How to Diagnose a No-Start on Your Collectible Car

There are many reasons why your car may not start. With the older cars (before computers), it is a bit easier to diagnose, as you do not need a scanner to diagnose it. For the basics on your collectible or antique car’s no-start problem, read on!

Difficulty: Moderate

Instructions

1. If you have a no-start that just clicks, you will need to check your battery and/or alternator and your starter. You will need a voltmeter to check the battery. Attach the voltmeter to the battery. You should have around 12 volts. If not, hook up a jump box and see if the car will start.

2. If the car starts, check the voltage again. You should be running around 13 volts. If you are, turn on the lights and the heat (or air conditioning, if you have it). If the voltage drops significantly, you most likely have an alternator problem. You may also have an alternator problem if the battery seems to check out ok, but you cannot keep a charge on it.

3. If you try jumping the car, and you are still getting the click, you need to check the starter and the starter relay. Check power to the starter. If you are getting power, the starter is bad. If you are not getting power, chances are, the relay is bad. It is a good possibility that you could have a bad relay and a bad starter.

4. If you have an issue where the engine turns over but does not start, you will need to check to see if you have a problem with fuel or spark (ignition). Most of the older cars are carbureted. You should be able to open the butterfly and see if gas is pouring into the carb when you move the throttle. You can also check the bowls by removing the bowl screw and rocking the car a bit to see if gas comes out of the bowl screw hole.

5. If you have no fuel and you have a mechanical pump, you most likely have a fuel pump problem. If you have an electrical pump, you could have a fuel pump relay problem, a fuel pump problem or a wiring problem.

6. It is much easier to check spark plugs. Simply remove a plug wire from the spark plug. Stick another plug into the wire, and lay it against the metal on one of the accessory brackets. Have someone crank the car over and watch to see if you see a spark. If you do, the issue is most likely not with spark.

7. If you have a spark problem, you could have a problem with the distributor, coil or wiring. There is also a chance that you could have a problem with your ignition switch.

8. There are other no-start problems, but unless you are racing or otherwise straining your car and/or not doing the required maintenance, chances are slim that you’ll run into them. They are things such as a broken or very loose timing chain, a broken piston or rod (more like to make a banging noise, but if the rod is stuck in the side of the block, you may get a “clunk” noise when trying to start the car), broken valves or broken valve springs.

Tips & Warnings

• If you end up changing your alternator, be sure to disconnect the positive battery cable.
• If you disconnect the negative side, and it grounds against some metal, the result is the same as if you never disconnected the battery.

[yinbengui]

on 10/4/2008 Thanks
http://mmkt.co.cc

[Melessa]

on 8/25/2008 Thanks

[MacDonald]

on 5/8/2008 Very good step by step advice. In my case it was the fuel pump. :(