Waiting on the curb for the light Gus
Wilson watched the long line of cars start their climb up the steep Center
Street hill. It was the usual Sunday afternoon traffic jam.
Suddenly, the line stopped. A
sedan, just at the foot of the hill, was having trouble. Horns tooted,
gears growled, and men shouted. In spite of the plume of smoke that
puffed rhythmically from its exhaust pipe, the car could not budge. At
last, with a clanking and scraping of bumpers, the car behind pushed it
around the corner and out of the way.
Gus shouldered his way through the
small crowd that had gathered around the stalled car and spoke to the
driver.
"My name's Gus Wilson," he said.
"I run a garage and I thought maybe I could give you a hand. What's
your trouble?"
"Blamed if I know," the man replied,
fiddling nervously with the gearshift lever. "Everything was all right
until I started up that hill. When the light changed, I put her in
low, let out the clutch, and stepped on the gas. She went ahead for a
few feet, then the motor started racing and she stopped."
"Mind if I try?" asked Gus.
"You're on level ground now, and she may act better."
Gus edged into the driver's seat and
stepped on the gas. "Sounds swell!" he commented, as the motor raced.
"The gear shift seems to work all right too."
The veteran mechanic shifted into low
and cautiously let out the clutch pedal. At first, nothing happened,
but as he fed the motor more and more gas, the car moved unsteadily ahead
like a snail.
"I'm sorry, mister," Gus said, shaking
his head, "but your clutch is shot. It's slipping so badly it won't
drive the wheels."
"The clutch!" echoed the man.
"Gosh, now I am in a pickle! Something like this would have to happen,
when I'm sixty miles from home!"
Gus pulled his watch from his pocket.
"It's just two o'clock now. Why not let me coax the car over to the
Model Garage. If we work fast, and have any luck, we ought to be able
to fix the car up by five."
Once Gus had donned his overalls and
cap, he wasted no time. In less than three quarters of an hour he
dropped the transmission, loosened the clutch cover, and had the main clutch
assembly out on his workbench.
"So that's what a clutch look like,"
exclaimed the car owner. "Sort of a combination of springs and plates
isn't it?"
"That's right, and it's those springs
and plates that hook up your motor with the main drive shaft when you let
out the pedal. This particular clutch is what is called a single
dry-plate type. See this?"
Gus held up a thin metal disk about
ten inches in diameter; on each side it had a flat ring of hard, fabric like
material.
"That's the clutch disk. It's
fastened to the shaft that drives your transmission, and rides between the
inside of the flywheel and a heavy plate attached to these springs.
When your clutch pedal is out, the springs force the pressure plate toward
the flywheel, clamping the clutch disk in between. Naturally, it binds
against the flywheel and turns each time the flywheel is turned by the
motor.
"Now," continued Gus, stopping for a
breath, "when you push your clutch pedal down, the springs are compressed,
the pressure plate is moved away from the flywheel, and the clutch disk is
free."
"But what's this stuff for?"
interrupted the car owner, pointing to the ring of fabric on one side of the
disk. "Looks like brake lining."
"And it is something like brake
lining," agreed Gus. "That's the friction surface that makes contact
with the flywheel and the pressure plate when the clutch pedal is all the
way out. And, incidentally, it's the one thing that wears in a clutch
and causes trouble.
"Take your case for instance. Your
motor ran swell, but it wouldn't drive the rear wheels on a hill. Why?
Look at these friction surfaces. They're worn down smooth, and are
only about half as thick as they should be. Of course, it wouldn't
bind between the pressure plate and the flywheel. It slipped; it
couldn't take hold.
"Have you ever driven a car that
wouldn't start up without almost jerking your head loose? That's
because the clutch takes hold too suddenly. The adjustment may be too
tight, the clutch surfaces may be glazed over, or the rivets that hold them
in place may be sticking out so that they grab."
"Gosh, isn't there some way to take up
for the wear in a clutch without taking it all apart?" asked the car owner
as he gazed at the assortment of parts on the bench.
"Sure. On most clutches you can
adjust the pedal to make up for normal wear and tear, but your clutch is
beyond that. The only thing left now is to put on new friction rings.
"Clutches are funny things. The
more they slip, the more they wear. From the looks of yours, it's been
slipping a long time. If you'd had it adjusted four or five months
ago, this might not have happened."
"But how in the world would I know it
wasn't working right?"
Gus shrugged his shoulders. "You
can't tell how much air is in a tire by looking at it, but you can have it
checked at your garage, now and then. Besides, if you know where to
look for them, you can find plenty of symptoms of a slipping clutch.
"It generally shows up first in
starting; the motor will race, but the car won't move ahead very fast.
Then, sometimes, on hills, the engine will suddenly speed up without making
the car go any faster.
"You can tell a lot, too, by the feel
of the clutch pedal. If you find it doesn't take hold 'til it's almost
all the way out, it's usually a sign something's wrong.
"Noises are another warning. When a
clutch chatters, chances are the pressure plate is warped or one of the
springs is weakening. A squeaking clutch, generally, comes from lack
of oil in the throw out bearing, and a rattle means one of the moving parts
is loose or a spring is broken.
"Of course," confirmed Gus, working as
he talked. "A slipping clutch doesn't always mean wear or broken
parts. Sometimes oil or grease gets on the clutch facings and makes it
slip. When that happens, the best cure is a gasoline bath. Turn
the motor over slowly and squirt the gas over the disk with a grease gun or
an old garden spray."
"But I thought some clutches were
supposed to run in oil."
"Some are, but the majority of modern
cars use clutches which have to be dry, to work. Except for a few that
have more than one friction disk, most clutches are just like yours."
"Gosh!" The car owner wagged his head.
"This clutch business is all news to me. I never gave it a thought
until today."
"And that's where most of the trouble
comes in," pointed out Gus. "A clutch, to most drivers, is just
something you have to fool with every time you shift gears. Most
clutch troubles don't come from normal wear; they come from abuse."
"By the way," the man said when Gus
announced that the job was finished, "you haven't tipped me off to any
tricks I can use to save my clutch."
"Forget about the tricks, and use a
little common sense," advised Gus. "Just keep your foot off the clutch
pedal as much as possible. Don't give the car too much gas when you're
starting up. Don't slip the clutch to hold your car when you're
stopped on a hill. And let your serviceman look at the clutch now and
then. If a slipping clutch is caught in time, it can be adjusted in a
jiffy."
END
