The motor ran smoothly again--a fact which Bland was too scared to notice.

He gasped when Johnny turned back toward the huts, but beyond a protesting look over his shoulder he gave no sign of dissent.
They started to climb, got fifty feet from the ground and the motor began to spit and pop again.

Then it stalled completely, and they came down and went bouncing over the uneven surface and stopped again, a rod or so nearer the willows than before.
Several scuttling figures left that particular hiding place like rabbits scared out of a covert, and Bland took heart again.

A few minutes he spent crouched down in the cockpit, watching the willows, and when nothing happened he ventured forth, armed with pliers and wrench, and went at the motor.
"Sounds to me like poor contact," he diagnosed the trouble.

"Like the breaker-points are roughened, maybe.