This instruction show you guide on how to test pressure for Scania C,K series truck EGR system.
Note:Sulphuric acid can be formed in the pipe downstream of the EGR cooler. Remember to use safety equipment!
1.Remove the inlet pipe from the intake of the turbocharger.
2.Clean the flange of the turbocharger inlet and the inside of the rubber hose on 99 620 Pressure cap.
3.Fit 99 620 Pressure cap to the turbocharger intake. Tighten the hose clamp.
4.Turn the flywheel using 99 309 Turning tool in the direction of engine rotation until the “TDC-Down” marking is visible in the lower inspection hatch.
5.Connect 99 557 Pressurisation tool to 99 620 Pressure cap. Make sure that the valve (1) is unscrewed anti-clockwise.
6.Connect SDP3 and carry out a check under SDP3 > Checks and adjustments > Functions > Check > Powertrain > Emission control > EGR system > EGR circuit leak testing.
7.Pressurise the system with 1.30 bar absolute pressure.
8.Close the valve (2) and read the air pressure in SDP3.
A pressure drop of 0.01 bar a second is acceptable. If the change is greater than 0.01 bar a second, there may be a leakage.
If there is leakage, check:
- that the EGR valve closes and seals properly.
- that no external air leaks can be heard between connections and hoses, charge air cooler or inlet pipe.
- use soapy water or leak detection spray to visually check for air leaks.
Check the inlet side and charge air cooler
Remove the EGR pipe which connects to the inlet pipe. Plug the connection and pressure test the system according to the method above.
- If leakage is detected. Separate the pipes downstream of the charge air cooler.
- If the pressure drop is more than 0.01 bar a second, even with the EGR system disconnected, continue troubleshooting to check for any other faults.
Check the EGR valve
Disassemble the joint upstream of the EGR damper and plug the pipe. Pressure test the system according to the method above. If the system is sealed with the plugged pipe, the EGR valve is leaking and must be cleaned or renewed.
If the fault is rectified:
Refit all components. Pressure test the system according to the method above. Use SDP3 to delete fault codes which may have occurred while carrying out the work.