Exhaust Gas Recirculation: Service and Repair
Every 12,000 miles or 12 months, the complete EGR system should be inspected and tested. To assure proper operation of this system all passages and moving parts must operate properly free of deposits. Hoses and connections must be free from leaks.
On vehicles equipped with floor jet exhaust gas system, every 12,000 miles of operation inspect the floor jets for deposit buildup. With engine off and carburetor air cleaner removed. hold choke and throttle valves open. Using a suitable light inspect the floor jets visually through the carburetor. If there is an open path through the orifice the jets are satisfactory. If a jet is plugged, remove jet, clean and reinstall.
NOTE: Floor jet is non-magnetic, stainless steel material. Caution should be taken so that jets will not fall into intake manifold ports during removal and installation.
Fig.29 EGR Control Valve:
The EGR valve should be inspected for deposits with particular attention to the poppet and seat area. If deposits exceed a thin film condition, the EGR valve should be cleaned. If wear of the stem or other moving components is noted, the valve should be replaced.
NOTE: Extreme care should be exercised during the cleaning operation to prevent spilling of solvent on the valve diaphragm, as this will cause diaphragm failure. Do not push on diaphragm to operate valve, use vacuum source only.