A4 suddenly no start, I'm out of ideas.

[capnward]

still workin' on it

Thanks for all the response!
I reset the timing from #1 TDC, per the Moyer video and the Moyer manual. It had been a little advanced. No change, however. No sign of firing in cylinders, although i have compression, and #1 plug smelled like gas when i removed it. There is fuel puddled in the throat of the carburetor, not enough to leak out thru the choke lever, but enough to submerge the bottom edge of the choke plate. The float valve seemed to be working ok before I put the carb back together. I tightened the carburetor on well, to avoid air leaks. Fuel pressure is 3.5 or so and holding.
Spark is good from center wire of coil to head.
Here's something strange; When I tested spark to each plug (Autolite 308's) with a screwdriver in the plug wire socket, all plugs attracted spark except the #1. The #1 plug wire would create a spark when the screwdriver was near the head, but not near the top of the plug. Guess that means the #1 plug no longer works. Maybe all that removing and reattaching broke it. Would the engine start with #1 plug not working? I guess I need new plugs. When it suddenly ran rough, it sounded like a cylinder was off, but it came back on after a minute.The plug wires are several years old but still work, though the sparks from the ends of the plug wires are not as strong as the spark from the coil wire. Maybe that was because the connection to the screwdriver in the socket wasn't as good.
I don't know how to calculate system amperage, other than looking at the ammeter, which doesn't tell me much.
I tested voltage from +coil to ground with a multimeter; it was 12.4v when on, and decreased to 10.5v while cranking. The Indigo website says this is not unusual. The coil is the one that came with the Indigo AT-4D Electronic Ignition unit, bought many years ago, before they were sold with a 1.5 Ohm external resistor. The spare coil I have is a new Moyer coil with internal resistance. Is it OK to use with the Indigo EI? I will assume so, since Indigo has decided that the coil needs a resistor, and I don't think Moyer would sell a coil that was incompatible with Indigo EI kits. Maybe I should try the new coil, although the old one seems to be working.
And, maybe I should try a jumper wire from the + coil terminal to the unused #8-32 stud on the solenoid, as Indigo suggests, giving full voltage to the coil while cranking. (http://www.atomic4.com/balres.html)
I put some oil in the cylinders before retesting compression because the directions to the Carquest compression tester said:
"If the readings are low, or vary widely between cylinders, squirt one or two ounces of medium weight oil through each spark plug opening. Turn the engine over a few times to work the oil around the pistons. Retest all the cylinders as before. If readings are now more normal, then the problem is probably with the piston rings or cylinder walls."
I thought, why not? it couldn't hurt. I hope I didn't blow a gasket or something. But I guess if I had, the compression would be down, not up. I was curious to know how the readings would change. It sure didn't make them more normal. Extra oil in the firing chamber doesn't help starting, I'm sure. No doubt if it does start, there will be some smoke at first.
Dave; that browner (darker, anyway) fuel was definitely not right, and must indicate something... It came out of the carb after the engine began to run rough (sounded more electrical than fuel) a minute after starting normally, and then ran fine, but wouldn't restart. There are no brown additives, only a little MMO (2 oz. per 5 gallons) in the gas, and some in the crankcase oil (8 oz. in last oil change). It was brown, and a little cloudy. There was no water on the bottom of it in the jar. Four days later, it is less cloudy, with a little sooty stuff at the bottom of the jar. What could cause that? Gas in the crankcase? The dipstick doesn't smell like gas. Maybe it was because while monkeying with the idle adjustment and main jet while it was running rough, I made it run too rich, and that made the gas brown and sooty. Maybe crankcase oil from a non-firing cylinder got past the rings into the carb and mixed with the gas. Maybe gas that got into the cylinder and didn't combust made it back into the carb. After I cleaned the carb, and still no start, the fuel drained from the carb looked good. Seemed like it was the running rough that made it brown.
So, I will try, one at a time;
new plugs
new coil
jumper wire from + coil to accessory stud on solenoid.
If still no go, I will clean the carb again, but I didn't find anything there the first time, except for the brown fuel. Maybe I have the adjustable main jet set too lean, but it is 1 1/2 turns out from the seat.
I appreciate any thoughts you have.

[JOHN COOKSON]

Dave N. or somebody:
Would rust in the tank make the fuel appear brown with bits of crud in it?

CAPNWARD:
You must get clean fuel to your engine or it won't run. Suggest you try an auxiliary tank.


TRUE GRIT

[ndutton]

Yeah, auxiliary fuel tank for testing, don't use the existing filter either. I'd change out the coil for the new Moyer immediately, spark plugs too. Looks like we'll have to keep our fingers crossed on the ancient plug wires.

To learn more on electronic ignition and current calculation please visit this thread. You should check with Indigo but I expect they'll agree the information in the thread applies to their product as well.

[tenders]

I agree with your action plan. You have compression. You have some kind of fuel. You have identified another issue with the spark that could easily explain the symptoms. Fix that and see what happens. New plug wires may also be a consideration.

Are you 100% certain that the plug wires are installed on the cap in exactly the same places that they were when the engine was running, and that the plug firing order as you go around the cap is 1-2-4-3? I made the mistake many years ago, after a simple rotor replacement, of putting the wires back on in "stock" configuration, not realizing that somehow my distributor had been installed 180 degrees out of sync of "stock." It took me days to realize this, sitting on a rough mooring in NYC in the Hudson River. While trying to troubleshoot, I got sick over the side of the boat, drained two batteries that had to get dragged to my apartment and recharged in my living room, and almost blew up myself and the boat with exuberant use of ether. The signal I missed in that adventure was backfiring. That really should not happen with an A4. You don't mention backfiring, but if your wires were off by only 90 degrees, it might not manifest itself.

[JOHN COOKSON]

I Parsed this A Bit:

Dave; that browner fuel was definitely not right, and must indicate something... It came out of the carb after the engine began to run rough (sounded more electrical than fuel) a minute after starting normally, and then ran fine, but wouldn't restart.
It was brown, and a little cloudy. There was no water on the bottom of it in the jar. Four days later, it is less cloudy, with a little sooty stuff at the bottom of the jar.
If still no go, I will clean the carb again, but I didn't find anything there the first time, except for the brown fuel.

Here's what I came up with:

Brown, cloudy gas sits in a jar for a few days. The gas becomes less cloudy after a few days and some "sooty stuff" precipitates out. Implies what was causing the cloudiness precipitated out.
The same crappy gas sits in a carburetor and the rest of the fuel system a few days and "sooty stuff" precipiates out.
I see no reason to clean the carburetor again until you can supply it with clean gasoline.

TRUE GRIT

I don't know what is in your fuel. Let's just get your engine running. You can do a postmortem on the crappy fuel later if so inclined.

[capnward]

fuel from tank looks good

I guess you guys aren't buying my theory that the dark fuel that drained from the carb after it ran rough is an effect, not a cause. I don't understand how it got that way, and could easily be wrong. Fuel that came out of the hose before the carb looked fine. Fuel drained from the Racor filter was good. Fuel drained from the carb again after cleaning it looked good, too. Fuel pressure is good. Fuel sitting in the throat under the choke plate also looks clear.
I will continue to chase what sounded like an electrical problem (weak spark from bad coil, bad plugs, wires, or cap and rotor, suddenly faulty old EI module) until all parts of it have been ruled out, then I will address the fuel system again. Firing sequence is definitely 1243. Rotor is at 9 o'clock at #1TDC. Plug wires are 10 years old, but deliver some spark, at least. New coil went on today, new plugs and wires hopefully tomorrow.
There is a slow drip from the freeze-out plug behind the coil on the block, I noticed today. Could be the source of the slow coolant loss I've been noticing all summer. Maybe it was spraying the bottom of the coil when engine coolant is pressurized, but it was too small to be seen, and I watch the engine run, a lot. Didn't see any geysers when it ran rough. I will replace the freeze-out plug, but first I want to see if the engine will start.

[yeahjohn]

So has a fuel issue been ruled out? It seems like this could very easily be something in the gas or in the carb. Obviously sense the engine runs so much that would be a strange occurrence, but something could have blocked up the carb, old hose etc?...

[randoo]

I had similar problems which turned out to be caused by water in the cylinders. Also contributing was old gas.

Right or wrong, i pulled the plugs, and using a remote starter (so I could be right at the engine when I cranked her), cranked the engine several times with towels over the engine, until all evidence of water was gone. If you don't use the towel and there is water, you will "pump" all that water into your cabin! That is ugly. I then put MMO in each cylinder, let er sit a couple of hours, then cranked er again. Changed the oil 3 times, retimed 'er, used good gas plumbed from my aux tank, and she fired right up.

If you try this, be sure your thru hull valve is shut so it won't pull water. I also flushed the fuel system and installed all new filter elements.

Also, be sure your new plugs don't have cracked ceramic. I damaged my plugs several times when reinstalling. Doesn't sound like your problem, though

good luck

[capnward]

still no start, after new igniton stuff installed

Update;
Now my A4 has new coil, plugs and wires, cap and rotor, but still no hint of firing. Good spark from coil to head, like before all that stuff was replaced. I thought it was electrical, because the fuel to the carb, drained from the carb, and in the throat of the carb, and the carb and jets all look clean. Also because the sound the engine made when running rough at the beginning of this non-starting episode sounded unlike previous fuel starvation sounds. I thought maybe spark wasn't strong enough. Timing is reset according to Moyer instructions, choke closes completely. Adjustable main jet is out 1 and 1/2 turns from seat, idle screw is 1 turn out. Compression is good, water valve is closed. Fuel pressure is good. Plug leads are in 1-2-4-3 order. Distributor has not been removed.
If the 10 year old Indigo electronic ignition module is shot, would it still create a spark?
If there is water in the cylinders, how do you tell, if plugs smell like gas and have no water on them, and there is no sign of water on the dipstick? Crankcase oil is not grey.
I have already checked out the fuel system, (draining gas from water separator filter, no water in it, disassembling, inspecting, and cleaning the carburetor and jets, replacing inline filters, checking for good clean fuel flow into the carb) but I will look at all that stuff again. I don't know what else to do. I could hook up another tank with fresh fuel in it, bypassing all filters, hoses, and the fuel pressure gauge, but the fuel system I have looks clean, with clean fuel coming through it. Seems redundant and useless to do that again, but it wouldn't be any worse than replacing all ignition parts when the spark was good to begin with.
Something I noticed when checking spark from a screwdriver shoved into the end of each plug wire, and held near each plug, is that the spark is weak compared to the spark from the big coil wire to the head. Maybe this is normal. The screwdriver connection is not too secure, so that may be why. The cap and rotor are new.
Curiously, I can't get the #1 spark plug wire to spark to the #1 plug with a screwdriver, even though it sparks fine to ground at the head. I thought changing the plug and wire would fix it, but no. Other plug wires will spark at their plugs, but not #1. This was also the case before all the ignition stuff was replaced.
I have now ruled out everything at least once. I have spark, clean gas and carb, good fuel pressure,compression, and timing. No water or crud is in the bottom of the Racor water separator, and the inline filters are not restricted. Since in my experience, non-starting has been a fuel issue, I will check the fuel stuff again first.

[edwardc]

Boy, this is shaping up as a puzzler for the Car Talk guys!

Seriously, though, I keep coming back to your description of the spark. Strong at the coil wire, weaker at the plug wires: that would seem to implicate the rotor, cap, or plug wires. But you've replaced them all!

Time for grasping at straws. I'm not familiar with the Indigo EI ( I have the pertronix), but is it possible that the optical shutter gizmo that sits on the distributor shaft has somehow come loose and rotated on the shaft? This would not only cause bad timing, but if it were far enough off, the rotor wouldn't even be close enough to the plug contacts inside the cap, forcing it to jump to it, resulting in a weak or no-spark situation.

Have you tried a massive amount of distributor adjustment, something on the order of + or - 45 degrees? If this (farfetched) theory is true, that should produce some kind of firing response.

[Dave Neptune]

capnward, try a spritz of "motor crack" if that does not start it, then I'll bet the timing is off.
What type of EI?

NOTE, your rotor pointing a 9 oclock has nothing to do with timing unless you are on TDC and start your wiring from there. The distributor may not be in the same position as before and that position may not be 9 oclock.

Dave Neptune

[JOHN COOKSON]

NOTE, your rotor pointing a 9 oclock has nothing to do with timing unless you are on TDC and start your wiring from there. The distributor may not be in the same position as before and that position may not be 9 oclock.
Dave Neptune

Rotor is pointing at 9 oclock when viewed standing at the front or the back of the engine?
Betcha you're 180* off on the timing.

TRUE GRIT

[ndutton]

There's something you've checked and either pronounced good or assumed good that isn't. None of us are there so we're giving it the best we've got based on the reports. The suggestions from knowledgeable members of timing problems are because we've danced this dance many times before. It's become all too familiar.

My thoughts - or guesses - are the original problem was probably an ignition component. Which one, I'm not sure but they all have to work together. There's every chance you've replaced or otherwise resolved the original problem but now there's another problem(s) due to all the adjustments, guesses, etc. over the last week.

I'd start over and make the systems right instead of searching for an elusive gremlin. In the case of ignition it's not all about having spark. It's about having a good quality spark at precisely the right time. With the fuel system it's important to have clean fuel but that's no less important than clean fuel at the correct concentration with air.

Nothing is off the table right now even if it's been checked before. The only thing that's known for sure is the engine doesn't start.

[capnward]

Huzzah!! She starts! It was oil in the carb.

Gosh, I love happy endings. While taking apart the carb again,I saw that what I thought was gas in the carb throat was really oil, pushed there when I put some oil in the cylinders to see if it would change the compression test. It brought the pressure numbers way up, but not equally. A useless exercise. Curiosity strikes again.
I should have known. The same thing happened to me when starting up in the spring. I put MMO in the cylinders before starting, thinking that it would lubricate them and keep the rings from scouring until the rest of the oil worked its way in there after months of inactivity. The engine wouldn't start then either, and the red dye started dripping out of the carb throat. After cleaning the carb, it started.
As I recall, I did the second compression test with oil added before I changed the cap and rotor. Replacing cap and rotor may have fixed it, but I had created another reason for it not to run. Then there were the new coil, plugs, and plug wires, and reset timing, all to no avail. Any of those ignition system changes may have been the fix, but getting the oil out of the carb finally did the trick, enabling the fix to work.
Of course, the mystery remains. What was the original problem? Since the coil purchased with the Indigo EI kit 10 years ago didn't have an external resistor, and Indigo has since then decided to include a resistor, maybe the coil finally got weak, although it was creating what looked like adequate spark.
Also, I still don't get why spark from the plug wires to the plugs via a screwdriver is much weaker than spark from the center coil wire to the head, even with new coil, cap rotor and plug wires. Or why the #1 plug wire won't make a spark to the #1 plug, but will to the head, and the other plug wires will spark to their plugs.
And at one point today when the engine was idling, and I either made it too rich or too lean, it stopped, and all electrical power went with it, which was a problem I thought I had solved weeks ago by tightening a bad ground connection. Power came back on within a minute. Probably fodder for another thread.
But I am willing to leave these mysteries alone for a while, because my good ol' trusty A4 is again running. And it restarted, twice! There was a lot of smoke out of the exhaust until the oil had burned out of the cylinders. It took a while to tinker with idle jet screw and main jet screw, and turning the distributor to get it sounding ok. Plus after an hour or so of running, it got smoother. Now when tied to the dock, I am getting 1650 rpm under load, with a vacuum reading of 5. In the spring I will put on the new Indigo prop and hopefully get the rpm up around 2000 with a load.
I feel much better now. Thanks a lot for the ideas and support, fellas.

[zellerj]

Condenser

Did you change the condenser? Usually this is done the same time as points and roter and cap, but you did not mention it.

Jim