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Troubleshooting Guides - Post Breakdown Checklist

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Troubleshooting Guides - Post Breakdown Checklist

Postby TechTeamMod » Sun 7th Sep 2008, 07:10pm

Post Breakdown Checklist

Print this out and keep it in the car along with your emergency tool kit. It might save you a long walk! If your car cough's splutters then dies it's probably a fuel problem, if the engine just dies (and all the lights come on while you're driving) then it?s probably an electrical problem.

Electrical Checks
If the car won?t turn over and the ignition lights don't light up, check the battery terminals are tight and that the earth strap is attached to the boot floor.
If these are in place, chances are your battery is flat. Try jump leads or a bump start. Also check your fan belt is still in place and correctly tensioned as this may be the reason that your battery has gone flat.

If the ignition lights are on but the engine doesn't turn over, turn the key and listen for a clicking noise under the bonnet on the driver's side. This is the solenoid switch. If there is no clicking noise, check the drivers side of the engine. You?ll see the main power wire (thick one) and next to it should be a thinner one. This?ll either be on the starter motor or on the drivers side inner wing (in the engine bay). Wiggle this wire to check its connected.

If this doesn't help possibly the starter motor is faulty. If so, the car should still bump start.

If you hear a clicking sound then check the thick wire is attached tightly. Also check the earth strap next to the engine stabiliser is bolted on and not broken, loose or corroded.

If this is all in order try giving the starter a firm hit with a pole or jack handle then try starting again. This is often useful for freeing a stuck starter.

If the car turns over but doesn't fire at all you need to check the ignition system. Pull the king lead (centre wire) off the distributor (with ignition off) then sit it next to a head stud (within a couple of millimetres) and turn over the engine. It's possible to do this with the window open and see the top of the engine. You should see spark jumping from the connector on the lead to the cylinder head stud. Even better, if you have a spare spark plug you can connect it to the king lead and check that it sparks correctly.

If there is no spark, take off distributor cap and check all wires are in place, that the points open and close when engine turned over (assuming you have a conventional non-electronic ignition). You can turn the engine over by hand by using the fan belt or by rolling the car forwards with it in second gear and the handbrake off).

If the points stay open or don't open at all then re-set them. The gap should be 0.35-0.40mm which incidentally is roughly the thickness of a bit of card from a matchbox or the card on the back of a blister pack of fuses. Also check that the rotor arm is clean on the top and tip of the arm. This can be cleaned by rubbing it on the sidewall of the tyre.

Also check that there is a carbon brush (like a pencil lead) in the middle of the cap and that there is no sign of moisture in cap (if there is then dry it with a rag, hanky, McDonalds napkin etc).

Also check the wires (thin ones) coming off the distributor are all intact.

If there is a spark, replace the king lead then take off one of the spark plug wires at the spark plug end. If you have a spare spark plug you can connect the removed lead to the spare plug. Otherwise you will have to improvise a spark plug using a nail, metal screwdriver or similar. Place the spark plug on the cylinder head and turn over engine looking for a spark. If you're using an improvised spark plug then make sure the end of the piece of metal is a couple of millimetres from the cylinder block. If there's no spark then re-check the distributor cap, and make sure that the end of lead is pushed right into cap and is copper colour, not black. If all looks OK, spraying with WD40 will banish any water.

Fuel system checks
Is there any petrol in the tank? Are you sure? Even though the gauge might say there is fuel, it could be reading incorrectly. Take off the filler cap. If you hear a hissing of air when you do this your breather pipe could be blocked causing a vacuum. Drive home and take off cap when ever car cuts out! Shake the car and listen, or shine a torch in, but whatever you do, don?t use a match to see!!!

If you have an inline fuel filter check it contains fuel. If it's before the fuel pump (how can you see it?) and empty, the fuel isn't getting through.

If it?s after the pump, it could be blocked or your pump might have packed up. Take the fuel line off the carb and turn the engine over. Fuel should pulse out pipe, so be careful that you don't spray it everqywhere.

If no fuel comes through when you turn the engine over, try taking off petrol cap and blowing as hard as you can down the fuel line until you hear it bubbling in the tank. If no bubbling then fuel line blockage is the probable cause.

If fuel pulses out then could be blockage in carb. Try spraying a little WD40 into the throat of the carb with the air box removed, then try to start car. WD40 will fuel your car enough to start.

If it fires up you know your carburettor is your problem. Try starting it, with the throttle wide open and a rag jammed tightly over the carb throat until the engine cuts out or really slows. This should suck any blockages out of the carb jet. Bump starting it with the choke fully out (and rag jammed in the carb neck) can help with this also.

If it still won't start, it's probably time to call it a day. Call the breakdown services or your favourite local garage for help.
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