SECTION AIR INTAKE SYSTEM

Size: px

Start display at page:

Download "SECTION AIR INTAKE SYSTEM"

Alvin Johnston
5 years ago
Views:

1 / AL05 SECTION AIR INTAKE Air for the engine is taken in through a grille located on the upper-rear, left-hand side of the vehicle. See Figure 1. Air passes through a chamber, reaches the air cleaner mounted near the radiator, then passes through the air cleaner and into the turbocharger of the engine. AIR CLEANER An air cleaner is used to remove dust and dirt before the air reaches the diesel engine turbocharger. It is a dry type air cleaner, and the filter element can be easily removed for cleaning or replacement through the access grille located on the rear left corner of the bus. An optional air intake restriction indicator (Filter Minder) may be installed on the engine air intake in order to inform the service personnel when the air cleaner is restricted and needs replacement. For more details on the restriction indicator, see sub-section A: AIR INTAKE RESTRICTION INDICATOR, at the end of this section. STREET SIDE AIR CLEANER MAINTENANCE MAINTENANCE INTERVALS An appropriate inspection will extend the life span of the engine and air cleaner. It is recommended that the air intake system be checked regularly. The recommended inspection interval is every time the engine oil is changed. It is not necessary to disassemble the air cleaner for inspection. The complete air intake system should be checked in the following sequence: 1. Air cleaner casing (cracks, disassembled, loose nuts or bolts) 2. Restriction indicator (loose, missing) (optional) 3. Drain valve (missing, worn-out, loose, turned the wrong way) 4. Clips on the air intake system (loose, broken) 5. Air intake system (broken or missing flanges, holes in the system). 6. Perform a stall test and refer to the Cummins engine manual for normal rpm values during the test. The engine should reach the specified values indicated in the Cummins engine manual. Replacing, repairing, or correcting any faulty situation will increase the service life of the engine and air cleaner. Figure 1 - Engine Air Intake (Typical)

2 2007AL05 2 / SHORT LIFE SPAN If the service life of the filter element is too short, check for the following: 1. Leaks in the air intake system. A leak can cause a short life span. If a restriction indicator is installed on the air intake system (see sub-section A: AIR INTAKE RESTRICTION INDICATOR, at the end of this section), also check for the following: 2. Restriction indicator improperly installed. It should be turned downwards and its lugs parallel to the airflow coming from the engine fan. It should be checked to ensure that it is neither obstructed nor turned the wrong way. 3. Wrong maintenance indicator. Use only genuine Nova Bus maintenance parts. The indicator is calibrated for the desired final pressure drop. Filter should NOT be cleaned and re-used. REPLACING AIR CLEANERS Do not replace the filter element unless the yellow ring of the restriction indicator (optional) is visible or when the obstruction has reached 22 in. H 2 O (0.8 psi) on the air restriction indicator. 1. Stop the engine. Remove the cover plate of the air cleaner. See Figure Carefully move the filter element up and down and from side to side or turn it so as to release it from the seal. See Figures 4 and Remove the filter element by making sure not to touch the casing walls. See Figure 8. Check the accuracy of the restriction indicator using a water pressure gauge or an indicator at the air intake casing of the blower assembly; the fitting may be clogged with dirt. WARNING: Carefully avoid shaking dust from the filter element. Any loose dust must be removed from the air cleaner body with a wet cloth before installing a clean element. DUST ESCAPING FROM THE AIR FILTER ELEMENT Dust escaping from the air cleaner may cause the engine to wear out rapidly. Make sure that all fittings between the air cleaner and the engine are tightened and sealed. If all fittings are tight, check for the following: 1. Make sure that the filter element seals are not damaged. 2. Check the filter element to ensure that there are no tears in the folds (holes, cracks or tears can be detected where there is evidence of dust streaks on the clean side of the element. Also, hold a light bulb inside the element; light will shine through any holes). These problems would be evidence of filter element failure, and it should be replaced. 3. If installed, check the restriction indicator to detect leaks. 4. Look for structural failure. Any damaged parts must be replaced. 4. Clean the inside surface of the casing. This will prevent dust from hindering the efficiency of the filter element. See Figures 6 and 7. Inspect the old filter element to detect any foreign matter on the sealed surface that might tamper with the efficiency of the new filter element. Apply a maximum torque of 30 lb-in. (3.4 N m) on the clamp at the filter outlet. A higher torque could damage the filter s casing. Dust going through the air filter element can often be detected by looking for streaks of dust in the air duct. COVER PLATE Figure 3 - Air Cleaner Casing

09-500.295/ 3 2007AL05 INPUT SEAL OUTPUT Figure 4 - Access to Filter Element 5. Inspect the new filter element. Check the surface of the seal inside the air cleaner.

The air intake to the engine may break or collapse a wet filter element. 6. Check the element to make sure that all piping and fittings are of the proper size and are not clogged. 7.

3 / AL05 INPUT SEAL OUTPUT Figure 4 - Access to Filter Element 5. Inspect the new filter element. Check the surface of the seal inside the air cleaner. It should be smooth, flat, and clean. Do not install a damaged filter element. Under no circumstance should a wet element be installed. The air intake to the engine may break or collapse a wet filter element. 6. Check the element to make sure that all piping and fittings are of the proper size and are not clogged. 7. Install the new element to evenly distribute the pressure at the bottom flange seal. See Figure Check the seal of the access cover and tighten the cover nuts. 9. If installed, reset the restriction indicator by pushing the button located on its lower part. 10. Close the access doors. Figure 5 - Direction of Rotation Figure 6 - Cleaning of Casing Figure 8 - Remove Filter YES NO YES Figure 7 - Cleaning the Casing Cover Figure 9 - Pressure Distribution

4 2007AL05 4 / BLANK PAGE

SECTION 09-500.295 AIR RESTRICTION INDICATOR 09-500.295/ 5 2007AL05 DESCRIPTION See Figures A1 and A2.

5 SECTION AIR RESTRICTION INDICATOR / AL05 DESCRIPTION See Figures A1 and A2. The purpose of this optional device is to warn when the engine air cleaner is restricted and requires replacement. The indicator is designed to prevent any engine damage that could result from a clogged air filter. When the air filter obstructs air circulation, the indicator shows a yellow ring through the transparent part of its casing. Temporary conditions such as snow or inlet screen clogging can cause a high reading. Pushing the bottom of the gauge will reset the filter gauge. If the reading is still high, (0.8 psi/22in. H 2 O) it indicates that the air cleaner should be changed. Over servicing should be avoided, because this increases the risk for gauge and seal damage. After the maintenance, described further in this section, reset the indicator. This will return the reading to zero. INSTALLATION 1. Remove the existing air cleaner gauge from the air cleaner tap. 2. Remove the air cleaner tap fitting and replace with a new fitting. - Pipe thread sealant should be used on metal fittings. Do not use sealant on the FILTER MINDER. 3. Install the FILTER MINDER gauge to the fitting. Do not over-tighten. Finger tight is sufficient. The FILTER MINDER is now ready to monitor the air cleaner system. The gauge gives a progressive indication of air filter plugging which allows the entire air filter capacity to be used. Actual filter life will vary, depending on operating conditions. STREET SIDE FILTER MINDER Figure A1 - Restriction Indicator (Filter Minder) Figure A2 - Filter Minder Installation (Typical)

6 2007AL05 6 / High restriction No restriction TROUBLESHOOTING GUIDE PROBLEM CAUSE SOLUTION a. Filter is blocked b. Air intake duct is blocked c. External vent is blocked a. Gauge is defective b. Loose clamps c. Improperly sealed filter d. Blocked fitting on gauge a. Replace filter b. Verify and clean duct c. Verify and clear vent a. Replace gauge b. Verify and tighten if necessary c. Verify and replace if damaged d. Remove and clear blockage, or replace if necessary Table 1 - Troubleshooting Guide

FBC CODES AND TRANSLATIONS TRANSLATION

FBC CODES AND TRANSLATIONS TRANSLATION FBC CODES AND TRANSLATIONS CODE TRANSLATION 500 air cleaning system checked 501 air cleaner housing found cracked 502 repaired cracked air cleaner housing 503 renewed air cleaner housing 504 air intake