Have fuel, cranks, no start diagnosis-----diagnosis

emmd61

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Hi.

Can you place a spark tester between ignition coil and distributor to see if problem is upstream from distributor? Did not seem to get a spark at plugs.

Thanks
 
Hi.

Can you place a spark tester between ignition coil and distributor to see if problem is upstream from distributor? Did not seem to get a spark at plugs.

Thanks

First use a volt meter to see if there is power coming out of the ballast resistor. If you have power there, check the point gap and the point resistance, a car that sits often has corroded points. Check the distributor cap and rotor for corrosion also. Yes, you can use a spark tester to see of the coil is firing, usually simpler to pull the coil wire from the distributor and place it about 1/4" from a good ground, if you have spark when cranking, then the problem is probably with the distributor cap or rotor. If there is no spark, test the coil by removing the lead to the distributor from the negative side of the coil, take some jumper clips and touch the negative lead quickly to the block and remove it, the coil should fire the coil wire when you do this with the key on. If there is power to the coil and it does not fire, the coil is bad. Note that on the start cycle there is a different circuit with higher voltage that is wired seperately from the run position, both circuits need to have power, one with the key in the start position, the other with the key in the run position. Start circuit will have battery voltage, the run circuit will have at least 6.8 volts.

Dave
 
I use a Induction pen from champion. It will read the coil spark and any of the plug wires.
 
Points? Electronic ignition? What is on the car?
 
Standard fuel starts to go bad at 30 days, almost unburnable at 90 days, tho I have started fuel injected cars after 90 days
 
If the fuel has been sitting for a long time don't run the engine with it. Drain the tank completely and flush the gas line with new fuel. I did this and the engine ran poorly. After shutting it off and trying again after the engine cooled, all the intake pushrods were bent. This was due to the old gas turning into glue in the intake passages with engine heat. Had to take the heads down to a machine shop and have the valves pounded out. An expensive mistake on a newly rebuilt engine. The machinist said he has only seen this on cars where the owner ran old gas through the engine. Don't make this mistake.
 
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