ENGINE — 2UZ-FE ENGINE 39 VALVE MECHANISM 1. General Each cylinder has 2 intake valves and 2 exhaust valves. Intake and exhaust efficiency is increased by means of the larger total port areas. The valves are directly opened and closed by 4 camshafts. The intake camshafts are driven by a timing belt, while the exhaust camshafts are driven through gears on the intake camshafts. Exhaust Camshafts Intake Camshafts Timing Belt 156EG38 2. Camshafts The camshafts are made of cast iron alloy. The cam nose has been chill treated to increase its abrasion resistance. The exhaust camshafts are driven by gears on the intake camshafts.
The scissors gear mechanism is used on the exhaust camshaft to control backlash and suppress gear noise. Intake Camshafts Timing Pully Exhaust Camshafts 156EG39 Scissors Gear Mechanism