TR2/3/3A TR3 No spark - Ignition mystery

[Jim Lee]

Hi all,
I have what appears to me to be a really strange ignition problem on my TR3. It's been running like a top for the last few years with a Pertronix ignitor in place of the points. Just this year I was having this strange experience where it would start up and run beautifully for varying amounts of time usually at least half an hour. Long after warm up. Then it would start missing on a couple of cylinders as if I was running out of gas. If I was close enough to home I could usually nurse it home with my fingers crossed. A few times it would just stop altogether and I'd manage to get it off the road...wait around a few minutes (maybe 5 at most) think about what a drag it was going to be to leave the car here and get a tow truck. Try to start one last time and it would start up? Get it home safe in the garage and tell myself I would clean out the gas tank and lines, replace my two filters because this had to be a fuel starvation problem. I've made some progress at least in that I now know that it is definitely not a fuel problem. I have a Facet electric pump and you can hear it about a mile away ticking. It is pumping plenty of gas to my carbs. My float bowls are pristine and not stuck. My spark plugs are wet when I look at them.

Finally had to get a tow the other day when it went through the same series of symptoms except that this time it didn't start up again. Since then its been in the garage and I have replaced these parts:
Plugs, wires, distributor cap, Petronix positive ground ignitor unit, coil and I have replaced the white ignition wire that runs from the ignition key to the fuse box and then the wire that runs from there to my Petronix box instead of the coil as I believe it would if I still had points. I measure between 6 and 7 volts at the negative side of the coil when I am cranking the engine (from the solenoid switch in the engine compartment). I measure very close to the full voltage of the battery when I turn the ignition on at the ignition wire that attaches to the black wire on my ignitor. If I remove the wire that comes from the coil to the distributor and hold it within a half an inch of my valve cover I can see a small blue spark but nothing very dramatic. I used to be able to detect voltage with a timing gun that I have on one (only one) of the plug wires but now I don't detect any voltage anywhere in the plug wires or the distributor wire...unless I completely remove it as above described and ground it to the valve cover. If I remove a spark plug with the lead attached and crank the engine with it grounded against the engine no spark at all. Nothing.

I replaced the ignition wire from the key switch because when I first installed the new Petronix Ignitor there was a wire burning, the black wire that goes to the ignition white wire of the car when I first turned on the ignition before I even had a chance to get up front and turn it over. It heated up as if I had connected the Petronix wires backwards but they were attached just as I had my original Petronix Ignitor. Black/white wire to the negative side of the coil, black wire to the ignition wire. It does this heat up deal once....then I rush over and turn off the key...blow the smoke away...wonder what the heck is going on....turn the key on again and no smoking. I replaced the ignition wire because I was thinking that I must have a shorted ignition wire. I guess not because the very same thing happened after I replace the ignition wire. In any case what I am planning on doing tomorrow is getting some new points and condenser and go back to the points....which I have never used on this car. From what I have heard 6-7 volts ain't enough for the coil to get the proper voltage up. Remember this is a brand new coil, and I have switched between the two with the same results.

My current hypothesis is that I have fried two Petronix Ignitors, my original and the new one but I have no idea why. And they work no differently now then they worked before they each heated up and started smoking. Same exact voltage to the negative side of the coil on cranking. What kind of voltage do you all get at the negative post of your coil when you are cranking your tr3? Am I correct in thinking that 7 volts isn't enough?

I am absolutely stumped why one Petronix Ignitor that has served me well for years would stop working in the weird way that it did, if it did. Has anyone had an aftermarket ignition module imitate running out of gas on the road and then start up again? I thought that they either worked or did not. That could still be the case but I haven't a clue as to what else is involved if the coil is good, the wires are good, the cap, rotor.....all this stuff was running like a top except for the aforementioned strange experiences on the side of the road and finally the tow.

I am wondering what else is in the Ignition system that I have missed or what else could be affecting the system in that the plugs are not getting any spark at all?

There has to be something really simple I am missing here.
I'm just glad it's not running at all though as oppossed to running like a champ for half an hour and leaving me out on the side of the road.

Any ideas would be most appreciated.

Thanks very much,
Jim Lee

 

[Guest]

Jim,
I won't attempt to match the breadth or scope of your post, quite well done I must say, except to say that I, too, have had electronic ignitions ( 3, all Crane/Allison ) shut down for no reason whatsoever. Went back to traditional points and have zero problems. Sorry you are having all the trouble.

Bill

 

[trrdster2000]

Jim, I am going out on a limb here and will properly get laughed off the forum, but you have somehow put a positive charge on your plugs,(if you have positive ground, reverse that). Take a lead from the battery, which ever is your ground and touch each plug and the distributor. I know, it sounds crazy but had it happen twice in the last 40 years. You should get a spark when you hit these items, if not touch the block right next to the plug and check the ground wire from your engine block to the frame as this was one of the problems solution. Wayne

 

[Jim Lee]

Hi Wayne,
It doesn't sound any less crazy than what I am seeing which with my extremely limited electrical knowledge, appears to be the result of polarities being transposed. Like what your wife always asks you after you just spent hours rolling around on a cat litter/oil filled garage floor with a splitting headache trying to figure out where the latest electrical gremlin is hiding out. "Did you switch the battery wires dear?", has probably been the beginning of the end of many marriages and partnerships.

What I am seeing though is exactly what one would see, don't ask how I would know, if you were to mix up a pair of jumper cables. They get real hot and if you don't stop the current flow by flinging them off into the nearest bushes, usually your neighbors who is staring at you from the front window in awe, they eventually melt down at the weakest link just like a fuse. On one of my attempts the black wire from the Petronix Ignitor actually did get hot enough to melt down so that it is now a fraction of the length it once was. What I find beyond crazy is that once I rush around to turn off the ignition...remember I haven't even had a chance to crank the engine, this smoke signal begans as soon as I turn the key but only on the first time that I install another Petronix ignitor. I have my old one and a new one, probably both fried now, that I switched back and forth a few times for fun. After the initial heat up, smoke out, melt down....unless I have actually severed one of the wires from the ignitor I, in my electrical wisdom, figure I have nothing more to lose and wait a few minutes to catch my breath and turn the key on again promising myself and the Lucas Gods that if it starts smoking again I will untwist the twisted ignition wire that connects to my now cooled down Pertronix Ignitor. Lo and behold it does not heat up or do anything out of the ordinary after the initial key turn. And I can detect what I think is a very weak ass spark coming from the center of one of my brand new (3.x ohm resistance) coils if I remove that wire from the center of the distributor cap and ground it to the engine. Absolutely nothing though going to the spark plugs that I can detect. BUT I can also detect varying amounts of voltage getting through the PI (Petronix Ignitor) to the negative side of the coil when I crank the starter. It usually varies from 6-7 volts. Which if I recall correctly is exactly what it did before
I messed around with anything immediately after my tow home. In fact I believe it was measuring even less, like 3-4 volts at the negative post of the coil before I touched anything.

I was thinking of twirling the coil around because it seemed so obvious that somehow, some way, the polartiy was crossed. But I have restrained myself for now since after the initial install of the PI I don't get that reaction and it IS a positive ground car and I do have the exact same PI that I have been using without any problems for the last umpty-ump years....not to mention a new one that is exactly the same.

I'm willing to try anything as I am already pretty callused to smoke coming up from my engine compartment. At least I am relatively safe in my garage with a fire extinguisher at hand and not on the side of the road worried about getting sucked away by a semi truck. I will definitely double and triple check the ground wire from my engine block but I am fairly certain I have done that.

My question is if I take a wire and attach it to my postive ground terminal on the battery am I to remove all plugs leaving the wires on and just touch the electrode with that wire until I see a spark? Also where exactly on the distributor would I touch the ground from the battery?
To the top of the rotor?

Believe it or not this is the first real problem I have had with my TR's electricals. And beleive it or not it was running like unto a sled on snow right up until the recent tow....not counting the pauses on the side of the road I had to take to let something cool down.....I guess.

I'm wondering if I have managed to put a reverse charge on my plugs and/or distributor whether putting in points would make any difference at all.....other than perhaps getting a lesson in how to burn up points in less than a few seconds.

Thanks all for any advice or ideas.

Jim Lee

 

[Geo Hahn]

Geez Wayne, that borders on the mystical -- but where electrons are at work strange things can happen.

Your voltage at the distributor side of the coil is fine, suggesting that the coil is okay.

Correct coil orientation for a + ground is to have the white wire to the - terminal, the white/black dizzy wire on the + terminal. Though even if reversed it wouldn't cause your problem.

You are on the right track with putting in points and then assessing things. This will allow you to look for a spark when the points are prised open, etc.

By now you should have 2 of everything (expect perhaps points & condensor) in the ignition system... that's good. Once you get it running put all the spares in a bag and toss it in the boot. I carry all that plus a spare distributor.

You can hold the entire ignition system in one hand and replace it all in much less time than it takes to get a tow truck. Since this is (in my experience) the air/fuel/spark component that is most likely to let you down, having a spare of everything in the boot seems prudent.

If I had to guess -- I suspect you're correct that the Pertronix has failed. Let us know the final result.

 

[Jim Lee]

Hi Geo,

So 6-7 volts at the negative side of the coil when cranking sounds normal and healthy?
==========================================
Your voltage at the distributor side of the coil is fine, suggesting that the coil is okay.
=====================================

Here I assume you are talking about the connections when I put the good old points back in. What I have now is the white ignition wire going to the Petronix Ignitor black wire and the black/white Petronix wire going to the negative terminal of the coil.....not that it's done me any good recently. It used to work...in what I am beginning to think was perhaps a parallel universe BT (Before the Tow).
=========================================================
Correct coil orientation for a + ground is to have the white wire to the - terminal, the white/black dizzy wire on the + terminal. Though even if reversed it wouldn't cause your problem.
=====================================================

I am nervous about just burning up the points if, as it appears, I have managed to reverse the polarity on something. Then again being nervous has never stopped me from screwing up something before. Is there a way to test the polarity of my plugs besides the 'bull in the china shop' approach of twirling the coil around? I'm thinking I can't do much more harm than I have already done....although those are often famous last words.

Thanks everyone.

Jim Lee

 

[Geo Hahn]

[ QUOTE ]
So 6-7 volts at the negative side of the coil when cranking sounds normal and healthy?

[/ QUOTE ]

Oops, sorry -- I was thinking the other side (positive or CB terminal). 10 VDC or so would be about right for the negative or SW terminal though I'm not sure that your 6-7 VDC is a problem.

Yes, all references I made were to a stock points ignition, I know nuttin' about Pertronix. I am also unfamiliar with this concept of polarized plugs so cannot comment on those.

Even if the coil is reversed the engine will run okay. That reversal isn't going to 'smoke' anything.

If you set it up with the stock points arrangement, set the timing and it still doesn't run then routine diagostics should isolate the problem fairly quickly.

 

[sp53]

Hi Lee I think the problem might be the coil. They can warm up and change. The coil can actually short out and take the path of least resistance to ground (arch to the block, or on a tr3 the metal water pipe from the heater) when warm-- then cool off and after a few minutes (10 to 30….) and fix itself for a while. When this happens and you if you have an electronic ignition and because most electronic ignitions are sensitive to shorts they are probably both toasted. So now you probably have two problems that are kinda related—bad coil and shorted out ignition. I would go back to points as they are tuff and easier to fix. Moreover, they are original, keeping with tradition. Perhaps if you turn the lights down in the garage you can witness the coil shorting to ground when you crank it. If you put points in it might start and give you the same trouble down the road with the prince. Or you could replace the coil and go to points and be at one with the prince.

George

 

[Dave Russell]

Hi Jim,
From the above descriptions it is still not clear to me how you have things connected. For clarity, I am not going to reference wire colors except for the two Pertronix wires.

Basic wiring for a positive ground Pertronix:
1- A wire from switched neg. 12 volts to the Pertronix black wire. No other connections.

2- The blk/wh wire from the Pertronix to the coil - (neg.) terminal. No other connections.

3- A wire from the coil + (pos.) to ground. No other connections.

4- The coil should be three ohms as you have said.

If there are any other wiring connections, do not connect them until things are sorted out & treat them as separate problems.

If there was smoke, the Pertronix module is likely damaged.

The original wiring for points should be:
1- A wire from switched - 12 volts to the coil - terminal.

2- A wire from the coil + terminal to the distributor side terminal.

3- A condenser connected internally across the points.

4- Make sure that the points connection insulating washers inside are in the correct positions & that the points are not permanently grounded.

I just hope that I haven't confused the issue more. Good luck,
D

 

[Jim Lee]

Hi George,

I was sure it was the coil heating up and shorting out until that was the first thing I replaced and it made no difference at all. Before I changed the wires, plugs, distrib cap the symptoms (cylinders missing and then finally exiting after 30 minutes....letting it sit allowed it to start up again.....) pointed directly to the coil.
So when I started on this Post Tow (PT) odyessy (sp?) the very first thing I did was to run down the street and get another coil before I changed anything else.

I am still bitter that the new coil did not fix it right up. But the sequence of replacement was 1). Coil 2). plugs 3). wires 4) distributor cap, rotor 5) Petronix Ignitor....I saved the most expensive (~$90) for last. I have another coil in my '63 Tbird that is made for the Petronix but it is working on that much larger V8 engine. I think that I have already tried that coil with out any difference but I could test that for the resistance of 3 ohms or thereabouts and swap that in if I haven't already.
Three bad coils, two of which were running fine BT and one brand new would be very difficult for me to take psychologically. That would be a clear conspiracy.

Thanks,
Jim Lee

 

[Jim Lee]

Hi Dave,
Yep. What you have here is exactly what I have been wrestling around with to the letter. I got some new points and a condenser tonight and am going to put them in as soon as I can get a few hours of uninterrupted time in the garage. I have never run the car with points, got the electronic ignition module when I brought the car and it was running fine for a few years with that...up until that last bend in the road. I guess it is time to go back to basics and return to the Natural Laws of Lucas before I blow myself up. If the points work I will be very happy but still absolutely clueless as to how I have apparently switched polarity somewhere, somehow, and wasted one, maybe two of the Petronix things that I was such a firm believer in. I also have one on a '63 Tbird that I have and it has never given me any trouble. The thought just struck me. If I could get a working distributor I could mount some extra points on that and I would be able to carry around an entire redundant ignition system under my back seat to ward off tow trucks.

I'll keep everyone posted on how the points go.

Thanks very much,

Jim Lee

 

[MDCanaday]

I , for one, am glad to change my points&condenser every 20k just so I can avoid this kind of wierdness. Infact, I have seen more people stranded by bad ignitors than I have ever seen by burned out points. K.I.S.S.
MD(mad dog)

 

[jayhawk]

I chased similar problem-- not quite to the point that the car would die but mighty close. Checked and replaced stuff for 2 years and finally found a clip on the voltage regulator that was making a bad connection. I know it sounds too obvious but the top of the clip looked ok but when I pulled it off the wire attaching to the clip under the insulation was just carbon and I couldn't see it. You might just for kicks check all clips/contacts in the circuit for good contact.

 

[trrdster2000]

Jim, as you can see, lots of problems with our Lord of Darkness and no one answer. If you go to points, rather than carry around a whole distributor, just get the plate off an old one, it's a two screw and one spring on the vacuum change over, of course you set it up before hand. Now to what I had a weez kid do for me was the Capacitive Discharge system where you use the points but get electoric ignition and he put some kind of switch over box with a condenser in it so if the CD went bad I just switch back to regular. You can tell the difference between the two and the CD is much better, only trouble I don't think you can even get the CD any more. We were going to make a bunch and sell then but with all the new stuff it would have been hard to compete. Not helping you, am I?? Sorry! I get carried away, if you have already changed plugs you should have gotten the ground back in right order. Hope to hear you have it right in a day or so. Wayne

 

[Jim Lee]

Wayne,
I haven't carved out the quality garage time with my TR to put the points back in but I'm wondering if you or anyone else has any tips or hints for me in reinstalling these without screwing too much up. I have the reprint British Red manual and the exploded view seems to make sense but I am wondering if there is any place on the web where I could see actual pictures of the points/condenser in situ and maybe even a rudimentary guide for a non-points person like me to set them up. I have replaced points in an old Honda motorcycle so I am not totally unfamiliar with the process but any additional information would sure not hurt. I am having nightmares about that smoking ignition wire with the very same hook up that I had before (with the Pertronix Ignitor module). It really bothers me that I don't know why both modules (new and old) heat up the wire and the module when I first turn on the ignition. After the first turn it's fine (notwithstanding the 'no spark' condition).
"Fine" in the sense that it doesn't melt the wire that is connected to the Switch (#9 white wire) in the schematic I have...that normally goes to the distributor. Doesn't that mean that I have a short some where? If I do have a short why does it only heat up and smoke and shatter my confidence on the first turn of the key/ignition? Once it gets past that point, no more smoking? I have replaced the ignition wire (#9 white as above) that goes from the switch to the push starter in the cab to the terminal at the regulator and then goes to the distributor or ignitor. So I don't understand how I could have a short in that line at least. I was staring at the schematic last night and wondering if I could have a short anywhere between that switch wire and the negative (It's still positive ground system) terminal of the battery. And if there is I best find it before I melt something else down or just for some sort of peace of mind while I am driving down the road.

What I am thinking is that if I have a short or a reversed polarity, will it not still melt down that switch wire when I stick the points back in on the first turn of the key?
I guess another way of putting my question is what is the actual path of the juice before it gets to this SW switch wire that is normally attached to the SW terminal of the distributor? Could there be a short anywhere in the electrical system or do I get a reprieve and only have to worry about the white ignition wire circuit?

The first thing I am going to do, which I am sure I have done in the recent past is to double and triple check the three ground points I see in the schematic to make sure they are doing there thing. I think I would feel better if the wire and Petronix do-dad smoked every time I turned the key on instead of just the first time. Maybe I could have an assistant with a soldering iron hidden beneath the garage floor.......maybe not. The weather is so nice out here in NC right now it's killing me but I'm keeping the faith.

Thanks all,
Jim Lee

 

[trrdster2000]

Hi Jim, right about the weather, going to grab the golf clubs very shortly, but to your problem, lets do this, take the wire from the switch off the coil, take a wire from your neg. side of the battery and put it right to the coil, neg side,this of course is after you get the points set up, don't cut the switch on, push in the outside starter button and see if it will fire up. Don't tell anybody about this because so many of these cars were stolen like this. Now you have taken the switch out of play. When it starts just unplug the wire and put your switch wires back on, cut the switch on and if it smokes you know where to start looking. Be sure and check the wiring harness for any signs of melt down, it would not be the first to have the insulation burn off wires inside the harness and cause a major fire. I use to carry a 3 foot wire with clips just for this reason when helping out someone with wiring problems and not sure what they did before I got there. Wayne

 

[Yellowdog]

Hi Jim,

For the first time in my life, I might have to agree with a jayhawk. While the initial problem sure sounds like a coil issue, I cannot help thinking that something (a wire or connector) is loose, corroded, or worn through and is at the root of your problem.

I created a "smoking on first turn of the key" mess for myself last spring after completely rewiring our '78 Ski Nautique, granted, it is a boat but engines, ignitions and electrons are all common. Everything was wired correctly, just one loose connector and I smoked the lead to the distributor. Apparently after heating up and smoking the first time, it would settle in with a stable enough connection to work?

Check the grounds or hots or whatever term the negative earth system uses under load, not just for continuity.

Oh yeah, I know how you know about reversing polarity on jumper cables, but I'll keep it to myself.

Good luck. . . .

 

[Geo Hahn]

[ QUOTE ]
...am wondering if there is any place on the web where I could see actual pictures of the points/condenser in situ and maybe even a rudimentary guide for a non-points person like me to set them up...

[/ QUOTE ]

'in situ' eh? Here's a pic of mine...

The place where one can most easily go wrong is in the sequence of nylon/plastic/fibre washers and the 2 wire terminals that go under that nut. But even if you do it wrong nothing smokes -- just nothing works. Basically, if done correctly the points' spring is not grounded when the points are open.

I can't be specific about the assembly sequence on that nut because different sets use different parts -- some have a kinda one-piece collar and washer, others use a couple of pieces to do the same thing.

The suggestion of using a jumper wire from the - battery post to the - coil terminal to bypass the switch is good to know and will leave the whole ignition switch circuit out of it until you get things going. Make that the last connection you do before you try to start it and the first you disconnect when done (disconnecting it is how you stop the engine if it starts). Oh yes, be sure you're in neutral before you push the solenoid button... I bet we've all run over our own foot a time or two.

 

[Jim Lee]

Thanks Mr. Hahn,
That is very much 'in situ'. I've got the two wired right on top of the metal spring thing pivot, not to be too technical, and then the nylon deal pointing down so it fits in and then a washer on top of that and I managed to get the nut on without dropping in the bowels of the distributor. I have to plugs out and in 4th gear I can move the rotor around and play with opening the points to betwixt .014 and .016 inches gap. I am pretty sure that I have the engine at top dead center or thereabouts. I didn't see any notch on the pulley but I did feel a distinct bump with my finger on the engine side of the pulley which is matched up with the real obvious pointer above. The rotor is no pointing exactly at Plug #1 but it is just a few degrees counter clockwise of that. I've never set points before except a long time ago on a motorcycle using a test light but I am thinking, hoping, praying I will be in the ball park by being at TDC and with the cam making the points fully open the gap being as above. I haven't tried to start it yet because it would be way too depressing tonight if it didn't start...or just smoked like it does with the darn ignition module that I have cast aside. I'll go for it tomorrow.

By the way, it's still positive ground, so my switch wire (originally white #9 on schematic) should go to my "-" post on the coil and my "+" post from the coil goes to my distributor (LT?) right? Another aside, I noticed that one of the contact points looks like a washer as oppossed to being a solid circle but I see this on more than one set of points but not the original ones that were used by the previous owner. Is that normal? I thought contact points had to be solid circles but what I don't know about points could fill a library. Oh and the other reason I am not goin to try to start it tonight is I promised myself that I would check all the grounds before I turn that key again. Or maybe I'll just jump it off the battery as suggested above in case my ignition switch is conspiring against me.

Thanks all,
Jim Lee

Thanks to all.

 

[trrdster2000]

Jim, the wires for the coil and dizzy are as you have them, so go for it!! Jim, I really would jump it off, it will help your ego when it starts and then look for the other problem. The new points are made up with the washer look and I believe this was done to keep the build up of a little spike that always seems to develop in the middle of the old style. Wayne