OK. I got in my truck and tried to start it and the starter just hit the flywheel and didn't turn over. It did that twice, on third time there was no power at switches or gauges. My hood and dome lights were still on. I tried jumping starting it and still nothing. My friend was checking voltage at the junction block and now my truck will turn over but wont crank up. Fuel pump is working and the starter is fine. I'm thinking its some wire to the switch or the coil. Its a 1988 Chevy truck with a 350.
How do you know the starter is good?
Put a test light on the purple wire on the starter solenoid and try to start the engine, when you turn the key to the start position the test light should light up. This checks the ignition switch circuit. If it doesn't light when the key is turned to the start position then check the wiring to the switch and the switch itself. Repair or replace any faults you find.
Check the grounds from the battery to the engine and also the body grounds for any loose or corroded connections.
Make sure that the battery cables connections are clean of any corrosion.
Check the voltage drop on each wire to be sure it has a good connection. Just because it looks good doesn't mean it is. That goes for all connections.
If the starter does turn the engine check the cranking amps. If the starter draws more than 250 amps, look into a faulty starter.
Try these suggestions and get back to me with your results.
If needed I will look into this further. If you can supply me with more detailed information. The more information you can give me the more answers I can give you.