Chevrolet LUV Pick-up Truck Repair & Service Manual 1972-1982 by Haynes

ENGINE MISFIRES

10. If the engine misfires regularly, run it at a fast idling speed. Pull off each of the plug caps in turn and listen to the note of the engine.
    
    Hold the plug cap in a dry cloth or with a rubber glove as additional protection against a shock from the HT supply.



11. No difference in engine running will be noticed when the lead from the defective circuit is removed.
    
    Removing the lead from one of the good cylinders will accentuate the misfire.



12. Remove the plug lead from the end of the defective plug and hold it about 1/4 inch away from the block.
    
    Restart the engine. If the sparking is fairly strong and regular the fault must lie in the spark plug.



13. The plug may be loose, the insulation may be cracked, or the points may have burnt away giving too wide a gap for the spark to jump.
    
    Worse still one of the points may have broken off. Either replace the plug, or clean it, reset the gap, and then test it.



14. If there is no spark at the end of the plug lead, or if it is weak and intermittent, check the ignition lead from the distributor to the plug.
    
    If the insulation is cracked or deteriorated, replace the lead. Check the connections at the distributor cap.



15. If there is still no spark, examine the distributor cap carefully for tracking. This can be recognized by a wry thin black line running between two or more electrodes, or between an electrode and some other part of the distributor.
    
    These lines are paths which now conduct electricity across the cap thus letting it run to ground. The only answer is a new distributor cap.

UNIVERSAL JOINTS | REPLACEMENT
(Refer to illustrations 5.2a, 5.2b, 5.3 and 5.8)

1. Remove the driveshaft (see Section 3).



2. Clean away all dirt from the ends of the bearings on the yokes so the snap-rings can be removed with a pair of needle-nose pliers or a screwdriver (see illustrations).



3. Place a piece of pipe or a large socket with the same inside diameter over one end of the bearing caps. Position a socket of slightly smaller diameter than the cap on the opposite bearing caps.
   
   Position a socket of slightly smaller diameter than the cap on the opposite bearing cap (see illustration) and use the vise or press to force the cap out (inside the pipe or large socket, stopping just before it comes completely out of the yoke.
   
   Use the vise or large pliers to work the cap the rest of the way out.



4. Transfer the sockets to the other side and press the opposite bearing cap out in the same manner.



5. Pack the new U-joint bearings with grease. Ordinarily, specific instructions for lubrication will be included with the U-joint servicing kit and should be followed carefully.



6. Position the spider into the bearing cap, then partially install the other cap. Align the spider and press the bearing caps into position, being careful not to damage the dust seals.



7. Install the snap-rings. If the snap-rings are difficult to seat, press the bearing cap in a little more with the vise and socket.



8. If the joint is stiff after assembly, strike the driveshaft yoke sharply with a hammer (see illustration). This will spring the yoke ears slightly and free-up the joint.



9. Install the grease fitting and fill the joint with grease. Be careful not to overfill the joint, as this could blow out the grease seals.



10. Install the driveshaft, tightening the companion flange bolts to the torque listed in this Chapter's Specifications.

• Introduction: Vehicle identification numbers; Buying parts; Maintenance techniques, and more.
• Tune-up and routine maintenance
• Engine and overhaul procedures
• Cooling, heating and air-conditioning systems
• Fuel and exhaust systems
• Engine electrical systems
• Emissions control systems
• Transmission
• Brakes
• Suspension and steering systems
• Body
• Chassis electrical system
• Wiring diagrams