertibles or muscle cars or economy cars or luxury
cars.

What irks me about FWD is that the hoi polloi do not UNDERSTAND what FWD
gets them.

I posit it gets them almost nothing.

Then the hoi polloi don't understand what they lose.

I posit they lose handling.

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.

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

 

On Mon, 6 Nov 2017 04:54:55 +0000 (UTC), RS Wood <rswood@is.invalid>
wrote:

Xeno wrote:

Hrm.+AKA- I thought that was done to lighten them -- bicyclists are
sometimes also called gram-shavers.+AKA- It provides better cooling too?

Removing mass reduces heat holding ability. The material removed does
not provide a gain in surface exposure. The real gain is providing a
path for the gasses coming off the pad surfaces to escape from between
the pad and rotor. Reduces the hovercraft effect.

I can spout marketing bullshit as well as anyone can.
I just choose not to.

If you can find a scientific study that proves for street cars that a
drilled/slotted rotor makes *any* difference over a solid rotor in braking
performance, let me know.

I'm all about logic.
Not for normal legal street driving

 

On Mon, 6 Nov 2017 16:25:31 +1100, Xeno <xenolith@optusnet.com.au>
wrote:

On 6/11/2017 3:48 PM, RS Wood wrote:
clare@snyder.on.ca wrote:

Some of the best rotors out there are Chinese - but also some of the
worst. Consistency is the problem

I can't argue but my point is that I've heard everything.
The problem is that the advice has to be both logical and actionable.

Saying "buy only Brembo or Meyle" is actionable, but not logical.
Saying "don't buy Chinese crap" is logical but not actionable.

For advice to be useful, it has to be both actionable and logical.
I've never heard that in rotors other than buy solid and don't buy
drilled/slotted rotors.

Other than that, there's no way for a person to tell if one rotor is gonna
be better than another.

Hence pragmatically ... a rotor is a rotor is a rotor is a rotor.

In some instances (virtually never normal street use) grooved and
slotted rotors DO provide better braking. We are talking competition
use, where the rotors are glowing red hot half the time, and the pads
are off-gassing like crazy - where even 100% dry DOT4 brake fluid
boils in the calipers. Under those conditions, rotors can warp - and
even fracture (in Rallye use I've seen red hot rotors hit an icy
puddle and totally fracture)

I'm never talking racing.
They drive on bald tires for heaven's sake in racing!


Yep, far better coefficient of friction - in dry conditions.


Actually, on SOME cases you can. Look at the consistancy of the fins
in the rotors, and the even-ness of the thickness of the braking
surfaces on both sides of the fins.

I'm not gonna disagree that we all can see the mark of good quality on some
things when we have two to compare in our hand, but it's too late if you
order on the net.

How are you gonna know the metallurgy?

You don't - that's the hard part - but when you are in the business
you get to know which suppliers stand up, and which don't. If you
know the suppliers well, they will tell you which ones they have
trouble with, and which ones they don't.

Yup. I have nothing against good suppliers. I use Brembo and Meyle but if
someone else gave me a rotor at a better price, I'd consider them too.

And some rotors DO WARP. Not many - but I've had at least a bushel
basket full of genuinely warped rotors in my 25 year carreer. Most
"warped" rotors are not warped - but some are. Some DRASTICALLY - to
the point the caliper moves visibly when the wheel is turned - and if
the sliders stick the pedal jumps and the steering wheel twitches.

That's not the measure of warp.
Warp is measured on a flat bench.
Just like head warp is measured.

Or with a dial indicator - on both sides - for comparison.

More often than not though, they are either pitted or have deposit
buildup, ot they have "hard spots" due to metalurgical inclusions

The only person who says their rotors warped that I will ever trust is one
who measured the warp just like you'd measure head warp.

Use to check for warp every time.

If they haven't measured it, it's not happening.
And nobody measures it.
So it didn't happen.

Some do. I did. I also taught apprentices to measure for it.

It "could" happen. But it doesn't (on street cars).
The problem is the temperature never gets hot enough.

It can under specific circumstances. See it most often on autos in very
hilly country.

Now they can be "warped" from the factory; but that's different (and rare).

Wrong tool. The one I'm talking about has tabs that fit into the
notches on the piston face to "thread" it in as you squeese. Can
sometimes get away with the $17 "cube" but the kit you KNOW is going
to work starts at about $35 for one of questionable quality, and goes
up very quickly from there (and IT won't turn back Mazda rear calipers
- they use a different system

I think we're talking about two different kinds of disc brake systems.
I had the Nissan 300Z which had the rear disc also as the rear parking
brake, but my bimmer has the rear disc and a separate rear parking brake.

The piston arrangement is different as is the way to retract them.

You don't *twist* pistons in disc brakes that I own that don't have the
parking brake as part of the disc brake itself.

At least I don't.


Never once in my life have I found a single person who has *measured* the
warp.

I have. many times.
How?

You know why?
They don't even know *how* to measure rotor warp.
They don't have the tools to measure rotor warp
A somple dial indicator tells the tale

Nope.
How you gonna tell runut from warp with a dial gauge?

Measure disc thickness at various points around the disc. If the
thickness doesn't vary, then any runout measured on the dial indicator
is warp. Verified by back and front runout comparisons.

By the way, thickness variation checks are part of a standard disc
inspection process.


- and sometimes one side is
straight, and the other side is not - parallelism warpage - where some
fins collapse and one side of the rotor "caves in" - 1 inch thick on
one "side" of the rotor, and .875 or something like that diametrically
across the rotor. - and sometimes virtually deead flat on both
surfaces - other times with about hald paralel and the other half
"sloped"

Now you're straining credularity.

(Hint: It requires a flat benchtop and feeler gauges and it's not hard -
but they don't know that because they didn't measure a single thing.)

That won't necessarilly tell you anything. The only way to KNOW is to
use a dial indicator properly.

How you gonna tell runut from warp with a dial gauge?

Compare measurements.

And that is where YOU are WRONG.
Many technicians measure brake rotors virtually every day of their
working lives.

On the entire freaking Internet, find *one* picture (just one) of a
technician actually properly measuring brake rotor *warp*.

Just find a *single* picture please. Just one.
On the entire freakin' Internet.

Find one.

Dealerships were then REQUIRED to buy an "on-the-car lathe" to true
up rotors.

That's not warp.
Nothing on this planet is going to fix warp.
There's not enough metal to remove.

Depends on the warp severity.

A wize man learns from the mistakes of others - a fool never learns
because he "never makes mistakes"

Which is why I wish I had done these half-dozen jobs:
1. Alignment
2. Transmission
3. Engine
4. Tires
5. paint

Done all, taught 1 thru 4 at a technical college.

Yes - you are right to the extent that MOST "warped rotors" are not.
But you are absolutely WRONG when you say they never warp in
street/highway use and anyone who says they have had a warped rotor is
lying and hasn't measured the rotor to prove it.

I never once said "never" but "almost never" which is different, and we're
only talking street, and I have references that back up everything I say
whereas you provided zero references for what you said.

I'm not here to argue opinions.
I only argue using logic.

Just read the references I provided and then provide some references that
back up your point of view.

The "Warped" Brake Disc and Other Myths of the Braking System
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

The 'Warped Rotor' Myth
http://www.10w40.com/features/maintenance/the-warped-rotor-myth

Warped Brake Rotors - Vibrating Reality or Internet Myth?
https://blog.fcpeuro.com/warped-brake-rotors-vibrating-reality-or-internet-myth

Stop the +IBg-Warped+IBk- Rotors Myth and Service Brakes the Right Way
http://www.brakeandfrontend.com/warped-rotors-myth/

Raybestos Brake Tech School, Part One: Rotors Don't Warp
http://www.hendonpub.com/resources/article_archive/results/details?id87

Notice amateur Woody is arguing with 2 former professional mechanics
and trade school instructors???? I'm done with him. A waste of time,
effort and breath. PLONK!!

 

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 ----

 

[Vic Smith]

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.

 

[Xeno]

On 6/11/2017 6:57 PM, clare@snyder.on.ca wrote:

On Mon, 6 Nov 2017 04:48:28 +0000 (UTC), RS Wood <rswood@is.invalid
wrote:

clare@snyder.on.ca wrote:

Some of the best rotors out there are Chinese - but also some of the
worst. Consistency is the problem

I can't argue but my point is that I've heard everything.
The problem is that the advice has to be both logical and actionable.

Saying "buy only Brembo or Meyle" is actionable, but not logical.
Saying "don't buy Chinese crap" is logical but not actionable.

For advice to be useful, it has to be both actionable and logical.
I've never heard that in rotors other than buy solid and don't buy
drilled/slotted rotors.

Other than that, there's no way for a person to tell if one rotor is gonna
be better than another.

Hence pragmatically ... a rotor is a rotor is a rotor is a rotor.

In some instances (virtually never normal street use) grooved and
slotted rotors DO provide better braking. We are talking competition
use, where the rotors are glowing red hot half the time, and the pads
are off-gassing like crazy - where even 100% dry DOT4 brake fluid
boils in the calipers. Under those conditions, rotors can warp - and
even fracture (in Rallye use I've seen red hot rotors hit an icy
puddle and totally fracture)

I'm never talking racing.
They drive on bald tires for heaven's sake in racing!


Actually, on SOME cases you can. Look at the consistancy of the fins
in the rotors, and the even-ness of the thickness of the braking
surfaces on both sides of the fins.

I'm not gonna disagree that we all can see the mark of good quality on some
things when we have two to compare in our hand, but it's too late if you
order on the net.

And only a total fool buys everything on the net. I can generally buy
off the shelf for close to the same price, with no hassle returns and
I get to see-feel EXACTLY what I'm buying.

How are you gonna know the metallurgy?

You don't - that's the hard part - but when you are in the business
you get to know which suppliers stand up, and which don't. If you
know the suppliers well, they will tell you which ones they have
trouble with, and which ones they don't.

Yup. I have nothing against good suppliers. I use Brembo and Meyle but if
someone else gave me a rotor at a better price, I'd consider them too.

Can't even BUY Brembo for my daughter's car.

And some rotors DO WARP. Not many - but I've had at least a bushel
basket full of genuinely warped rotors in my 25 year carreer. Most
"warped" rotors are not warped - but some are. Some DRASTICALLY - to
the point the caliper moves visibly when the wheel is turned - and if
the sliders stick the pedal jumps and the steering wheel twitches.

That's not the measure of warp.
Warp is measured on a flat bench.
Just like head warp is measured.

Not in the real world. On a large percentage of rotors doing it your
way is totally impossible. And my way (the industry standard) I can
measure warpage/runout ON THE CAR and know if it's a problem before
taking ANYTHING apart beyond moving the rim.

More often than not though, they are either pitted or have deposit
buildup, ot they have "hard spots" due to metalurgical inclusions

The only person who says their rotors warped that I will ever trust is one
who measured the warp just like you'd measure head warp.

If they haven't measured it, it's not happening.
And nobody measures it.
So it didn't happen.

It "could" happen. But it doesn't (on street cars).
The problem is the temperature never gets hot enough.

Now they can be "warped" from the factory; but that's different (and rare).

Wrong tool. The one I'm talking about has tabs that fit into the
notches on the piston face to "thread" it in as you squeese. Can
sometimes get away with the $17 "cube" but the kit you KNOW is going
to work starts at about $35 for one of questionable quality, and goes
up very quickly from there (and IT won't turn back Mazda rear calipers
- they use a different system

I think we're talking about two different kinds of disc brake systems.
I had the Nissan 300Z which had the rear disc also as the rear parking
brake, but my bimmer has the rear disc and a separate rear parking brake.

Really crappy system - sorry.


I've worked on everything from a moskovitch to a Rolls, with Jags,
Rovers, Toyotas, Fiats, Ladas, VWs, Nissans as well as just about
every North American brand

The piston arrangement is different as is the way to retract them.

You don't *twist* pistons in disc brakes that I own that don't have the
parking brake as part of the disc brake itself.

I'm talking in general - not the limited vehicles of your experience.

At least I don't.


Never once in my life have I found a single person who has *measured* the
warp.

I have. many times.
How?

You know why?
They don't even know *how* to measure rotor warp.
They don't have the tools to measure rotor warp
A somple dial indicator tells the tale

Nope.
How you gonna tell runut from warp with a dial gauge?
\Measure in more than 2 places -

- and sometimes one side is
straight, and the other side is not - parallelism warpage - where some
fins collapse and one side of the rotor "caves in" - 1 inch thick on
one "side" of the rotor, and .875 or something like that diametrically
across the rotor. - and sometimes virtually deead flat on both
surfaces - other times with about hald paralel and the other half
"sloped"

Now you're straining credularity.

No I'm not. Seen it many times

(Hint: It requires a flat benchtop and feeler gauges and it's not hard -
but they don't know that because they didn't measure a single thing.)

That won't necessarilly tell you anything. The only way to KNOW is to
use a dial indicator properly.

How you gonna tell runut from warp with a dial gauge?

Watch the needle move.

And that is where YOU are WRONG.
Many technicians measure brake rotors virtually every day of their
working lives.

On the entire freaking Internet, find *one* picture (just one) of a
technician actually properly measuring brake rotor *warp*.

The internet doesn't show EVERYTHING. What you know comes from the
web. What I know comes from tears in the trade (including teaching the
trade)

Teaching the trade, yes, bound to cause tears at times.

Just find a *single* picture please. Just one.
On the entire freakin' Internet.

Find one.

Dealerships were then REQUIRED to buy an "on-the-car lathe" to true
up rotors.

That's not warp.
Nothing on this planet is going to fix warp.
There's not enough metal to remove.

That is totally dependent on how much warp. And what, other than
"warp" will cause a rotor to develop "runout" if it is totally true
when installed.

A wize man learns from the mistakes of others - a fool never learns
because he "never makes mistakes"

Which is why I wish I had done these half-dozen jobs:
1. Alignment
2. Transmission
3. Engine
4. Tires
5. paint

Ond I've dome them all at least once.

Done hundreds and hundreds of alignments.

Yes - you are right to the extent that MOST "warped rotors" are not.
But you are absolutely WRONG when you say they never warp in
street/highway use and anyone who says they have had a warped rotor is
lying and hasn't measured the rotor to prove it.

I never once said "never" but "almost never" which is different, and we're
only talking street, and I have references that back up everything I say
whereas you provided zero references for what you said.

You have references I have experience.

Ditto. Been there, measured that. ;-)

I'm not here to argue opinions.
I only argue using logic.

Reality defies logic.

Just read the references I provided and then provide some references that
back up your point of view.

The "Warped" Brake Disc and Other Myths of the Braking System
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

The 'Warped Rotor' Myth
http://www.10w40.com/features/maintenance/the-warped-rotor-myth

Warped Brake Rotors - Vibrating Reality or Internet Myth?
https://blog.fcpeuro.com/warped-brake-rotors-vibrating-reality-or-internet-myth

Stop the +IBg-Warped+IBk- Rotors Myth and Service Brakes the Right Way
http://www.brakeandfrontend.com/warped-rotors-myth/

Raybestos Brake Tech School, Part One: Rotors Don't Warp
http://www.hendonpub.com/resources/article_archive/results/details?id87
Only the stop-tech article is written by a pro (Can't open the
raybestos link so it's useless)

The rest could be written by you - same level of cred. They are
written by enthusiasts who have read articles.

They are correct in most of what they say - but real warpage DOES
exist, because not all rotors are properly manufactured and stress
relieved and heat treated - like the problem Toyota had in the early
'80s, and many of the "crap" rotors in the aftermarket - as I have
explained before. In the "ideal world" they would never warp. Also,
not all rotors spend their life in "normal" conditions - other
problems in the braking system, or abuse, can cause a lot more heat
than normal driving - which is why the accurate stement is:

Overtightening wheel nuts or uneven tightening of same will cause
warpage of discs.

"Under normal operating conditions, properly manufactured and
installed brake rotors very seldom actually WARP. Poor quality rotors
can warp, as can rotors that are severely overheated due to abuse or
certain braking system falures. When you experience brake pulsation,
actual brake rotor warpage is UNLIKELY to be the problem - but
stranger things HAVE happened. Uneven friction material transfer due
to either poor intial bedding of the pads or improper use of the
brakes is much more likely, and some brake pads are more prone to
causing these issues due to their composition. In areas where winters
are more severe and salt is used on the roads some pad compostions are
more likely to cause problems - particularly the hard-spotting and
pitting of rotors due to localized overheating caused by uneven
friction material transfer. Many brake problems tend to be regional in
nature for this reason. Rustout of cooling fins of a rotor, for
instance, would be unheard-of in arizona or alabama, but fairly common
in the northeat and the "rust belt".


NEVER say never and ALWAYS avoid always.

--

Xeno

 

[Xeno]

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.

--

Xeno

 

[Xeno]

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.

--

Xeno

 

[Xeno]

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.

--

Xeno

 

[rbowman]

On 11/5/2017 9:48 PM, RS Wood wrote:

clare@snyder.on.ca wrote:

What doesn't last longer on a car nowadays?
Sometimes things like power lock actuators and some electrical
connections

I was watching a video by the MythBusters on how to get out of a car that
is sinking in a pond (pool in their case) where someone mentions to roll
down the windows ... heh heh ...

When's the last time you saw a roll-down window?

About 12 hours ago when I parked the car.

 

[rbowman]

On 11/5/2017 9:49 PM, RS Wood wrote:

I don't hear anyone talking about pushrods, so, all I see here are that
chains last a*lot* longer in general than do belts, where if either one
broke on an interference engine, expensive things can happen.

Unless it's a gear driven camshaft the pushrod design will have a chain.
Other than bikes I don't there are many gear drives because of the
fitting problems. My Harley has gears but they are factory matched.
Aftermarket cams tend to be noisier because of the wider tolerance.

 

[rbowman]

On 11/5/2017 9:49 PM, RS Wood wrote:

rbowman wrote:

There is more to it than that. FWD is more efficient than spinning a
drive shaft and rear differential. Bending power 90 degrees costs. FWD
also allows as much if not more passenger space in the cabin. If you
ever dealt with the transmission hump from hell you know what I mean.
Admittedly it's a moot point for me since I go for two bucket seats and
a center console but I don't haul a family around. FWD designs tend to
be lighter.

When you're chasing the EPA fleet mileage, FWD looks good.

But my point is that none of that was *why* they build FWD cars.

They make 'em for one reason, and one reason only.

The tradeoffs are legendary, especially in a group that has to DRIVE them
and REPAIR them.

Cheaper? No, you're wrong on that one.

 

[Ed Pawlowski]

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

 

[Ed Pawlowski]

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).

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).

 

[AMuzi]

On 11/6/2017 8:35 AM, rbowman wrote:

On 11/5/2017 9:49 PM, RS Wood wrote:
I don't hear anyone talking about pushrods, so, all I see
here are that
chains last a*lot* longer in general than do belts, where
if either one
broke on an interference engine, expensive things can happen.

Unless it's a gear driven camshaft the pushrod design will
have a chain. Other than bikes I don't there are many gear
drives because of the fitting problems. My Harley has gears
but they are factory matched. Aftermarket cams tend to be
noisier because of the wider tolerance.

My Corvairs are geared-cam.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

 

On Mon, 6 Nov 2017 18:06:57 +1100, Xeno <xenolith@optusnet.com.au>
wrote:

On 6/11/2017 5:53 PM, clare@snyder.on.ca wrote:
On Mon, 6 Nov 2017 14:51:59 +1100, Xeno <xenolith@optusnet.com.au
wrote:

On 6/11/2017 1:16 PM, clare@snyder.on.ca wrote:
On Sun, 5 Nov 2017 14:36:18 +0000 (UTC), RS Wood <rswood@is.invalid
wrote:

Xeno wrote:

If toe is last, then unloading, adjusting, reloading makes more sense.

Toe is last. Adjustments to camber will alter toe. Adjustments to toe
will not alter camber.

Thanks. The way I'll remember it is Caster -> Camber -> Toe.
Caster and camber are pretty well inter-related - changing one
changes the other on most non-strut suspensions. Struts are a whole
lot simpler.

Changing camber on a strut still changes toe.
I didn't say it didn't. camber has a lot less effect on camber, and
vice versa on a strut system than on a double wishbone system

That depends entirely on *where* you adjust that camber on the strut.

Since the caster adjustment can only be done some 16 or so inches
from the ball joint (have not seen an adjustable lower control arm
pivot in decades on a strut suspension) the difference in caster from
camber or vice versa is by necessity less than half what it would be
if the centers were 8 incges apaty like a typical double wishbone

 

On Mon, 06 Nov 2017 03:32:52 -0500, "Steve W." <csr684@NOTyahoo.com>
wrote:

RS Wood wrote:
Steve W. wrote:

Chains don't mean a lot when they drop them down to bicycle sizes with
small pins. Things stretch like cheap rope.

I think the only reason manufactures went to belts is to increase their
profits, so I wonder if there is any value to a belt AFTER you look at the
tradoffs.

The real question for a repair group would be the main factors:
1. Reliability of chain versus belt
2. Damage potential of chain versus belt
3. Repair hassle of chain versus belt

Let's ignore the marketing bullshit (e.g., lighter, quieter, etc.) for this
thread to concentrate on the reliability and repair-related issues.

As I already noted, I *wish* I had replaced a timing chain in my life, but
just like I've never owned a FWD vehicle (and I lived in a "snow state" for
decades), I have never had a belt car and I've never had a chain break on
me.

So I have no experience.
But....

I posit that:
1. The chain is *far* more reliable than the belt
2. Both can ruin an interference engine if they break
3. Repair hassle is probably about the same

The question is how long is the typical MTBF for a belt versus a chain?

Depends on the particular engine. Most belts are around 60K change
interval, and many are not hard to do. Then you have vehicles with
chains, a good design will go 2-300K with no real issues. The shitty
designs fail around 50-60K and do more damage than just the valves if it
drops into the lower sprocket on a stick that rolls a bit.
GMs 3.6 and some others use a VERY light chain that stretches and breaks.
"Garbage Machines"

 

On Mon, 06 Nov 2017 02:36:44 -0800, Vic Smith
<thismailautodeleted@comcast.net> 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.

I generally did when doing any major brake work (drums, rotors, pads
or shes) - just s thorough bleed.

 

On Tue, 7 Nov 2017 00:32:45 +1100, Xeno <xenolith@optusnet.com.au>
wrote:

The internet doesn't show EVERYTHING. What you know comes from the
web. What I know comes from tears in the trade (including teaching the
trade)

Teaching the trade, yes, bound to cause tears at times.

Took tech courses at high school - not typing!! - but you are right.
Tears of frustration

Snipped
Which is why I wish I had done these half-dozen jobs:
1. Alignment
2. Transmission
3. Engine
4. Tires
5. paint

Ond I've dome them all at least once.

Done hundreds and hundreds of alignments.

Likewize. Thousands of tires. likely at least a hundred transmissions
of different stripes, and between total rebuilds, head jobs, timing
chains, and other major internal work, several hundred engines.


SNIPP

You have references I have experience.

Ditto. Been there, measured that. ;-)