Everything worked great for about a month and then suddenly a misfire developed at moderate rpm. It went right from working great to misfiring in 1 second.
The distributor weights are advancing the timing as rpm's increase.
I've tried connecting the + wire (red) from the ignitor to both the input for the noise suppressor and the coil itself.
I had a look at the trouble shooting tips on Expedition Imports site. I tried moving the ignitor closer to the magnetic ring.
The problem has not gone away. My thoughts that the condensor wire had something to do with it were wrong, although it did work fine for a short time after disconnecting it. The condensor shouldn't be doing anything at all now anyway, right?
So it would seem that I've either had the new coil or the new ignitor suddenly go bad on me. I'm leaning toward the ignitor.
Is there a way to test it? I guess I'll have to call Pertronix and see what's up.
I also just noticed that the box that the flamethrower coil from the kit (40611) says " High Performance 12VOLT Universal Ignition Coil". Is it ok for 24 volt use?
The ignitor is UM-161.
This conversion kit was supposed to make things more reliable...
Scott at Expedition Imports - any suggestions?
__________________
Two Tone
______
Reading the instructions - a sure sign of weakness and uncertainty.
In general the following is true......the ignitor either works or it does not. There is usually no "in-between." Considering the conversion was working well, and you suddenly get a miss, it's not likely the ignitor.
#1 - After install when you did the voltage test what was your input voltage to the coil at moderate/high RPM?
#2 - Do you have both the black and red wire running completely out of the distributor, or have you spliced the black wire inside the distributor? The condensor has NO bearing whatsoever on the system.
#3 - What cylinder are you missing on? The same cylinder each time, or different cylinders. The same cylinder and I would be looking towards a cap/wire/plug issue. If it is missing on different cylinders I would be looking towards the coil, or magnetic ring not fully seated. Simple test....take your timing light inductive pickup and put it on each wire while the truck is missing and see which cylinder it is....
#4 - 6V, 12V, 24V, 36V - doesn't mean much on a coil. As long as you are running a 3 ohm coil that can handle the input voltage and has it's corresponding output voltage you are good to go. Your ignition system does not work on 24V, it runs between 17-21 volts.....hence the reason to check the ballast resistor output voltage on installation. Pertronix themselves spec'd the complete ignitor/coil combination after testing a complete stock ignition system. The 40611 is what they called for.....I could have them make up pretty 24V boxes and jack the price by 20-30%, but it's not our style.
#5 - What is your timing set at? Double check it.
#6 - With the minimal information provided, it is difficult to armchair diagnose your problem. Make sure it is an ignition problem, and not something such as a sticky valve, etc.
#7 - Does the problem happen everytime even when cold? IE.....does it take a while to start showing up, or immediately. On overvoltage problems we see the coil work fine when cold, but after running a while it may start missing...usually occurs right before complete failure. Rule out voltage issues immediately as if the coil fails, it WILL likely take out the Ignitor immediately.
Everyone has their opinion on the kit. Considering that the conversions have been on the markets for over 8 years, with a combined "test group" of well over 1500 installations...the kits are definitely a proven upgrade. However, it is not a silver bullet and is only going to work as well as the rest of the system.
You have some homework, report back and let us know the answers to the above.
Cheers,
Scott Ingham
Expedition Imports
Last edited by expeditionimports : 05-15-2008 at 08:52 PM.
I just found your other post...would have been appreciated had you simply dropped me a PM and asked me to comment their....know we have two threads on the same problem. Anyways.....
How much did you shorten the rotor for installation? When the rotor is installed what is the gap between it and the magnetic ring. My guess is the reason why your "condensor" fix seemed to work was because when you re-installed the rotor/cap it was seated down properly. I'll bet you have either not taken enough material off the rotor and therefore it is not fully seating, or you have taken too much off and it is know coming off easily....
.
.
Hi Scott, I really appreciate your getting right back to me. You're right, I should have PM'd you rather than start a second thread. I didn't think of it at the time. I've never done one. I couldn't edit the title of the other thread and I wanted to get your attention. Selfish of me.
Anyway, maybe this thread will help someone else with what to check if they have a problem:
Quote:
Originally Posted by expeditionimports
Howdy Howdy,
In general the following is true......the ignitor either works or it does not. There is usually no "in-between." Considering the conversion was working well, and you suddenly get a miss, it's not likely the ignitor.
OK, thats good to know.
Quote:
Originally Posted by expeditionimports
#1 - After install when you did the voltage test what was your input voltage to the coil at moderate/high RPM?
I remember seeing 18.9 ish, but I don't recall that I revved it up. I'll check it today.
Quote:
Originally Posted by expeditionimports
#2 - Do you have both the black and red wire running completely out of the distributor, or have you spliced the black wire inside the distributor? The condensor has NO bearing whatsoever on the system.
Both wires out through, no splices. Originally I had just put the condenser wire back on its screw to keep it out of the way. I thought the same thing.
Quote:
Originally Posted by expeditionimports
#3 - What cylinder are you missing on? The same cylinder each time, or different cylinders. The same cylinder and I would be looking towards a cap/wire/plug issue. If it is missing on different cylinders I would be looking towards the coil, or magnetic ring not fully seated. Simple test....take your timing light inductive pickup and put it on each wire while the truck is missing and see which cylinder it is....
That is something I didn't think of. I know it misses on #1 from using the timing light. I'll check other cyls with the light and see what I get. That should help narrow it down a lot. The mag ring is flush with the top of the ignitor and seems secure.
Quote:
Originally Posted by expeditionimports
#4 - 6V, 12V, 24V, 36V - doesn't mean much on a coil. As long as you are running a 3 ohm coil that can handle the input voltage and has it's corresponding output voltage you are good to go. Your ignition system does not work on 24V, it runs between 17-21 volts.....hence the reason to check the ballast resistor output voltage on installation. Pertronix themselves spec'd the complete ignitor/coil combination after testing a complete stock ignition system. The 40611 is what they called for.....I could have them make up pretty 24V boxes and jack the price by 20-30%, but it's not our style.
Understood. Scott, is there a test I can do to check if the coil itself has gone bad?
Quote:
Originally Posted by expeditionimports
#5 - What is your timing set at? Double check it.
14 deg BTDC at 850 rpm. I tried varying it yesterday between 10 and 18 for short runs with no change in the miss. The advance is working but I didn't do an exact test as to what maximum advance is.
Quote:
Originally Posted by expeditionimports
#6 - With the minimal information provided, it is difficult to armchair diagnose your problem. Make sure it is an ignition problem, and not something such as a sticky valve, etc.
I hear you there. I have to do quite a bit of that in my business. I'm pretty sure its ignition related due to the fact that the timing light strobe falters in sync with the miss.
Quote:
Originally Posted by expeditionimports
#7 - Does the problem happen everytime even when cold? IE.....does it take a while to start showing up, or immediately. On overvoltage problems we see the coil work fine when cold, but after running a while it may start missing...usually occurs right before complete failure. Rule out voltage issues immediately as if the coil fails, it WILL likely take out the Ignitor immediately.
It does it right from cold. I'll check the voltage first when I start on it today
Quote:
Originally Posted by expeditionimports
Everyone has their opinion on the kit. Considering that the conversions have been on the markets for over 8 years, with a combined "test group" of well over 1500 installations...the kits are definitely a proven upgrade. However, it is not a silver bullet and is only going to work as well as the rest of the system.
You have some homework, report back and let us know the answers to the above.
I really like the concept of the kit. I wanted one the second I read about it and based on what others have said, it obviously works well and I will continue on with it. It's frustrating when you make an improvement to something that is already working adequately and the improvement fails, but then again, we still don't know for sure what the problem is either.
Quote:
Originally Posted by expeditionimports
How much did you shorten the rotor for installation? When the rotor is installed what is the gap between it and the magnetic ring. My guess is the reason why your "condensor" fix seemed to work was because when you re-installed the rotor/cap it was seated down properly. I'll bet you have either not taken enough material off the rotor and therefore it is not fully seating, or you have taken too much off and it is know coming off easily....
I took off 1/8". There is a visible gap between the rotor base and the mag ring. The rotor snaps on very securely and is still securely fastened when I remove the cap, ie you have to pull on it a bit to pop it off. I don't think the problem lies here.
Scott, thanks for the checklist. I'll report back with voltage and a check on the other cylinders.
I checked the other cylinders, the miss corresponds to a faltering timing light for all of them.
I checked the input voltage to the ballast resistor. 28.4V which I think is normal.
The output voltage from the ballast resistor however seems to be high.
25.2 Volts. I think this should be between 17 - 21 volts. I remember 18.9 at installation of the kit. All of these checks were done at 2800 rpm.
I assume this means I need a new ballast? It still gets hot but it's obviously not reducing the voltage enough. Does this also mean that the coil is wrecked?
I won't run it any further until I get this resolved to avoid possible damage to the ignitor.
So to summarize:
-Input voltage of 28.4 seems normal.
-Output voltage from the ballast is 25.2 which is way too high.
-Do I need a new ballast or is there a way to fix or substitute it?
-Is the coil ruined and is there a way to determine this?
Scott, let me know what you think. I'll order the appropriate parts from you as soon as I get your input.
This sure sounds like a voltage breakdown in some of the secondary wiring (spark wires) of the system from the higher voltage achieved by the Pertronix ignition upgrade. If you are getting spark at all, the Pertronix is good.
Scott has been a real sport to jump in to help with this problem. IMHO, when the first part of the thread says "Everything worked great for about a month", that lets Scott completely off the hook for being responsible for this problem. Just the heading of this thread points fingers at Scott and that's not fair. If you took an electronic part back to Pep Boys, told them it worked for a month, and wanted them to fix some new problem, they'd snicker and show you the door, or sell you another part.
Sometimes a rethink of the problem will help, and an understanding of the system would really help you. To jump the Pertronix power source around to different places in 'hope' of fixing the problem is scary. The installation says to use a solid 28 vdc source, and that means to avoid the ballast entirely.
Think about the voltage at the output of the ballast. The reason the voltage varies from 28 vdc (or whatever generator output voltage is) is because the Pertronix switches in the coil's primary winding in series with the ballast, drawing current, and current flowing through a resistor (the ballast) causes a voltage drop across it. Every time a spark is generated, the voltage at the ballast drops. The reason the voltage "looks" like 17-18 volts is because it's a series of spikes and the voltmeter does it's best to average those spikes. The 'apparent' average voltage will vary with the meter used.
Hooking the Pertronix to either end of the ballast is asking for trouble. Think about it, when the Pertronix fires (conducts) the voltage at the ballast drops considerably. If the Pertronix is getting power there, then it's source voltage drops. Not exactly easy for the Pertronix to operate under those spiky voltage source conditions.
You should pick up 24vdc from the main source, like the B+ terminal on the voltage regulator. Install a relay to provide key-switching of that voltage source. (The relay should turn on when the key is activated.) FYI, there are key switched wires to several of the fuses along the front of the firewall.
If you think your ballast is bad, you can check your ballast with an Ohmmeter. It's just a resistor.
...Scott has been a real sport to jump in to help with this problem. IMHO, when the first part of the thread says "Everything worked great for about a month", that lets Scott completely off the hook for being responsible for this problem. Just the heading of this thread points fingers at Scott and that's not fair. If you took an electronic part back to Pep Boys, told them it worked for a month, and wanted them to fix some new problem, they'd snicker and show you the door, or sell you another part....
It's a rather interesting dynamic on what people percieve when they read stuff. Why I hated some of my Lit. classes in college. Some professor telling me "what the author meant". Like how the heck do you know what the author meant, the dudes been dead for 100 years so I know you didnt ask him.
Anyyyyway... I didnt read the Scott call out the same way you did at all. Just sounded to me like.... "HELLLLPPPPP Scott your the man and I'm so frustrated.... what do you think is wrong?"
This sure sounds like a voltage breakdown in some of the secondary wiring (spark wires) of the system from the higher voltage achieved by the Pertronix ignition upgrade. If you are getting spark at all, the Pertronix is good.
Well they're all new too. I got the whole kit.
Quote:
Originally Posted by hammogger
Scott has been a real sport to jump in to help with this problem. IMHO, when the first part of the thread says "Everything worked great for about a month", that lets Scott completely off the hook for being responsible for this problem. Just the heading of this thread points fingers at Scott and that's not fair. If you took an electronic part back to Pep Boys, told them it worked for a month, and wanted them to fix some new problem, they'd snicker and show you the door, or sell you another part.
You misunderstand, I'm certainly not blaming Scott or expecting him to give me free stuff. I simply know that he knows the products he sells and as a customer I'm asking him for help. I've seen him give good advice on this forum before and he's already given me some too. I thought it might serve to help others as well since a lot of the stuff on here about the pertronix upgrade is sketchy and conflicting. Again, I'm not trying to point a finger at Scott at all.
Quote:
Originally Posted by hammogger
Sometimes a rethink of the problem will help, and an understanding of the system would really help you. To jump the Pertronix power source around to different places in 'hope' of fixing the problem is scary. The installation says to use a solid 28 vdc source, and that means to avoid the ballast entirely.
Scott's instructions say to connect power source to the input at the noise suppressor which reads the same voltage as the output of the ballast. The pertronix instructions say it may also be connected at the coil. Some others, like yourself say to connect it 28V. The ignitor box says it has an operating voltage of 8v to 16v. See what I mean about conflicting information here? I'm pretty sure that Scott does not recommend running the ignitor at 28v but I may be wrong. There's nothing scary about connecting the damn thing in two of the three places that many different people have used it successfully is there? I haven't tried a solid 28v source yet.
Quote:
Originally Posted by hammogger
Think about the voltage at the output of the ballast. The reason the voltage varies from 28 vdc (or whatever generator output voltage is) is because the Pertronix switches in the coil's primary winding in series with the ballast, drawing current, and current flowing through a resistor (the ballast) causes a voltage drop across it. Every time a spark is generated, the voltage at the ballast drops. The reason the voltage "looks" like 17-18 volts is because it's a series of spikes and the voltmeter does it's best to average those spikes. The 'apparent' average voltage will vary with the meter used.
Well, that does seem to make sense.
Quote:
Originally Posted by hammogger
Hooking the Pertronix to either end of the ballast is asking for trouble. Think about it, when the Pertronix fires (conducts) the voltage at the ballast drops considerably. If the Pertronix is getting power there, then it's source voltage drops. Not exactly easy for the Pertronix to operate under those spiky voltage source conditions.
That make sense too but the instructions don't agree with you.
Quote:
Originally Posted by hammogger
You should pick up 24vdc from the main source, like the B+ terminal on the voltage regulator. Install a relay to provide key-switching of that voltage source. (The relay should turn on when the key is activated.) FYI, there are key switched wires to several of the fuses along the front of the firewall.
None of this is recommended by Pertronix or Scott that I have seen. Mine has breakers.
Quote:
Originally Posted by hammogger
If you think your ballast is bad, you can check your ballast with an Ohmmeter. It's just a resistor.
Yes, I will. Any idea what the resistance should be?
It's a rather interesting dynamic on what people percieve when they read stuff. Why I hated some of my Lit. classes in college. Some professor telling me "what the author meant". Like how the heck do you know what the author meant, the dudes been dead for 100 years so I know you didnt ask him.
Anyyyyway... I didnt read the Scott call out the same way you did at all. Just sounded to me like.... "HELLLLPPPPP Scott your the man and I'm so frustrated.... what do you think is wrong?"
Coachgeo, that is in fact exactly the way I meant it. I guess it does kind of look like I might be taking Scott and EE to task but that is certainly not what I intended. I was just trying to get answers as fast as possible to maybe solve this problem by the weekend.
As a customer I have a right to ask the seller questions, maybe not on a public forum in front of everyone though. I just thought the info would be useful.
This +24V +12V conflict regarding the Pertronix ignitor is something I'd like to understand. I've known for a while that there were two schools of thought on that, but didn't understand why.
Quote:
Originally Posted by Two Tone
Scott's instructions say to connect power source to the input at the noise suppressor which reads the same voltage as the output of the ballast. The Pertronix instructions say it may also be connected at the coil. Some others, like yourself say to connect it 28V. The ignitor box says it has an operating voltage of 8v to 16v. See what I mean about conflicting information here? I'm pretty sure that Scott does not recommend running the ignitor at 28v but I may be wrong.
I dug up my ignitor box and instructions and checked them. The instructions clearly say to connect the red lead to +24V and, if using a ballast resistor, to connect it before the resistor. The box didn't have any voltage values on it. Is it possible there are two variations of the Pertronix UM-161 out there? That would also explain why Scott recommends connecting it to +12V and Pertronix says use +24. I've bought a bit of stuff from EI over the years and gotten a fair amount of info from Scott. His advice has always proven to be correct (other than this ignitor thing).
Hammogger's explanation of voltage fluctuations between the coil and resistor fits with my understanding of how things work.
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