Vacuum test engine

1. Vacuum test provides information about the state of the engine: Wear of piston rings and cylinder walls, head gasket or intake manifold air leak in the intake tract restriction in the exhaust tract, the state of the valves and springs, violation of ignition or valve timing problems with the ignition system. 2. Manometer readings during the vacuum test is easy and quite unambiguously interpreted. 3. For the analysis useful as a means manometer readings, and speed of his hands. 4. Gauge directly connected to the inlet of the intake manifold. Gauge readings are as follows: 5.Pri this make sure that all the vacuum hoses were connected to the respective nipples intake manifold to get reliable test results. 6. Before you start check warm the engine up to normal operating temperature. Place wedges under the wheels and then the brakes. Moving the selector to Park, need to start the engine and leave it at idle. Warning: Before starting the engine make sure not to crack the fan blades, the engine is running, do not stand in front of the car and next to the fan. a) Low values ??indicate a leak of air through the intake manifold gaskets, carburetor or throttle body, vacuum hoses, ignition, or the latest violation of the valve timing, check the installation of strobe lighting to eliminate possible problems. Perform test as described in this chapter, before removing the cover to check the timing chain phases. b) If the vacuum at 10 ... 30 kPa (70 ... 200 mm of mercury column) below the norm, and the indications are unstable, the problem may be faulty injector or air leak in one cylinder (strip header). c) If the shooter sometimes falls down (50 ... 100 mm. mercury column) for general stable readings, likely to flow through leaks landing valve in the saddle. Check the compression will help clarify the diagnosis. d) The spontaneous incidence direction can be caused by hovering valve or omission in the ignition. Compression check will help clarify the diagnosis. e) Rapid jumps arrows within 100 mm of mercury column, coupled with a smoky exhaust point to guide wear sleeves. Leak Check will help eliminate the diagnosis. If the needle gauge starts to twitch with increasing engine speed, check the leak in the intake manifold gasket and cylinder heads, repair valve springs, seals, valve / seat, misfiring. e) Small (about 25 mm of mercury column) variations arrows are significant, conduct a test compression, leak checks to determine the faulty cylinder (burnt piston, a broken piston ring or punched strip. g) If the shooter is walking smoothly on a scale, check the cleanliness of the ventilation system channels Carter, of the fuel mix or leak in the intake manifold or throttle body. h) dramatically unwind the engine to about 2500 rpm and relieve gas. The arrow should fall to near zero, climb to 120 ... 150 mm. column of mercury above indications for the idle and return to them. If the vacuum falls slowly and does not reach the maximum when you reset the gas probably worn piston rings. If the vacuum falls slowly, perhaps clamped pipe intake system (muffler clogged with soot or catalyst). To verify this, remove a suspicious section of the exhaust system and repeat the test.