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Help with points on a 66 289

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Old Jun 23, 2005 | 09:40 PM
  #11  
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Default RE: Help with points on a 66 289

Yeah, I ran some emery cloth through the points. They look clean with no wax or anything. The pigtail ground cable looks great. I even used the same emery cloth to buff up the contact point. The coil is hooked up right. One black wire to the dizzy as it clearly states on the coil, and the red snap on wire to the battery. He has a fresh tank full of 91 octane gas, and the see-through filter is brand new and is flooded with gas. It is not a gas issue, but an ignition issue. Driving me nuts.
Old Jun 23, 2005 | 09:47 PM
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Default RE: Help with points on a 66 289

OK so based off what we know, the car was running OK other than an issue about 3K rpms.

Have you tried putting all the stock stuff back in? if so what was the results?

You'd have to go a long way turning the distributor to make it run really poor. does it kick back against the starter when you crank it over?

Let me know if you've got a digital multi meter and/or an analog sweep arm multimeter. I can give you some instructions to test the whole darned thing. That way you can fix all the issues at one time and be done with it.

Scott
Old Jun 23, 2005 | 09:54 PM
  #13  
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All my multi meters are in storage, so I would have to buy one. What brand, etc. do you suggest? I did put all the previous parts back in, and it still does the same thing. Just turns over really fast, and tries to start, but just won't. No, it doesn't kick back.
Old Jun 24, 2005 | 12:51 AM
  #14  
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Default REally long test procedure that covers the whole thing.

Well I'm a spoiled brat so I only use Fluke meters. Man I'm hard pressed to give you a good answer because if you've got good meters in storage, it's tough to spend the kind of money a good meter costs, just to fix one problem. For the amount of stuff I do, the minimum for me is a Fluke 88 (about $300.00). My Grandpa once told me only rich people can afford to buy cheap, the rest of us have to buy the best we can and make it last. That advice has saved me thousands of dollars.

Hmmm.............................................. .....

OK how about two approaches. First the cheap way, and the other the "right" way. This could be rather long so bare with me.

If it spins over quickly, chances are good we aren't lighting off the fire. OK................, First lets see what kind of spark we are getting from the coil. With a screw driver in the end of the coil wire hold it about 1/8" over a bare piece of metal away from the carb. What kind of spark do we have? Good constant solid blue to bright yellow, and we need to hook up the coil wire and do the same test with a spark plug wire. no spark from the coil or light dull yellow and we need to check out the whole primary (12V) side of the ignition electrical as shown below. If we've got good constant spark (doesn't die off after several revolutions) and either no spark or lousy spark from the spark plug wire, and we need a cap and rotor, maybe plug wires. Follow tests with meter as outlined below.

Now we're starting to get serious (but haven't bought a meter yet):
Get your timing pointer at 8 degrees BTDC number one cylinder. Easy to do, just remove the postive to the coil, pull out the number one plug, twist a paper towl or rag up to the size of the spark plug hole and jamb it in (not deeper than the spark plug but has to fit tight). Tap the engine over until the rag "pops" out or you hear the compression blow by the rag. Hand turn the the crank with the ignition switch OFF!!!!, until the pointer is at 8 degrees.
Your ignition rotor needs to be pointed to the number one plug wire on the cap. If it's not your firing order is incorrect. Start with the number one plug wire plugged in to where the rotor is pointed, and correct all teh other plug wires. If all this is correct keep on digging.
You want to turn the distributor until the points barely break contact, then lock it down. That's going to get you close enough that the engine should start and run OK. Hook up the postive wire to the coil, and try starting the car.
If it starts and runs OK, forget the rest of this post and make your friend buy you some really good beer while you finish off adjusting timing on the running engine.

I prefer a timing light for initial setting and a vacuum gauge and driving/starting to get final timing set. The only time I've ever seen a harmonic balancer slip is when the engine was soaked for a long period of time with oil from a worn out timing cover seal, but then I haven't worked on every car ever built either.

Now if we still don't have a running engine, try a jumper wire from the postive battery terminal to the positive coil. Leave the positive wire from the ignition switch on the coil, just pull it up a little. You don't want to do this for more than a few minutes, because the coil is not designed to run off 12V. Try to start the car if it starts and runs remove the jumper wire from the battery post. If it dies we have a problem somewhere between the battery and the coil, and it's time to buy a meter. BTW: if it does start and run the only way to shut it off is to remove this jumper and turn off the ignition key. If it still doesn't start we have an issue on the negative side. You can make a short lead up to replace the one from the coil to the points to see if that wire is broken internally.
Next you can make a cheap test light by using a GE83 bulb and solder a couple of wires on to it. Turn the engine over until the points close. With the ignition key on, place one wire from the bulb on the nut of the contact points and the other on the frame of the distibutor. If the bulb even dimly glows we have a problem with the points. At that point if you really want to be certain take a flash light bulb and make the same test light. Do the same test, again it shouldn't even glow. If you have a large arc between the point tips, or absolutely no spark between the tips, there is either a problem with the condensor or the little ground pigtail that runs from the body of the distributor to the breaker plate. This is kind of a harsh test for a condensor but does work, you can take the condensor out of the distributor hook the wire to the positive of the battery and touch the body to negative. Hold it on for a second or so (takes about 3 miliseconds to charge it). now remove it from the battery and touch the wire to the body. You should get a pretty good spark (not like a coil spark but a small blue flash). If at this point we haven't found the problem, it's time to get a good meter and follow the steps below. Anytime you find a problem and fix it always make sure to repeat the test, and follow the rest of the tests to make sure there are no other problems.

Test 1). First we need to check the battery. Just because the engine turns over doens't mean there is enough voltage to start it.
a). Hook the meter to the postive and negative posts of the battery.
b). remove the positive wire to the coil and crank the engine over.
Test results Greater than 9.5V and we have enough to start the car. Less than 9V and you need to take you battery in for a real test.

Test 1a).
a). Meter set to DC voltage (scale set to 15V or closest to this range on manual meters).
b). disconnect positive wire to distributor. connect positive meter lead to clean bare metal on engine. Connect negative meter lead to negative battery post. Crank engine over while observing meter.
Results. Greater than 0.4V clean negative battery post, terminal and cable lugs. Retest. If still greater than 0.4V replace negative cable.

Test 1b).
a). Meter set to DC voltage (scale set to 15V or closest to this range on manual meters).
b). disconnect positive wire to distributor. connect positive meter lead Positive battery post. Connect negative meter to battery cable lug on starter relay. Crank engine over while observing meter.
Results. Greater than 0.4V clean positive battery post, terminal, all cables and lugs then retest.

Battery & cables good, now it's time to check the ignition. I use the rule of halves in my trouble shooting, Half the system is positive and half the system is negative so we start there. Once we find out which side the problem is on we split that side in half find which half is the problem and split that in half. Etcetera, Etcetera, until we get to the component that has failed. With this in mind lets get to troubleshooting:

NOTE: Do not leave key on with points closed for more than a minute or so. The coil will get very hot and could be damaged. Let coil cool off between tests.

Test 2).
a). Meter set to DC Voltage (closest scale to 15V if your meter is manual).
b). Positive lead on positive battery post, negative lead on positive coil post with wire connected, points closed and key switch on.
Results: meter reads betwen 3.5V and 4.5V Positive side is good, go to test 3. Meter reads more than 4.5V positive side has problems go to Test 4.

Whether or not we found a problem on the postive side we are going to check the negative side. No sense not fixing everything! and there are times that it is the cumulative issues that add up to the overall problem. You don't see one big thing jump out at you. Fix it all!!! Do it once and do it right.

Test 3).
a). Meter set to DC Voltage (Closest scale to 15V if your meter is manual).
b). Positive meter lead on negative coil post, Negative lead on negative battery post. Key switch on points closed
Old Jun 24, 2005 | 11:51 AM
  #15  
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Default RE: Help with points on a 66 289

Thanks Scott. I'm heading out to the barn right now with your 5 pages of instructions. I may not be back for a few days with all this stuff to check. Wish me luck!
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