Chapter 8: Troubleshooting - Indmar 5.7L Vortec Operator's Manual

Your Indmar engine is manufactured under strict quality
control standards. It is tested along with a full spectrum
gas analysis. It is operating at optimum levels before it is
shipped. Indmar engines have the exclusive Indmar
3-year limited warranty.
Difficulties can occur. Use the following problem
diagnosis charts to help pinpoint problems. In most
cases, you will need the assistance of your Indmar deal-
er to correct the cause of the problem.
Poor Gas Mileage
1. Fouled spark plugs
2. Plugged flame arrestor
3. Poor driving habits
4. Closed or partially closed choke (carbureted
engines only)
5. Plugged positive crankcase ventilation system
6. Black smoke at exhaust outlet shows rich gas mixture
7. Excessive boat loads (weight)
8. Damaged or dirty hull
9. High altitude adjustment required
10. Adjustment for temperature extremes required
Indmar Marine Engines
Chapter 8
TROUBLESHOOTING
Hard Cold Start
1. Weak or discharged battery
2. Choke held open (carbureted engines only)
3. Loose coil or ignition wires
4. Engine Flooded
5. Fouled spark plugs
6. Lack of fuel at carburetor (carbureted engines only)
7. Battery cables loose or corroded
8. Loose electrical grounds at engine
9. Ignition switch problems
10. Dirt or water in fuel system
11. Engine needs tune-up
Poor High Speed Performance
1. Fouled spark plugs, incorrect spark plug gap or heat
2. Closed or partially closed choke (carbureted
3. Dirt or water in fuel
4. Lack of fuel in carburetor (carbureted engines only)
5. Restricted exhaust system
6. Plugged flame arrestor
range
engines only)
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