No Spark -- Trying to learn why
Oct 31, 2011 | 09:57 PM
#1
No Spark -- Trying to learn why
Followed the CDI test with MM as Lynn suggested with the following results.
Continuity test
AC Ignition power pin to Ground Pin ... Nothing .. Open loop
Resistance of the Timing/trigger pin to Grond Pin 150.3
AC Ignition Power Pin to frond pin while cranking 7.9 VAC
Timing Trigger to ground while cranking .08
On the output side:
resistance of Ignition Coil pin to ground pin .3
iginition coil pin to ground (CDI plugged in) while cranking: goes to 50 -51 volts
Followed your tutorial step by step Lynn, With the Kill pin pulled from plug there was no spark.
Trying to learn how to diagnose these little machines. Does this look as though the stator is the problem?
Continuity test
AC Ignition power pin to Ground Pin ... Nothing .. Open loop
Resistance of the Timing/trigger pin to Grond Pin 150.3
AC Ignition Power Pin to frond pin while cranking 7.9 VAC
Timing Trigger to ground while cranking .08
On the output side:
resistance of Ignition Coil pin to ground pin .3
iginition coil pin to ground (CDI plugged in) while cranking: goes to 50 -51 volts
Followed your tutorial step by step Lynn, With the Kill pin pulled from plug there was no spark.
Trying to learn how to diagnose these little machines. Does this look as though the stator is the problem?
Oct 31, 2011 | 10:10 PM
#2
No Spark -- Trying to learn why
Followed the CDI test with MM as Lynn suggested with the following results.
Continuity test
AC Ignition power pin to Ground Pin ... Nothing .. Open loop
Resistance of the Timing/trigger pin to Grond Pin 150.3
AC Ignition Power Pin to frond pin while cranking 7.9 VAC
Timing Trigger to ground while cranking .08
On the output side:
resistance of Ignition Coil pin to ground pin .3
Maybe I'm wrong but looks like not enough voltage getting to the CDI to trigger a spark?
iginition coil pin to ground (CDI plugged in) while cranking: goes to 50 -51 volts
Followed your tutorial step by step Lynn, With the Kill pin pulled from plug there was no spark.
Trying to learn how to diagnose these little machines. Does this look as though the stator is the problem?
Continuity test
AC Ignition power pin to Ground Pin ... Nothing .. Open loop
Resistance of the Timing/trigger pin to Grond Pin 150.3
AC Ignition Power Pin to frond pin while cranking 7.9 VAC
Timing Trigger to ground while cranking .08
On the output side:
resistance of Ignition Coil pin to ground pin .3
Maybe I'm wrong but looks like not enough voltage getting to the CDI to trigger a spark?
iginition coil pin to ground (CDI plugged in) while cranking: goes to 50 -51 volts
Followed your tutorial step by step Lynn, With the Kill pin pulled from plug there was no spark.
Trying to learn how to diagnose these little machines. Does this look as though the stator is the problem?
Oct 31, 2011 | 11:42 PM
#3
Electrical Expert
Likes High Voltage In The Tub!
Likes High Voltage In The Tub!
Joined: Dec 2008
Posts: 3,260
Likes: 14
From: Tracy, California, USA
There is some conflicting info to wade through... 
Do you know whether or not you have an AC powered CDI or a DC powered CDI? Is this a five pin CDI, a four pin CDI, or a six pin CDI (2 pin and 4 pin)? If you've mentioned this previously I apologize - often times different threads get sort of stirred together in my mind...
If you really have an AC powered CDI then your power voltages and resistances are wrong. But you also report AC voltage (50 volts!) at the output of the CDI which cannot be if your CDI has no power going to it.
And your trigger voltage is too low to even make an output from the CDI even if it did have power... This does not make sense...
The first thing to do is determine if your CDI is DC powered or AC powered. How many pins on your CDI?
Do you know whether or not you have an AC powered CDI or a DC powered CDI? Is this a five pin CDI, a four pin CDI, or a six pin CDI (2 pin and 4 pin)? If you've mentioned this previously I apologize - often times different threads get sort of stirred together in my mind...
If you really have an AC powered CDI then your power voltages and resistances are wrong. But you also report AC voltage (50 volts!) at the output of the CDI which cannot be if your CDI has no power going to it.
And your trigger voltage is too low to even make an output from the CDI even if it did have power... This does not make sense...
The first thing to do is determine if your CDI is DC powered or AC powered. How many pins on your CDI?
Followed the CDI test with MM as Lynn suggested with the following results.
Continuity test
AC Ignition power pin to Ground Pin ... Nothing .. Open loop
Resistance of the Timing/trigger pin to Grond Pin 150.3
AC Ignition Power Pin to frond pin while cranking 7.9 VAC
Timing Trigger to ground while cranking .08
On the output side:
resistance of Ignition Coil pin to ground pin .3
Maybe I'm wrong but looks like not enough voltage getting to the CDI to trigger a spark?
iginition coil pin to ground (CDI plugged in) while cranking: goes to 50 -51 volts
Followed your tutorial step by step Lynn, With the Kill pin pulled from plug there was no spark.
Trying to learn how to diagnose these little machines. Does this look as though the stator is the problem?
Continuity test
AC Ignition power pin to Ground Pin ... Nothing .. Open loop
Resistance of the Timing/trigger pin to Grond Pin 150.3
AC Ignition Power Pin to frond pin while cranking 7.9 VAC
Timing Trigger to ground while cranking .08
On the output side:
resistance of Ignition Coil pin to ground pin .3
Maybe I'm wrong but looks like not enough voltage getting to the CDI to trigger a spark?
iginition coil pin to ground (CDI plugged in) while cranking: goes to 50 -51 volts
Followed your tutorial step by step Lynn, With the Kill pin pulled from plug there was no spark.
Trying to learn how to diagnose these little machines. Does this look as though the stator is the problem?
Nov 1, 2011 | 12:23 AM
#4
It's just like this one and checks as AC. It is a 5 pin CDI.
Seems goofy to me too. But I checked it 4-5 times thinking I did not know how to operate a mulitmeter. I have to "Select" the range by cursoring thru until I get the digits. For AC that gives me 3 digits and one decimal place on this meter. I stick it in a house plug and get accurate readings to one decimal place.
So I don't really know what scale it's on (you said to set the meter on 100 volt scale) So that's the closest I can come to what you wanted.
With the meter set like that, the CDI Unplugged The voltage from the AC Ignition Power pin to the ground pin while cranking the engine shows 7.9 volts.
I cant set the meter to 20 volts for the next test, it is in the same condition as above. ..... With the CDI plugged in, measuring from the Ignition coil pin to ground while cranking the engine I get 50 to 51 volts.
I have done this maybe 10 -15 times as I have been fooling with it all day on and off. I went by your instructional step by step and these are the readings of this I am positive.
Any discrepancy in the accuracy of my readings might be in the scale but I assure you I have checked, double checked and then checked again.
The meter is a cen-tech P98674. On the volts part it is suppose to automatically detect AC or DC and read a proper range. I can over ride that feature and select either AC or DC digitally and then set the range. I am not that familiar with this meter, but it seems straight forward to me, I just set the amount of prime digits and decimal places I want and it returns a value. I don't know how to set it on just 20 VAC. Maybe this is a problem I don't know. I will state again the readings may not make sense but that's what they are I can't change that. I understand what the values are suppose to be but no clue as to what it indicates when the values are something other than the desired numbers.
If you really have an AC powered CDI then your power voltages and resistances are wrong. But you also report AC voltage (50 volts!) at the output of the CDI which cannot be if your CDI has no power going to it.
So I don't really know what scale it's on (you said to set the meter on 100 volt scale) So that's the closest I can come to what you wanted.
With the meter set like that, the CDI Unplugged The voltage from the AC Ignition Power pin to the ground pin while cranking the engine shows 7.9 volts.
I cant set the meter to 20 volts for the next test, it is in the same condition as above. ..... With the CDI plugged in, measuring from the Ignition coil pin to ground while cranking the engine I get 50 to 51 volts.
I have done this maybe 10 -15 times as I have been fooling with it all day on and off. I went by your instructional step by step and these are the readings of this I am positive.
Any discrepancy in the accuracy of my readings might be in the scale but I assure you I have checked, double checked and then checked again.
The meter is a cen-tech P98674. On the volts part it is suppose to automatically detect AC or DC and read a proper range. I can over ride that feature and select either AC or DC digitally and then set the range. I am not that familiar with this meter, but it seems straight forward to me, I just set the amount of prime digits and decimal places I want and it returns a value. I don't know how to set it on just 20 VAC. Maybe this is a problem I don't know. I will state again the readings may not make sense but that's what they are I can't change that. I understand what the values are suppose to be but no clue as to what it indicates when the values are something other than the desired numbers.
Nov 3, 2011 | 11:47 PM
#6
Electrical Expert
Likes High Voltage In The Tub!
Likes High Voltage In The Tub!
Joined: Dec 2008
Posts: 3,260
Likes: 14
From: Tracy, California, USA
My comments in blue...
It's just like this one and checks as AC. It is a 5 pin CDI.
[I would call the following picture a six pin CDI (two pin and four pin connectors)]
Seems goofy to me too. But I checked it 4-5 times thinking I did not know how to operate a mulitmeter. I have to "Select" the range by cursoring thru until I get the digits. For AC that gives me 3 digits and one decimal place on this meter. I stick it in a house plug and get accurate readings to one decimal place.
So I don't really know what scale it's on (you said to set the meter on 100 volt scale) So that's the closest I can come to what you wanted. [Your meter is probably autoranging. It adjusts the scale automatically for maximum resolution. This is a good thing, since many electrical novices (for example) tell they measure 0 ohms for the ignition coil resistance where the proper number is 0.3 ohms - yet they are on the 1 Megaohm scale, where one least significant change is 10,000 ohms. It is like someone trying to measure the weight of a postal letter on a highway truck scale.
But all autoranging meters also put out some sort of display indicator saying what the displayed digits mean. Look for little text icons like volts (V), millivolt (mV), ohms, KOhms (kilo ohms), MOhms (mega ohms). The word ohms is often represented with the greek letter omega, which look like an upside down horseshoe]
With the meter set like that, the CDI Unplugged The voltage from the AC Ignition Power pin to the ground pin while cranking the engine shows 7.9 volts.
I cant set the meter to 20 volts for the next test, it is in the same condition as above. ..... With the CDI plugged in, measuring from the Ignition coil pin to ground while cranking the engine I get 50 to 51 volts. [The above two statements make no sense to me no matter how I look at it. Your meter is different from the norm, which is possible since we're asking the meter to measure weird shaped waveforms which they really aren't designed to do. But still it makes no sense. Roughly 8 volts AC in giving 51 volts AC out? This makes no sense.
Do you have access to another meter? Centech isn't known for being very reliable, or being an industry leader
]
I have done this maybe 10 -15 times as I have been fooling with it all day on and off. I went by your instructional step by step and these are the readings of this I am positive.
Any discrepancy in the accuracy of my readings might be in the scale but I assure you I have checked, double checked and then checked again.
The meter is a cen-tech P98674. [I did a google search on this meter to find a manual. Strangely at the top of the google list was a couple sites that displayed lots of images that had nothing to do with meters. I got distracted...] On the volts part it is suppose to automatically detect AC or DC and read a proper range. [But you should have some indication on the meter beside the digits that says what it is measuring (AC or DC, and what scale)] I can over ride that feature and select either AC or DC digitally and then set the range. I am not that familiar with this meter, but it seems straight forward to me, I just set the amount of prime digits and decimal places I want and it returns a value. I don't know how to set it on just 20 VAC. Maybe this is a problem I don't know. I will state again the readings may not make sense but that's what they are I can't change that. I understand what the values are suppose to be but no clue as to what it indicates when the values are something other than the desired numbers.
[I would call the following picture a six pin CDI (two pin and four pin connectors)]
Seems goofy to me too. But I checked it 4-5 times thinking I did not know how to operate a mulitmeter. I have to "Select" the range by cursoring thru until I get the digits. For AC that gives me 3 digits and one decimal place on this meter. I stick it in a house plug and get accurate readings to one decimal place.
So I don't really know what scale it's on (you said to set the meter on 100 volt scale) So that's the closest I can come to what you wanted. [Your meter is probably autoranging. It adjusts the scale automatically for maximum resolution. This is a good thing, since many electrical novices (for example) tell they measure 0 ohms for the ignition coil resistance where the proper number is 0.3 ohms - yet they are on the 1 Megaohm scale, where one least significant change is 10,000 ohms. It is like someone trying to measure the weight of a postal letter on a highway truck scale.
But all autoranging meters also put out some sort of display indicator saying what the displayed digits mean. Look for little text icons like volts (V), millivolt (mV), ohms, KOhms (kilo ohms), MOhms (mega ohms). The word ohms is often represented with the greek letter omega, which look like an upside down horseshoe]
With the meter set like that, the CDI Unplugged The voltage from the AC Ignition Power pin to the ground pin while cranking the engine shows 7.9 volts.
I cant set the meter to 20 volts for the next test, it is in the same condition as above. ..... With the CDI plugged in, measuring from the Ignition coil pin to ground while cranking the engine I get 50 to 51 volts. [The above two statements make no sense to me no matter how I look at it. Your meter is different from the norm, which is possible since we're asking the meter to measure weird shaped waveforms which they really aren't designed to do. But still it makes no sense. Roughly 8 volts AC in giving 51 volts AC out? This makes no sense.
Do you have access to another meter? Centech isn't known for being very reliable, or being an industry leader
]I have done this maybe 10 -15 times as I have been fooling with it all day on and off. I went by your instructional step by step and these are the readings of this I am positive.
Any discrepancy in the accuracy of my readings might be in the scale but I assure you I have checked, double checked and then checked again.
The meter is a cen-tech P98674. [I did a google search on this meter to find a manual. Strangely at the top of the google list was a couple sites that displayed lots of images that had nothing to do with meters. I got distracted...] On the volts part it is suppose to automatically detect AC or DC and read a proper range. [But you should have some indication on the meter beside the digits that says what it is measuring (AC or DC, and what scale)] I can over ride that feature and select either AC or DC digitally and then set the range. I am not that familiar with this meter, but it seems straight forward to me, I just set the amount of prime digits and decimal places I want and it returns a value. I don't know how to set it on just 20 VAC. Maybe this is a problem I don't know. I will state again the readings may not make sense but that's what they are I can't change that. I understand what the values are suppose to be but no clue as to what it indicates when the values are something other than the desired numbers.
Nov 4, 2011 | 01:26 AM
#7
Lynn, that meter in the AC mode can display 400 mV, 4 volts, 40 volts and 400 volts. I took the readings manually setting it to the 400 volt range because the expected voltage on the crank was over 40 and my next range is 400.
Here's the manual. http://manuals.harborfreight.com/man...8999/98674.pdf
OK it's a 5 wire, stator going into a 6 pin CDI (4 and 2) I surrender.
Resistance choices are:
400Ω 4kΩ 40kΩ 400k( 4M( 40M(
There is a single position on the dial selector for ohms, capacitance etc and the icon I used was the Ω and I assume that starts at 400Ω. Each touch of the range button cursors through all the ranges. All resistance was checked on the same scale. (I think)
I should have a new stator tomorrow and will somehow get to the bottom of this. The previous owner has replaced the CDI, Coil, Regulator and solenoid. He gave up when he couldn't get to the stator. (needed a decent tool to remove the flywheel). I have another 49 cc engine that the stator will fit so even if that's not the problem I can have a spare one sitting on the shelf, no loss as it will likely be used at some point. I just want to learn cold what to expect value wise and if something is out of parameters what is likely the cause. Kinda like detective work eh.
I need to make a worksheet with all the test on it and the required numbers along with a blank space to record the actual readings. That might eliminate some of the confusion because with taking a bunch of readings it is easy for a novice such as myself to get crossed up.
Here's the manual. http://manuals.harborfreight.com/man...8999/98674.pdf
OK it's a 5 wire, stator going into a 6 pin CDI (4 and 2) I surrender.
Resistance choices are:
400Ω 4kΩ 40kΩ 400k( 4M( 40M(
There is a single position on the dial selector for ohms, capacitance etc and the icon I used was the Ω and I assume that starts at 400Ω. Each touch of the range button cursors through all the ranges. All resistance was checked on the same scale. (I think)
I should have a new stator tomorrow and will somehow get to the bottom of this. The previous owner has replaced the CDI, Coil, Regulator and solenoid. He gave up when he couldn't get to the stator. (needed a decent tool to remove the flywheel). I have another 49 cc engine that the stator will fit so even if that's not the problem I can have a spare one sitting on the shelf, no loss as it will likely be used at some point. I just want to learn cold what to expect value wise and if something is out of parameters what is likely the cause. Kinda like detective work eh.
I need to make a worksheet with all the test on it and the required numbers along with a blank space to record the actual readings. That might eliminate some of the confusion because with taking a bunch of readings it is easy for a novice such as myself to get crossed up.
Trending Topics
Thread
Thread Starter
Forum
Replies
Last Post
KingDingalling
Introduce Yourself
3
Jul 29, 2015 10:55 AM
5pinadjustablecdi, ac, cdi, centech, coil, electrical, igniton, manual, ohms, p98674, pin, power, resistance, vega, volts
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)