Chevrolet 70 1969 Series, Shop Manual

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G ASO LINE ENGINES 6A-18
HARD STARTING (CONT.)
S Y M P T O M D - IGNITION T R O U B L E S (Cont'd.)
POSSIBLE CAUSES R E M E D Y
6. Defective ignition coil or condenser. 6. Test coil and condenser; replace if necessary.
7. Cracked distributor cap. 7. Install new cap.
LACK OF
S Y M P T O M A - P O O R COM PRESSION
POSSIBLE CAUSES
1. Incorrect valve lash.
2. Leaky valves.
3. Valves or lifters sticking.
4. Weak or broken valve springs.
5. Valve timing incorrect.
6. Blown cylinder head gasket.
7. Broken or stuck piston rings.
8. Worn pistons, ring, and/or cylinder bores.
S Y M P T O M B - IGNITION S Y S T E M M A L F U N C T IO N
POSSIBLE CAUSES
1. Ignition out of time.
2. Defective spark plugs.
3. Distributor points worn or out of adjustment.
S Y M P T O M C - L A C K O F F U E L
POSSIBLE CAUSES
1. Dirt or water in carburetor.
2. Gas lines partly clogged.
3. Dirt in gas tank.
4. Air leaks in gas line.
5. Fuel pump not functioning properly.
6. Governor malfunction.
S Y M P T O M D - EX C ESS IV E F U E L (FLOO D IN G )
POSSIBLE CAUSES
1. Choke not fully open.
2. Air cleaner restricted.
3. Carburetor float valve not seating.
4. Rich mixture at idle speed.
POWER
R E M E D Y
1. Adjust to correct clearance.
2. Remove cylinder head and grind valves.
3. Free up or replace.
4. Replace defective springs.
5.
Correct the valve timing.
6. Replace gasket.
7.
Free up or replace piston rings.
8. Overhaul engine.
R E M E D Y
1. Set ignition timing.
2. Clean or replace sparkplugs.
3. Clean and adjust points or replace.
R E M E D Y
1. Clean carburetor.
2. Clean gas lines.
3. Clean gas tank.
4. Tighten and check gas lines.
5.
Replace or repair fuel pump.
6. Repair or replace governor.
R E M E D Y
1. Check choke and adjust control.
2. Service air cleaner.
3. Clean float valve and set float level.
4. Adjust carburetor idle mixture.
CHEVROLET SERIES 70-80 HEAVY DUTY TRUCK SHOP MANUAL