If you have a Corvette that refuses to crank, let alone start, you have several troubleshooting options for modern starter systems. Heat or compression is usually the culprit in problems with the starter turning over. Diagnosing starter problems is simple, requires little time and can be done in your own garage.
Test your battery to first rule out a weak or dead battery. Use the most sensitive setting on the multimeter in DC volt mode: 1 to 2 amps constantly would indicate a drain. To isolate a drain, hook up the negative batter cable to an amp clamp. Remove each fuse until you isolate the drain. Make sure the terminal is not corroded and there are no bad grounds. This is probably where the engine or chassis meets the ground strap. If the starter is working sometimes, but making a grinding noise, inspect the armature shaft. A fractured armature shaft can cause weak engagement with the ring gear.
If the starter does nothing yet the headlights remain bright when turned on, an open circuit may be the cause. Hook up a booster cable from the battery directly to the terminal. If the starter does not turn over, check the neutral safety switch component. If the starter works fine after you by-pass the switch, then you have found the cause.
Turn on the switch and listen for solenoid clicking sounds. The solenoid contacts might be burned, which would prevent the solenoid from supplying a heavy current to the starter. This problem can be resolved by simply replacing the solenoid.
If cranking is sluggish or the starter is slow, the load may be too heavy. Check the mechanical advance to make sure it's not stuck. Reduce the advance if possible.
The engine may be "hydrauliced" if the starter is making a lot of noise or the engine completely refuses to turn over. The most likely cause is a leaking head gasket, although a broken block or stuck float could be possible causes. Remove every single spark plug and see if the engine turns. If it turns over normally, you will be able to determine what the problem is as liquids cannot compress.
If you are required to replace the starter take it to the automotive store. Most stores offer credit for old starters toward a brand new one. Consult your car manual or a professional technician to make sure you buy the correct replacement starter.
