QuestionQUESTION: I had to start a new question bc I had no further follow up questions permitted. The spark occurred at the same time as my thumb was blown off the hole. I tried this test with all four spark plugs with the same results. I don't have a garage, but the car was in heavy shade and the sparks seemed tiny and white/orange instead of fat and blue. I shot starter spray into the intake also without success. A friend suggested I pour some gas into a spark plug hole and try to start it then. Not a pop from that either.
thanks again for your help
ANSWER: Hmmm! I didn't know they had a limit on follow up questions. No problem, just remind me what we were talking about like you did so I can keep up.
The starter fluid and gas test you ran were good tests, showing the weak spark seems to be the problem. Remove the distributor cap and see if you can ID what kind of ignition you have. Many of these cars have had their ignition systems changed as the original Lucas electronic system was not much good. Some even went back to pointed ignition systems.
Also, you said you were concerned about the battery. Why? Did you put it on a charger? Do you have a volt meter? If not you can get a inexpensive one at Radio Shack or some place like that.
Check battery voltage then have someone try to start it while you check battery voltage. Then check from the + side of the coil to the engine block with the key on and then while trying to start it. Battery voltage should be 12.5+ and should not drop below 10 volts while cranking. Let me know what the readings are.
Another good test is to connect the (-) black test lead of the voltmeter to the negative post of the battery (not the cable end) and put the + positive test lead on the engine block and have someone try to start it. You should not see more then .5 volt. This is a "voltage drop test" of the ground strap and battery to body ground.
There are some rough tests of the coil out put but you need plastic pliers to run it. Normally a Lucas coil will produce from 25,000 volts to about 35,000 volts on a scope and I found that a coil as low as 25K will still jump a spark about 1/4 inch and a 35K spark will jump about 3/8 inch. With a weak spark you may have trouble jumping 1/4 inch.
Do this before we condemn the ignition system. If the spark plugs are clean (center electrode insulator white) then take a thin file (finger nail file works well) and file the center electrode and negative electrode. I found that a used plug could drop the required voltage to jump the gap by 5,000 volts under pressure just by filing the electrodes. Set the plug gap at .025".
Even though a good coil will build to a higher voltage with a wide gap, when you have a weak spark for what ever reason it fails to jump under compression.
Clean the plugs or get new ones if they are black and dirty as a weak spark will not jump the gap when under compression. That is part of the reason new cars have very high energy coils. They also don't want to jump the gap under lean fuel conditions like new cars have. The starter fluid test was a good test that there was no spark under compression because it ignites with even the weakest spark. When you have a weak spark out in the air, it will not spark at all under pressure of compression.
let me know,
Howard
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QUESTION: the distributor is an ignitor by perlux. I charged the battery up and then attempted the tests. The battery reads 12 sitting, and drops below 5 when starting. Measuring from the + to block is 12 and when starting, below 5. My tester only has three lights, 12.5, 12, and 5. So it seems that the battery is not in great shape.
I bought new plugs, but noticed the plugs from cylinders 3 and 4 were very oily, while 1 and 2 were brown and dry. I checked the oil and it was overfilled, so I drained it down to the high mark. I didn't want to put in the new plugs and possibly foul them up until I heard what you thought about the oily plugs and battery.
AnswerWill, You need to get a volt meter. If your light tester is correct you have a large problem because you must not drop below 9 volts on a starter test as the ignition system and coil can not operate at down around 5 volts (if your light tester is correct) There are other things that can cause the voltage to drop when the starter is engaged like a "Dragging Starter".
Perlux is an aftermarket ignition system and was a normal replacement when the Lucas/Opus system failed and they always did. You can't tell if the perlux igniter has failed because IF you have such low voltage even a good one will not fire plugs under compression.
Oil on the plugs may of may not mean anything but now you MUST run a compression test. compression gauges are not expensive and I have even seen them at Wall Mart. Be sure to hold the throttle open when testing and be sure the engine spines over at least 4 of 5 revolutions on each cylinder test.
The readings should be from about 125 to 180 PSI and only a small difference between cylinders.
You need to get the tools to correctly test or you will be buying parts that are not bad. Even the battery still can't be condemned until you charge it up first and take it to any auto parts store. They have a "Load Tester" to test a battery and will usually test your battery for free.
You don't need a professional grade compression gauge or volt meter so you can get them at Wall Mart and Radio Shack or even at a Harbor Freight if you have one close.
Howard
