Stan shut off the engine and turned to Gus. "I rechecked timing and
point setting. All okay. Looks like the heat-control valve was frozen once
- there's a stain like penetrating oil around it. But it works now."
Gus nodded. "Raise the car, Stan."
Under the car, Gus found the twin mufflers and resonators apparently
sound. He tapped each muffler with a wrench. The two blows differed in
Gus came out. "I think a bad muffler is causing your trouble," he
told the driver.
"But there are no holes," the man protested.
"Holes aren't all that can go wrong with a muffler. One muffler is
roughing up your engine, and I think I can prove it."
The dark-eyed young man shrugged.
"We have tried all else. Okay."
"Change the right-hand one," Gus told Stan. Stan responded with a sly
Gus went back to the Olds, drained the chemical, flushed the system,
and refilled it. When he gunned the engine, ripples and suction could be
seen in the radiator neck, indicating normal pump action. He got in the car
and headed for a hilly region.
Surprisingly, the water temperature climbed as rapidly as before.
When Gus drove back into the shop, it was again near the boiling point.
Darby, who was waiting, looked glumly at the wisps of steam emerging beneath
"Sure wish I'd flown home." "You don't live in Washington?"
"Only go there on sales trips. I'm bringing this heap back for a
Gus had removed a small inspection plate in the radiator shield,
through which the drain petcock was reached. Now he put in a hand to feel
the radiator core, searching for cool areas that would indicate local
clogging. He felt no difference until his hand met something soft and
Taking a light, he slid under the grille and peered up at the radiator
core. He exhaled slowly, whistling softly. What he saw was a mass of
feathers - four dead birds, wings outspread as if in flight. They covered
more than half of the core's cooling area. Pulling them free, Gus dropped
the birds on the floor.
"Now I remember!" Darby burst out. "Coming around a bend fast, I ran
smack into a flock of birds. They flew up - I thought they'd all got away."
"These didn't make it. The grille openings are so big they went clean
through till they hit the core. Sorry I didn't spot them sooner."
"I should have tipped you off," returned Darby, getting out his
wallet. "You found the trouble the hard way."
Stan was killing time mounting the new muffler. Gus removed the
discarded one to a workbench, called the driver over, and proceeded to
hacksaw the casing apart. When opened, the two parts proved to be solidly
packed with a brownish-black mass, except for a small center passageway.
"There's what was fighting your engine," said Gus. "This sludge,
what's left of corroded baffles and wire mesh, choked the exhaust from the
right cylinder bank. At high speed, back pressure got bad enough to kill
power on that side. The clogged baffles also made the muffler noisy."
His audience now enlarged by Stan and the other stranger, Gus went
on. "Why did this one load up? Because with dual pipes the heat-control
valve channels exhaust from the right bank though the intake manifold
crossover for carburetor warmup, then out the left muffler. That muffler
gets hot fast, burning out the water, oil, and raw gas in the exhaust. Some
exhaust gets to the right-hand muffler, too - the valve doesn't cut it out
altogether. But this muffler doesn't heat up, so sludge, acid, and carbon
form in it.
"Once the engine's warm, the valve is supposed to open. Apparently
yours was frozen shut once, letting this muffler run cold a long time - and
sludge up - until somebody spotted the sticking valve and freed it. You'll
see the difference now."
"That will please my brother," said the driver. "he is just coming
from Puerto Rico and is anxious to drive on to see his girl here. I myself
came years ago as a chauffeur to drive such a car as the one that just
"No wonder you were interested in it," said Gus, with a glance at Stan.
"Yes. The owner brought me here, so that kind of car I always
"Your own will be ready in a jiffy now," promised Gus. "Won't it,
Red-faced, Stan nodded and fled to finish the job.
"Too many spy thrillers on TV - that's my trouble," grumbled Stan when he
and Gus were alone. "those two Latin types turn out to be innocent American
citizens, and the mystery man's a traveling salesman."
"You weren't all wrong. After all, we did find foreign agents, didn't
"What else would you call sludge like that, and four dead birds?"
asked Gus. "Besides, like the foreign agents you meant, they made a lot of
trouble as long as they weren't suspected."