1. Connect one end of the manometer to the engine oil dipstick hole. The other end of the manometer is vented to atmosphere.
2. Install the air cleaner.
3. Start the engine and observe the manometer reading. It should read one inch of water pressure at idle to approximately 3 to 4 inches of water vacuum at full load. Add the amount that the manometer column travels up, to amount column travels down to obtain total psi/vacuum. An example of a manometer reading is as follows: One-half inch above zero plus one-half inch below zero equals one inch vacuum reading (1/2” + 1/2” = 1”) (figure 5).
