What are some car-repair jobs you always wished you could do but have never done?

On 7/11/2017 2:08 PM, wrote:
> On Tue, 7 Nov 2017 00:55:08 -0000 (UTC), Frank >
> wrote:
>
>> On Mon, 06 Nov 2017 04:49:21 +0000, RS Wood 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?
>>>
>>>> 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 ?
>>
>> Depends what you mean by "how long does it typically last?"
>>
>> Timing sets on OHV engines typically wouldn't totally fail at under
>> 100,000 miles. Most of those sets were used in the days when cars were
>> junked at about that mileage. Alot of those cars were junked because the
>> timing set failed.
> I replaced a lot of timing chains and spockets on OHV engines
> particularly The GMs with the plastic cam sprocket
>>
>> But I'd guess timing set wear would retard cam timing around 1/2 to 1
>> degree every 10,000 miles. If we set an arbitrary failure spec of, say 3
>> degrees, then the set would have gone out at 30 to 60,000 miles. Of
>> course, the car would run even if the camshaft were retarded more than
>> this and the driver usually became acclimated to the poorer performance
>> and gas mileage.
>>
>>> 2. Belt ?
>>
>> I don't know. My car requires belt replacement every 100,000 miles or
>> six years. I replaced the belt at eight years and it looked perfect.
>> There's no significant timing change as the belt ages, until it fails.
>> An insignificant number fail before the required maintenance time.
>
> Except the little Chevy Optima? where virtuallly NONE made it much
> bast the recommended change point and many failed well before. Bad
> korean belt.
>>
>>> 3. Pushrod ?
>>
>> I don't know what you're getting at. Most US pushrod engines drive the
>> cam with sprockets and a chain. A few used gears. A few antique
>> motorcycles used tower shafts and bevel gears. Maybe some auto engines?
>> dunno.
>>
> The early Riley, for one.

Rolls Royce Merlin and Kestrel engines.

http://spitfirespares.co.uk/Merlin%2...storation.html

http://www.avrosystems.co.uk/bomber/...earsmodded.jpg

Not a chain in sight. ;-)

I had an ashtray made out of the piston of one.

The long head studs made very good pry bars.

The alloy those engines were made from was nothing like the crap alloy
you get now.


<snip>


--

Xeno

On 7/11/2017 3:19 PM, RS Wood wrote:
> Xeno wrote:
>
>> It is the balance of the torques.
>
> Remember, we covered this in detail DECADES ago.

You did, I didn't. Wasn't here decades ago.
>
> Everyone confuses *runout* with *warp*.
>
> They're not the same thing.

I am well aware of that.
>
> One requires *permanent bending* of the rotor.

That too - and I've seen it, experienced it. YMMV since you haven't been
actively involved in the trade.
>
> You have to do that without snapping the lug bolts.
>
> Two logical questions HAVE to be considered:
> 1. How much torque *can* you apply?

Quite a lot you will find. Wheel nuts are torqued way below their
maximum capacity but, unfortunately, there are quite a few rock apes out
there in the trade who have no idea of their strength or how to use a
torque wrench.

> 2. How much torque does it take to *bend* a rotor?

That depends on the rotor and the hub it is attached to.
>
> Without logic - it's just politics or religion.
>
>>> QUESTION FOR YOU THAT WE ASKED 30 YEARS AGO OF OTHERS:
>>> Q: How much torque on one bolt would it take to bend a rotor?
>>>
>> Had it happen on a Mazda I owned. I wasn't happy and complained
>> bitterly. You can put a lot more torque of a wheel nut than is required.
>
> There is a huge difference between runout and warp.
>
> Are you talking warp?

Warp! Defintely warp. Once the wheel nuts were loosened and correctly
tightened, most warp disappeared but sufficient remained to cause a
slight steering shimmy. And, yes, steering shimmy is the effect you get
from warped discs.

> Or runout?
>
> I'm only talking pure logic here.
> Not religion.
>
I'd have said your *logic* comes entirely from book learning and not
from the real world of the trade I spent 50 years involved in.

--

Xeno

On 7/11/2017 3:21 PM, Frank wrote:
> On Sun, 05 Nov 2017 14:42:50 +0000, RS Wood wrote:
>
>> What fails rotors the most (by far) is thickness.
>
> Around here, it's the rust that thins the rotors. The braking surfaces
> don't rust significantly, but the rust just flakes out of the vent holes.
>
> Replacing rotors every other brake job is about right in the rustbelt.
>
I used to replace Land Rover brake drums every second set of brake
shoes. Might add, in that hostile environment, brake shoes lasted a
maximum of 4 weeks on a good run.

--

Xeno

On 7/11/2017 3:41 PM, Frank wrote:
> On Sun, 05 Nov 2017 05:47:02 +0000, RS Wood wrote:
>
>> Never once in my life have I found a single person who has *measured*
>> the warp.
>
> Does eyeballing it count? I bought a used car in which I could see about
> 1/16" of warp as I rotated the rotor and looked through the top of the
> caliper. It was one of those cars with the rotor captured behind the hub
> and the shop price for the repair probably contributed to the previous
> owners desire to get rid of the car.
>
That's when you get cars cheap - but only if you can fix the issue
yourself. ;-)

--

Xeno

Xeno wrote:

> I'd have said your *logic* comes entirely from book learning and not
> from the real world of the trade I spent 50 years involved in.

Everyone here is talking about runout which is *different* than warp.

I owned Chrysler & Dodge, as you know.

As you may know, the lug bolts, in those days, were reverse threaded on one
side of the car.

I snapped a few before I realized it (I was just a kid at the time).

The amount of torque you need to *bend* a rotor would snap a lug bolt well
before you ever got close to permanently bending a rotor.

Doesn't anyone here think logically?

Frank wrote:

>> Never once in my life have I found a single person who has *measured*
>> the warp.
>
> Does eyeballing it count? I bought a used car in which I could see about
> 1/16" of warp as I rotated the rotor and looked through the top of the
> caliper. It was one of those cars with the rotor captured behind the hub
> and the shop price for the repair probably contributed to the previous
> owners desire to get rid of the car.

Doesn't anyone here know the difference between runout and warp?

Frank wrote:

>> People who believe in marketing bull**** never follow basic logic.
>
> Since you've decided how I'm thinking, what's the logic in responding?

The issue with logic is that it's unassailable.

> OK, let's say it's 1% of the days. I don't want to be needlessly late
> on ANY of those days. More than that, the FACT that traffic is now
> flowing more smoothly on snowy days makes driving less stressful.

So that means that you are willing to have worse handling for the 99% of
the time that you drive so that you can have better handling (which only
happens in *deep* snow) 1% of the time.

That's fine.
I just wanted you to think logically.

> I will say that, last year, I was driving home on a snowy day. Traffic
> was light and what traffic there was, was making safe progress. Some
> dumbass decided to pass me fast on the right, lost traction on his RWD
> vehicle and spun his car across three unoccupied lanes and smacked his
> passenger side wheels against the curb on the opposite side of the road.
> Pretty uncommon now, but things like that used to happen frequently in
> the RWD days. I don't miss it.

Someone should clue you in to the fact that an anecdote does not make
science.

I had a friend of my mom's who was talking to her brother and he was then
worried about his girlfriend who drove a red car and then he had an
accident because he saw a red car in front of him.

I just proved that red cars cause accidents as much as you proved the same
with RWD in the snow.

Your anecdotal "bro" science is for idiots, politicians, and priests.
The rest of us use logic. And facts. And statistics.

>> That's the percentage you're getting the *other* handling out of FWD.
>
> Fine. It makes driving safer and smoother a few days out of the year.
> It is NEVER a detriment to me. For me, there is NO handling downside.

You're talking about driving in deep snow for heaven's sake.

Do you really think your FWD handling is *great* in deep snow?
Why not just put chains on RWD for those days you're in deep snow?

Then you could have good handling 99% of the year and sufficient deep snow
traction when you need it 1% of the year.

Doesn't *anyone* on this newsgroup think logically?

Anyone who buys FWD for handling has already proven they can't think
logically.

>> You may not want to answer the question because it's too logical a
>> question for someone to ask about handling tradeoffs given your
>> extremely carefully cherry-picked hand-crafted situations versus normal
>> situations.
>
> For me, there is no trade off. Whatever difference there is, is
> positive. I didn't need any marketing bull**** to convince me of the
> superiority of FWD. All it took was getting through the winter. And I
> like the extra interior room, too.
>

I completely understand everything you say because you can't say anything
that everyone else who falls for the marketing bull**** doesn't say because
it's *exactly* what the marketing bull**** *told* you to say.

Don't feel too bad. Most people fall for the marketing bull****.

They, like you, can't think logically.
Just don't blame me for telling you the truth.

On Mon, 06 Nov 2017 15:30:43 +1100, Xeno wrote:

> Lots of traps for the unwary in that little task.

No doubt. I had a friend who worked at a transmission shop and also
rebuilt transmissions in his garage. We'd hang out, talk car repair and
he said he had to redo his first few rebuilds. Biggest problem was the
effort to pull and replace the trans.

Odd thing was, he hated working on carburetors.

I expect I'd just install a good junkyard trans and rebuild the
original. I have no expectation I'd get it right the first time.

On Tue, 07 Nov 2017 05:24:03 +0000, RS Wood wrote:

> Then you could have good handling 99% of the year and sufficient deep
> snow traction when you need it 1% of the year.

With FWD I have good handling 100% of the year. Rear wheel drive
handling is OK 99% of the year.

What logic says that 99% is better than 100%?

What logic says that continually installing and removing tire chains to
get that 99% to 100% is better than being happy with the 100% without
chains?

On Tue, 07 Nov 2017 05:09:36 +0000, RS Wood wrote:

> Frank wrote:
>
>>> Never once in my life have I found a single person who has *measured*
>>> the warp.
>>
>> Does eyeballing it count? I bought a used car in which I could see
>> about 1/16" of warp as I rotated the rotor and looked through the top
>> of the caliper. It was one of those cars with the rotor captured
>> behind the hub and the shop price for the repair probably contributed
>> to the previous owners desire to get rid of the car.
>
> Doesn't anyone here know the difference between runout and warp?

OK, please tell me. The rotor ran true for about 270 degrees of
rotation. Then it dipped inside about 1/16" of an inch. Never saw
anything like it before or since.

Warp or runout?

I say warp, but I see NO practical difference. Should warped discs be
machined differently than discs with runout?

Should discs with excessive warp be tossed in a different bin than discs
with excessive runout?

So, also please tell me the PRACTICAL difference between warp and runout.

Those of us who don't think logically need to know.