On August 17, 2001, about 1715 Pacific daylight time, a Cessna 172-A, N7198T, made an off airport forced landing following a loss of engine power about 2 minutes after departure from Pine Mountain Lake Airport, Groveland, California. The pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The airline transport pilot, the sole occupant, sustained minor injuries; the airplane sustained substantial damage. Visual meteorological conditions prevailed for the personal local flight, and no flight plan had been filed. The pilot stated that he preflighted the airplane, drained fuel, and completed an extensive run-up. He taxied to the fuel pumps and added over 18 gallons of fuel. He did another run-up and departed. About 75 feet above ground level (agl) the engine sputtered and lost power. The pilot was unable to regain power so he attempted to land on a dirt road. The left wing contacted up sloping terrain; the right wing contacted trees and separated from the airplane. Air Yosemite in Colombia, California, inspected the airplane. Mechanics observed that all engine controls were secure and functioning. The carburetor air box was intact and functioning. The magnetos were timed to within 1 degree of each other. The mechanic did not recall any discoloration on the spark plugs that garnered his attention. All cylinders except cylinder No. 5 had compression greater than 70/80; cylinder No.5 was 25/80. The mechanic stated he heard air leaking from the exhaust. He staked the valve, but the compression did not change. Mechanics observed 3 ounces of fuel in the gascolator. The carburetor contained a small amount of water; however, the fuel selector valve and main fuel line to the carburetor contained only fuel. The tank vents were clear.