Mercury Comet......Ouch!

[video:yahoo]https://www.motor1.com/news/597254/1300-hp-mercury-comet-brake-failure/[/video]

Good points made. All go and no stop sucks. Glad everyone is ok. Could have been worst.

more $$$ than brains in that build. then the loose nut got behind the wheel and drove it.

Turn the key off? Throw it in Reverse?

Maybe I missed it but did they mention the cause of the brake failure or what happened to the occupant(s) in the minivan that they rear-ended?

My takeaway was the throttle was sticking around 2,200 RPM and he was using the brakes to control the speed. Finally they overheated, probably on fire and failed. Little mention was made of the occupants of the mini van. If they find this video he may find the video should never have been made as negligence is indicated.

Might've also investigated to cause of the sticking throttle when it first happened

Hope he had good insurance

Looked to me like he either threw it into reverse or park, he threw the shifter forward and I heard that click-click-click that an auto trans makes when its told to do something it wasn't built to do.

There were warning signs that should have caused the whole deal to be put on hold until they could be checked out, but really, how many of us would have gone ahead and made the 5 mile run at 45 mph to 50 mph without much concern? I've done worse without any problems, that one wouldn't have fazed me either. I probably would have gone to the extreme right as soon as I knew there were no brakes, if there would have been enough time, but as it turned out, you take the path with the least amount of total damage, which would have been the single minivan instead of a line with 3 or 4 cars in it.

I asked this in the comments section- if by "Riding " the brakes they became overheated and thus useless.

Riding the brakes to control vehicle speed because the engine idle speed was too high? This is first order stupidity. It only turned one problem into two problems that then ended in three problems. If they had stopped and fixed the first problem, none of this would have happened.

Only the stupid ones.

I hope everyone in the other vehicles sues this guy back to the stone age.

Sorry poorboy But I have to agree

Reminds me a bit of this incident.

NAILED IT!!!! Fix the sticky throttle or maybe use neutral a bit more instead of the brakes. this almost qualifies for a Darwin award nomination

NAILED IT!!!! Fix the sticky throttle or maybe use neutral a bit more instead of the brakes. this almost qualifies for a Darwin award nomination [/quote]

I agree! The way he seemed to be stabbing the brake pedal made me think the pedal was going to the floor like a line broke or something failed causing brake fluid loss. The driver's action makes no sense to continue to ride the brakes while the car is pulling instead of throwing it in neutral and then applying the brakes when needing to slow down or stop. Also, heat related brake failure in my experience usually doesn't occur catastrophically. It usually happens where the brakes lose their effectiveness over time, and it gives the driver plenty of warning before complete failure. The driver was not a young guy and you would think he had enough experience not to continue to ride the brakes with a sticking throttle. Apparently not.

most people panic in a situation like this. Ignition off would have done the second most good. Not driving it till it was fixed would have been best.

Thought this was about the Comet - guess there were 2 knuckleheads out there putting others at risk. The Comet stunt is even worse.
Yikes - kinda sounds like he'd picked up the throttle or whacked it and then panicked. Sticking it in Neutral or killing ignition would have saved a lot of grief.
If it's a rod-style linkage - as opposed to a cable - there was likely a bind in the system. Or maybe there was insufficient return spring ?
Whatever the actual cause, I would think that would have been tested somewhere safe beforehand. And fixed.

You would not believe some of the stupid sh-t I've seen come through the doors that was real pretty but non drivable. Pro built trailer queens. Several had all kinds of awards and magazine articles on them
This guy was a definite inexperienced MORON. He/they blame it on old technology brakes, BULLSH-T. Overheating the brakes due to the stuck throttle and the idiot driving is the cause PERIOD. I wonder why two wives left this BS artist

Is this one of them built not bought cars everyone talks about? He had a [censored] rachet shifter, likely a [censored] gm style steering column that locks when you turn the key back too far, marginal brakes, and you would never drive with a sticking throttle. I about got killed in a streetrod with all these [censored] parts due to that locking column...I was riding when the dash wiring smoked. I will not drive or ride in them. Don't get me started on some of those mustang 2 based front ends with hemis sitting in them. Makes you appreciate how good a factory shifter, column, suspension and disc brakes in good repair really are.

IIRC, it was the front tires that were smoking, not the brakes; the brakes stopped the wheels & skinny tires, but Dude just pushed right on ahead.
Sketchy builds ? Yup, seen that all too often. We got a wrecked Ford truck street rod in once, guy said the steering failed. He was right - nothing was mounted properly, they'd actually used a bent S-10 frame, literally falling apart, wouldn't steer.
We also had to fix a bunch of other mechanical & fitment issues free, just to avoid any possible liability, even though it was the builder's hack chassis work.
Also had to re-do an A-body/440 swap for a guy; lots of stuff just slammed together, and barely useable...

Obvious blatant issues (stuck throttle, riding the brakes, 1300hp) aside. I lost all brakes last winter out of nowhere in heavy traffic on a busy 4 lane road. Yes your first instinct is to put it in park, it stops the car, thats what your brain thinks, but my first concern was getting off that road and I did, while pumping the s*** out of the pedal, brakes were barely doing anything by that point, it had blew a line in stop and go highway traffic just before and the drive thru for food rid the system of 95% brake fluid before heading back out with no idea yet, I thought it kept pushing through the brakes due to wind as it was VERY windy. Oh, it'll wake you up when you go for the brake and the pedal just drops to the floor. I got it into a wendys parking lot slow enough that putting it in park did stop it.

I was 2.5 hrs away from home, had it towed to a shop and it was fixed a couple days later.

Dumba$$ owner/driver replied on Youtube:

Well he's famous now, and
"I was still in the process of getting stated value insurance." then maybe he shouldn't have been driving it

Some are fortunate enough to avoid troubles through common sense, some learn through the misfortune of others, some must experience the joy of pissing on the electric fence, and at the bottom are those who feel the need to justify the experience of pissing on the electric fence and post video for the amusement of the former.

like the saying goes, "it ain't the speed that does ya in, it's the sudden stop that does it every time."

also, the old cartoon Ren and Stimpy, did a show titled "wizzing on the electric fence board game".

Need a voice over of Frank Rizzo from the Jerky Boys..."Shut it down Mike!"

That the owner/driver posted the above really isn't too smart.

If the driver of the van, or their lawyer, finds these comments, the owner/driver could be making a stupid situation even worse.

Mike.

To me, it is understandable that most laypersons don't understand the physics of friction brakes.
What is surprising is that so many "car guys" don't either - like the two seen in this car.

Brakes don't stop a car by "grabbing the rotor/drum to slow it down".

Friction brakes function by converting the kinetic energy of the vehicle mass in motion into heat energy in the hard parts, via friction...
...and then dispersing that heat energy into the surrounding air.

No matter the size/age/quality of the brakes, if you keep putting more heat into the hard parts without letting them disperse that heat into the surrounding air, the system will quit functioning.

Put the photo shoot on hold while you resolve the sticking throttle? Nope.
Well then.. kick the car into neutral periodically to quit accelerating? Nope.
Okay, so perhaps ponder exactly why you are smelling the brakes? Nope.

For added entertainment, the driver thinks that throwing the trans into Park is going to have a significant effect at the speed (note the brrrrrrrrrrrr of the parking pawl as it ineffectively grinds down).

Yep, the after-action reviewer thinks shoulder harnesses should have been used (um, how about you don't crash the car in the first place?)...
...and that they should have had a hand brake (to use an alternate method to add more heat into a overheated braking system).

To me, it is understandable that most laypersons don't understand the physics of friction brakes.


You really think most do not understand one of the most simple and basic brake systems?

Yes I do.

I have had countless conversations with customers back when I wrenched,
family members over the years,
and numerous acquaintances,
who all think that brakes work simply by pads/shoes "grabbing onto" the rotor/drum to "slow it down".

The physics of kinetic energy -> heat energy -> dissipated into air is beyond them.

Ask a selection of laypeople, and see for yourself the percentage who can explain "kinetic energy -> heat energy -> dissipated into air", versus those who take the "grabbing onto" path.

(Then again, maybe you surround yourself with a more intelligent cross-section of unwashed society.)

No mention of what exactly happened? I can't imagine the brakes boiling from riding the brakes unless he traveled some 200 miles or something.

I'm thinking there was a line broke and fluid loss. Although you'd think w/a trandem master cylinder, at least half of the brakes would still work.

My old auto shop teacher used to say: brakes, tires, steering. Everything else not as important.

Interesting how he never thought to TURN THE ENGINE OFF to stop the problem.

Small diameter lightweight drag race brakes are really easy to overheat. It wouldn't take long for that to happen trying to hold back that thing.

He probably got the brakes hot enough to boil the fluid.

You can run that shifter back down. It's called pull the release up.

1200 HP, skinny front runners on the front, huge tires on the rear, riding the brakes to overcome a throttle that is sticking at higher rpm, sounds pretty easy to overheat the standard disc brakes that were on the front of the car.

The video shows a lot of smoke coming from the front of the car just before the crash. Its entirely possible the brakes were functioning great, they may have locked up the front tires, but those small front tires were probably overwhelmed by the stuck throttle and 1200 HP turning those huge rear tires, pushing the car forward. Or it could have been total brake failure. We don't really know if the pedal went to the floor, or it just didn't give the pedal feel, and the stopping result the guy was expecting, and hoping for.

Turning off the ignition may or may not have shut the motor off if it was turning 2500 rpm, and 2 seconds before the crash, that may not have made much difference anyway.

Its pretty easy to say what we think would do in that situation, being an arm chair race car driver about to crash is quite different then sitting in the driver seat at that critical time. What we think we might do may not be what really happens. Talk is cheap. Quite second guessing the guy.

You know what we do know, based on his own words? That he knew he had a dangerous problem, and chose to drive on a public roadway anyway.



Any non-moron would've not driven the car until fixing the problem.

NAILED IT
Wonder if moron's riding the brakes are related to global warming LOL

For anyone else questioning the overheating of brakes affecting their ability to function might ask why they have runaway truck ramps on the major roads through mountainous terrain

May not take much to have the linings and/or metal surfaces become glazed-over.
That will produce excessive heat without any, or minimal braking action.

Bottom line IMO is he "boiled" the brake fluid from riding the brake pedal. Brake fluid in common hydraulic brake systems doesn't circulate so the pockets of brake fluid that pushes the caliper pistons is the first to fail and turn from a liquid to a gas. At that point the brake pedal goes right to the floor just as you can hear in the video. You can pump all you want but they are done. The brakes would have been fine for the most part had the driver not used them (riding the brake pedal) to control a vehicle with a sticking throttle......dumb @$$, Brakes take kinetic energy and convert it to heat energy and most brake systems can dissipate that heat energy without boiling the non-circulating brake fluid. Too much heat energy from riding the brakes and fail. I could get a rear brake disc and metallic sintered brake pads glowing in less than a minute on the dyno and the brake pedal would drop (no pedal pressure) and in most cases the brake line would start to melt and disconnect from the banjo fitting where it attached to the caliper. The guys in the race shop wouldn't believe me so the bets were on.................yep less than a minute to fail by riding the brake pedal.

that pic is scary indeed !
that reminds me of when i used to watch nascar on tv during a night high bank short track race. the camera would focus on the wheels in the turns, glowing red. they seemed to cool off on the short straight stretch, then glow red again in the turn.
i wonder what brake fluid those guys used ?

IF the guy used drag race brakes on the car, they are not intended to make the car stop better. Their purpose is to be light. On a blown street car that is not a good choice.

Uhhh, yeah, I think that is the simplest way to explain it. You can use more complicated words to describe the action of "braking" like.....The clamping force of the caliper or expanding of the drum shoes create friction which results in heat which is dissipated, etc.

A car can be first started and backed out of the driveway and the brakes will stop the car even though almost no heat has been generated or dissipated yet. The brakes did stop the car by creating a friction between the brake pads/shoes and rotor/drum.
Sometimes people are trained to understand matters in a way that falls far outside the way that is simple to explain to others.
An A/C guy I know gets all pissy when someone says that air conditioning cools the air. He is always quick to state that NO, the air conditioning removes the heat from the air, making it cooler.
So what...? The result is the same.

And a vacuum is a push, not a pull.............................................

Kern Dog wins the round using his go to move; Common Sense.

They use a very high temp (boiling point) brake fluid and heat insulators between the caliper pistons and the brake pads. We used phenolic caliper pistons or "buttons" in the center of the aluminum caliper pistons as stand offs to keep the heat from migrating into the pistons and boiling the brake fluid in the caliper. The brake would still work on the bike in the photos IF I would still have brake pedal pressure but once the fluid turns to a gas you can no longer force or push the brake pads against the disc. Carbon pads and discs will still stop even glowing hot as long as you have fluid pressure to push them against a friction surface (disc). 68HemiB's post is a perfect summary of how brakes work But IMO what happened to the car we're talking about the driver riding or using the brakes to control a sticking throttle he boiled the brake fluid and lost all pedal pressure and at that point you are not going to make any friction and stop or slow down at all. Other factors are the quality and age of the brake fluid in the car and if it has been overheated before and if it has then the threshold for failure gets even lower. Bottom line he cooked the brake fluid and lost pedal pressure. "Energy can neither be created or destroyed" And one cannot say that NO heat or thermal energy is generated in a friction brake system even backing out of the driveway, it has to even if it's one degree that's how it works. Kinetic to Thermal. Thought about making water cooled calipers to keep from boiling the brake fluid but I bet someone already thought of that. I know we make cooling fins for them.

Mike

(note the brake pads are glowing hot too and the heat insulator between the brake pad and caliper in not but it still boiled the brake fluid in this case.)

pretty great reply Mike.
those two other pictures were interesting as well.
as to the doofus this is about, all i can say is : "high performance car, low performance driver"..............[insert your preferred descriptive words here]
if it were me, and the problem were known, i would not drive the car until it was fixed.
reminds me of a guy that stopped over one day. he has a "starskey and hutch" torino.
he said the steering was acting funny, so he took it out to the interstate to see if it still happened at high speed.
one look under the hood, and i found the rag joint from the column to the box had just a TINY piece of rubber holding it together !
after seeing that, i told him he was an a$$ for driving his car that way !
luckily, the local parts place had a joint in stock, and he didn't leave until i fixed it for him. this isn't the first time this guy pulled stupid stunts.
for some reason, he thinks you need 17 floor mats to "protect" the carpet, then says "occasionally" he has to rearrange them so the gas pedal doesn't stick............
good grief..........