Free High-Speed Showdown by Franklin W. Dixon

suddenly the flames vanished.
    Joe and Dennis continued to spray the engines with foam for another thirty seconds or so. Then, as if on signal, they both stopped at the same moment. The only sound was the slap of the waves on the side of the boat and the muffled putt-putt from Sleuth’s idling motor.
    â€œWhew!” Dennis said, wiping his forehead. “That was nasty. Thanks for your help, Joe.”
    â€œI think we skip the time trials,” Miguel observed.
    â€œI think you’re right,” Dennis said in a choked voice.
    Joe asked, “Does that mean you’re out of the race?”
    Dennis shrugged and continued to stare down at the engines. “It depends on how much damage was done. If we can get the engines back in shape fast enough, we can still run in one of the elimination heats tomorrow and get a spot that way.”
    â€œWhat happened?” Joe continued.
    â€œI’d like to know the answer to that one myself,” Dennis replied. “You think you guys could give us a tow back to the dock?”
    Joe swallowed. He was ready to try, and he knew Frank would be, too. But taking a forty-foot boat under tow in a crowded harbor was no job for casual boaters. Luckily, before he had to answer Dennis’s request, a tugboat approached. Its captain had seen the smoke and offered to help. Miguel scrambled up to Adelita ’s bow, caught the towline, and fastened it securely to the bow cleat. Then he raised his clasped hands over his head to signal to the tugboat crew that the tow was securely attached.
    The note of the other boat’s powerful diesels rose in pitch. The thick rope came dripping out of the water and straightened out. For a long moment, nothing seemed to happen. Joe realized that the line must be stretching. Would it hold? Then Adelita started to move.
    Joe looked around. Frank was following at a safe distance. He caught Joe’s glance and waved. Now that the emergency was past, Joe began to wonder. Had the fire been an accident? Or was it part of a real and increasingly dangerous plan to wreck the regatta?
    Once back at the dock, Joe helped Dennis and Miguel maneuver Adelita into its slip. Frank tied up Sleuth nearby and joined them, just as a blond guy in white coveralls came running up.
    â€œDennis!” he exclaimed. “I heard what happened. Are you two okay?”
    â€œWe’re fine,” Dennis replied. “I’m not so sure about the engines, though. Joe, Frank—meet Pavel, one terrific mechanic.”
    The Hardys said hi to Pavel, who nodded briefly and went immediately to the boat’s engine compartment. Pulling a small, powerful flashlight from a side pocket, he shone the beam on the soot-blackened engines.
    â€œIt’s not too bad, thanks to the automatic fire-extinguishing system,” Pavel said after a few moments. “The fuel cutoff worked, too, I see. That’s good. One of the fuel lines became loose. If the flow had not stopped at once, we’d still be watching the flames.”
    â€œA loose fuel line?” Dennis questioned, his voice heavy with disbelief. “Didn’t you check those fittings when you tuned the engines this morning?”
    Pavel looked up over his shoulder at Dennis. “Yes, I did. They were tight,” he told him.
    â€œThen how . . . ” Dennis fell silent. It seemed to Joe that his face turned pale.
    Frank asked, “Was there someone with the boat all morning?”
    â€œWhat? Oh—” Dennis thought for a moment. “Let’s see, we came back from that practice run where Joe saved our bacon. We hung around for a while. Then Pavel showed up to give the enginesa final tweak or two. Miguel and I watched him for a little while. Then we went up to the inn to get a bite to eat. When we came back, we ran into you and Joe. So yes, somebody was here the whole time.”
    Joe noticed Pavel stare down at the ground, twisting his hands together. “You