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20 ohm scale means that your reading is somewhere between 0 and 20 ohms. 1.6 ohms sounds normal for a coil using an external ballast resistor. 2000 ohm scale means your reading is between 0 and 2000 ohms, but on that scale you wouldn't have a decimal point unless you have at least 6 digits on the meter. So I assume that you're seeing 439 ohms. If you have lots of digits, that might really be 4.39 ohms. Either of these is much too low in any case. Should be several thousand ohms.

If you mistyped and are on the 20000 ohm (20 K ohm) scale, then 4.39 is reasonable and means 4.39K. "K" just means 1000 ohms, so this is 4390 ohms which is OK.

Unfortunately, resistance readings don't entirely confirm that a coil is OK, since it could be fine at the meter's low voltage but still arc at high voltage. Best test is the ol' pull-a-hood-and-look-for-the-spark test.
 
By the way, don't assume that something new is automatically OK. Bad new parts exist. And, any reliability engineer will tell you that new parts are just as likely to fail as old, worn-out ones. We call this "infant mortality" failure. Any high-reliability device, like for space or medical use, is "burned in" by operating it for many hours to get past this effect.

So, check the diaphragm. Not only unsplit, but be sure it's in right, nothing pinched, all that stuff.

Also, make sure you don't see raw gas in the intake, indicating a float valve stuck open, or anything else strange. I think you said you have an indication of super-rich running, so these things should be suspected. Maybe at this point you should clean the plugs, too, since they might be so fouled it won't run right even if you fix the problem.

I once was told that, when your car dies, check for fuel at the carbs, spark at the plugs, and if you have both, get in, start the sucker, and drive away. OK, that's a bit of an oversimplification, but it makes the point.
 
thanks Steve - especially for the oms piece - I suspect you are right about the scale. Just took out a plug and cranked the motor - I think weak spark may be the culprit. It is sparking - however, it is a yellow spark and I seem to recall a bluer spark when I was trying to start the car a few months ago. I also recall hearing the spark then which I can't now. all of which brings me back to coil - would that be reasonable? My assumption RE: the electronic ignition is that it either works or doesn't. (was visiting Dave Graves 14dna today and he thought the same)

Assuming that this makes sense and that I'm off for a new coil tomorrow - anything to look for?
 
That does make sense JP.
 
OK the story thus far.

1. bought a new coil - no difference

2. swapped out the rotor - no difference

3. swapped out the distributer cap - no difference

4. checked the oil level in the carb pot - check!

5. pulled the top off the carb - rubber looks intact and properly located.

Once again symptoms. will not start - turns and turns - backfires occasionally. leave it alone for about 3 minutes and it will start - reluctantly - and then I need to physically hold the throttle open - will not rev and when I let go it dies. and doesn't seem to be firing on all cylinders.

thoughts?

But, we now have 3 of 4 turn signal lights installed and working. Just the fourth and headlight connections (relay) to go.
 
Have you checked the timing? Sounds just like a Chevy 327 My brother had. The chain jumped one link on the spocket and it produced symptoms very similar to what you are discribing.
 
Sorry if this was covered before. But was this car running ok in the recient past. Has the distributor been out since?

Have you static timed it?
 
I'll look again - and even count the plug wires.

Car ran perfectly as recently as mid October.

Timing chain and tensioner - new
Distributer has not been out
Was timed and set with a timing light

all this began when changing to the new alternator which makes me think the problem is electrical. One thing I'm wondering about - when I was putting the dash back together I had two ends of the harness (at the steering wheel) reversed. The ensuing current melted my hazard switch and (I suspect) the ground in my alternator.

I would immediately suspect this except I am about 90% certain I did this
BEFORE the car was running

ah well - back to the drawing board
 
Double check your ignition timing. Perhaps you bumped and turned the dizzy while installing the alternator.
 
Ok, I will share this as you are such a nice guy, LOL.

Only one wire needs to be connected from the battery to the coil in order for the engine to run. If you think you screwed something up, back to basics.

There is a small wire going to the positive side of the battery, it actually powers the car. Take it off, disconnect or what ever. Run a hot wire from the plus side of the battery to the input side of the coil, take the other wire off first. Start the car by jumping the starter ie the starter switch will no longer work unless it is a bugeye, hehe.

You have now taken all the strange bits out of the system and only have battery, coil, condencer, points, plug wires and plugs to be concerned with.


Note: If you changed the timeing chain and this happened, how sure are you that you got it aligned properly when putting the new one on??????????
Remember fire and fuel it runs unless timeing is off badly.
 
JP,
Jack's idea is a good one. give it a try. Also start checking electrical connections. There is , or should be a ground strap on your spark box, make sure this is clean and tight. the same with the connections on the starter solenoid.
this pretty much has to be electrical. Your description of the weak spark is a dead give away.

Mark
 
thanks for the ideas - tragically at meetings today so I won't be able to check till tomorrow. Jack - just to confirm that you are describing a negative ground car.

Mark - by "spark box" do you mean the electronic ignition

and yes Jack - The timing was right - it ran strong - very strong before.
 
The first, second and third things to check are firing order, 1342. Then take out the plugs and take off the cap. Put it in second and nudge it forward slowly watching the #1 exhaust valve open, shut, then #1 intake open, shut, and the rotor should be approaching the post for #1 plug and the timing mark should be heading for TDC. As you nudge past TDC, the #1 piston crown should be topped out in view as the rotor is starting to pass the #1 post. Then recheck 1342 one more time.

What do you mean I "seem overly sensitive" on this issue!!??!! no further comment

Glen
 
JPSmit said:
Mark - by "spark box" do you mean the electronic ignition
Click to expand...

Yes the box usually mounted near the pedal box.
 
Not sure how your wiring is setup but it sounds almost like a car with a coil resistor bypass circuit and the resistor circuit is weak not being made when the ignition is released. Flooded, back fire, no - weak spark . check Those connections.
 
How are you making out JP?
 
SilentUnicorn said:
How are you making out JP?
Click to expand...

nothing yet - largely because I just got back from a cruise and a couple of days at Disney. Did I mention I hate winter!

saw some interesting cars - a Lambo and TR6 in the EPCOT parking lot. Many interesting Japanese in Nassau - including a goofy S-Type knockoff but economy sized. But by far the ugliest was a shortened '57 BelAir wagon sitting on a Jeep? 4X4 chassis with knobby tires and the original air cleaner sticking out of the hood. It had California plates so must be reliable but it was nasty!
 
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