Talking through an ignition problem

[trig123]

Originally Posted by Cartmaster

Nice one Trig. As you can guess, I got bored today LOL.

Will wait on you before loading you with more research.

Post away Cartmaster. I always like new info.

[trig123]

Wake up Cartmaster. I need help
This might be coming to an end soon lol
Got donated a new ford module still in box today
The mechanic I worked with at the golf course many years ago showed up today bringing me this blue tab thing He helped me because it was interesting to him also.
Module wires are connected like this >
Red to plus side of coil
Green to negative side of coil
Orange to red pulser wire
Purple to black pulser wire
White to small hot terminal on solenoid
Black to ground
We put the ballast resistor just before plus side of coil
It started and I got 8.75 volts at positive side of coil. It ran good with stock coil and I was happy. We both thought this was the fix but more to come

I turned it off after running it for 10 smokey minutes
It wouldn't start back. It fired the one time with my sparky tester when I turned off the switch I am using. Same thing as putting a jump wire from battery to small terminal.
I put the Denso coil back on it and away it went. I then checked voltage at + side of this Denso and I was getting 11.75 volts. Where in the world did the 8.75 go
The module has got to be changing the voltage because the red wire from module is connected to coil.
I put a used aftermarket ezgo coil on it and again it started but it got hot. I checked voltage and again it was almost 12 volts at coil. I shut it off and it wouldn't crank back.
Again I stuck the Denso back on it and of course it started again but this time the voltage at + side was at 8.75 again.
I think this has something to do with the start circuit and run circuit like on a Ford truck. These carts don't have that.
Just when I got excited that finally things were going to work it went backward again.

[CP241]

I wonder if you’ve maybe caused minor damage to the coil causing the intermittent one spark event once it gets hot? If you swapped to the other coils and it worked…

[trig123]

Originally Posted by CP241

I wonder if you’ve maybe caused minor damage to the coil causing the intermittent one spark event once it gets hot? If you swapped to the other coils and it worked…

We both thought I may have trashed the coil but it worked later on . I ran the engine 15 minutes using it. Cut it off and no start. Confused. Yes
I am sort of afraid to try any more coils though. These OEM coils are rare.
The ohms show the coil I was using is good but really I have never put much trust in checking a coil with a meter.
I plan on sticking it on my cart tomorrow and see how it runs. I hope I haven't trashed it. I really don't know where I got this OEM coil. It might have been defective to begin with.
It could be the lower voltage it sometimes has won't fire it. Denso comes to the rescue but I may be on the way to toasting it
Tomorrow I am not even looking at this smokey engine. I got wires coming from the ceiling

[Cartmaster]

I need to see this on a big screen against the diagram. Does the coil at any point see battery voltage or is the ballast the only connection at the coil + terminal? If the coil see's full 12v or more it may well get hot. Let me ponder this once I am at my computer. I can visualise better once I am fully awake with my glasses on lol 😆

[trig123]

Originally Posted by Cartmaster

I need to see this on a big screen against the diagram. Does the coil at any point see battery voltage or is the ballast the only connection at the coil + terminal? If the coil seems full 12v or more it may well get hot. Let me ponder this once I am at my computer. I can visualise better once I am fully awake with my glasses on lol 😆

The voltage changes at the coil + . The ballast is the only thing I have between it.
I may have this module wired wrong but when it runs good when its running. Starts fast and opens up great. But things then head downhill fast lol
Ponder all you need Cartmaster. That smokey is not going anywhere unless I turn the table over

[Cartmaster]

At first glance it seems the voltage change at the coil is suspect. The only way you should see the raised voltage after the ballast is a faulty resister or a raised voltage before the ballast but at first you had just under 9v as expected. I am confused. I will log back on when I get to my office and have a think.

EDIT.
I assume you have the SG connected up to charge battery! I don't suppose the VR has failed and applying higher volts to the circuit?

[trig123]

Originally Posted by Cartmaster

At first glance it seems the voltage change at the coil is suspect. The only way you should see the raised voltage after the ballast is a faulty resister or a raised voltage before the ballast but at first you had just under 9v as expected. I am confused. I will log back on when I get to my office and have a think.

EDIT.
I assume you have the SG connected up to charge battery! I don't suppose the VR has failed and applying higher volts to the circuit?

Starter/Generator is connected to a good battery. V/R tests good, shuts back at 14.5 volts. The red wire coming out of module is where I think it is changing. This setup is just like one in a cart except I used a ezgo key switch to turn it off and on. Maybe tomorrow will be better and I can give you better info. Its late here and I got to get to bed. Check back with you then. Tom

[Cartmaster]

Have a good night Trig. I managed to sleep through last night for a change!

This may be a long and disjointed post as i will probably be adding stuff as i think more during the day and writing down my thoughts as i go. I may try to summarize at the end if i can.

EDIT. It may be worth reading the edit at the end of this post first. It may make you feel a bit better LOL.

I was thinking about this while driving to work. First thing i note is the fact that you have the white wire connected in. This is designed to be used only when cranking for start on a car/truck to allow the starter to spin easily by retarding the ignition. The way you have it connected, it is telling the module to retard ignition by 4 degrees all the time. This may or may not be the issue with no restart on a warm engine. I would disconnect it before doing any other tests. Let the module run as it should as we do not have a keyswitch/solenoid that disengages the starter and hence the white wire once the engine is running. This should allow the engine to run at whatever timing the pulser is telling the module to do. Several versions of these modules were available with different degrees of retard. One in particular retarded ignition by 14 degrees and general consensus is that these were for low compression engines such as Turbo'd.

So lets ignore the white wire and remove it and tape it off. If you have no tape use a wire nut

Double check all your wiring next, to make sure you have all good connections for power and ground. Your statement about a single spark when removing power from the coil should remind us of problems in this dept under normal diagnosis on the carts. What I think this is telling us is that the coil is energized but still seeing a connection through ground ( somehow ) and only dropping out and producing a spark when removing the supply. This usually would be done via points opening or the module opening ground.

I know on your first attempt with setting up the engine on the GM module, you found wiring issues and corrected them. one being a broken wire and another issue i cant recall at the moment.

Double check the modified diagram i have posted below against your wiring , ignore the white wire and any previous diagrams. This one should be similar to yours but without the ballast overide and white wire connected.

If you are getting close to supply voltage after the ballast at +ve coil connection, there is something wrong here. I believe we have discovered that the OEM setup appears to supply around 10/11 volts at the coil when running, so this raised voltage may be why the OEM coil was getting hot.

I also note your comment about start and run voltages on old trucks being different but this was usually done by bypassing the ballast either from the solenoid or key switch, not the ignition modules. A quick google search shows nothing about these modules changing the voltage for start and run, but who knows? If it does, it should change between low and high volts for the correct coil type without the need for a ballast.

The voltage change after the ballast is what confuses me. As i said earlier this morning, I cant see anything causing this other than a failed ballast or it getting extremely hot and changing resistance ( but i thought resistance increased with heat ) or the input to the ballast rising way above supply voltage, but I cannot see that happening either as again, I would expect the resistor would get hotter than normal.

So, from your description, I can safely assume that the only connection to the coil + is directly from the output side of the ballast? Nothing else such as the bypass wire on your diagram.

Why are we seeing just under 12 volts after the ballast and where is it coming from? and why does it seem to change from the expected nominal 9 volts you saw previously?

Is this with the engine running, not running or both?

Do you have two volt meters, to place one before and one after the ballast to monitor what is happening?

Is it worth checking a known good working cart to see what the voltage at the coil is, running and not running to compare?

I am also assuming you are monitoring spark all time, or was it just when the engine would not re start?

How about also reading the negative side of the coil to see if you get a constant regular switch signal from the pulser and module while cranking and running, and seeing if this signal is not present when it will not restart or die. This should tell you if it is the module/pulser to suspect being faulty or the coil.

I think under these circumstances, I would be tempted to undo everything and start again. But that is just me and the way I work.

If you sit and think about it, The only difference we have here is between the way it is set up in a car, with the solenoid being for crank start only, unlike the solenoid and starter/generator on a cart being energized all the while the engine is running. This is why I think the power to the coil and module should ideally come from the switched large hot terminal of the solenoid. Plenty of current is available and it is not affected by excessive draw from the vehicle wiring apart from the starter generator. If we suspect the S/G is affecting things, we can try another way to feed the coil and module.

I have simplified the diagram to check against your wiring. It does away with the solenoid and ballast overide and also ignores the white wire. If your wiring matches this, then i do not see how the coil sees more than 9 volts unless it is as you say, coming from the module at greater than expected voltage for a 12 volt car electrical system that usually see's around 14.5v maximum. Unless the Ballast is not doing its job in reducing the voltage.



If anyone can see a flaw in my thinking please Make a comment.

I just wish I could be there Trig, Being thousands of miles away is not helping me here!

Summary.

1, It appears that the OEM coil does not like full battery voltage to run but the Denso seems good at around 12/14 volts.

2, The white wire should be ignored at this stage as all it does is retard ignition by four degrees when supplied source voltage.

3, Wiring should be double checked to confirm it is as in the last diagram I have simplified

4, See if we can tidy up the wiring on the test rig to eliminate any errors.

5, Once all is confirmed and reconnected, Disconnect starter at this stage while testing voltages! confirm voltage after ballast is around 9 volts with Ignition supply on and full 12/14 volts is supplied at red on module plus before ballast.

6, Confirm good grounds where needed.

7, Re connect starter to turn engine over with plug leads grounded and check voltages again at each side of the ballast before going any further.

8, If all seems well, see if we can confirm regular pulses from pick up and also from igniter module. Monitor ballast/coil voltages too if possible while turning engine over.

9, If these tests go well, maybe run the engine at a medium idle and test all these points again to see if anything changes such as the ballast input and output voltages.

10, If all looks good, run the engine for a longer period of time, maybe occasionally switching off and attempting to restart to see where we are at.

Then we can work out what the next move should be.

I understand you wanting to be done with this Trig, and would fully understand if you have had enough. But like me, you dont want it to beat you .

EDIT

I may be wrong here, but it seems that with the Denso coil it is running fine with the higher voltage from the Module, albeit strange that the ballast ought to be lowering this to around 9volts. So maybe CP's comment is valid regarding the OEM coil breaking down.

If you recall, I spoke previously of back in the day, about burning out coils by permanently bypassing the ballast for "better" performance with a fatter spark. Well, you may also recall, the cure was to either reinstate the ballast, or fit a 12Volt coil. So maybe you have unknowingly cracked this project. Maybe the OEM coils do not like the full voltage but the Denso does, as it may be rated for 12V operation. We should be able to check this if you have a part number for it. If this is the case, sourcing a 12 coil that works with the "Duraspark" module, Is all that is needed to make this sucker run fine. Then it is a case of trying it on just the red wire from the module to see if the timing is good. That just leaves the pulser to find non OEM, but I reckon the Amazon ones will be fine if you find one that works.

I have read more today about older car conversions being retrofitted with these modules and it seems some people switch the white wire to change from cruising to high performance running. so it looks as if need be we can run on the white wire if we need the retarded 4 degrees to run nicely.

I could be wrong as I already said

I still wonder what the difference in timing is with the MCI. Maybe another project if i can find one over here! If the duraspark timing can be altered by swapping white and red, maybe we have a module that would run both types or is that just very wishful thinking

[trig123]

Originally Posted by Cartmaster

Have a good night Trig. I managed to sleep through last night for a change!

This may be a long and disjointed post as i will probably be adding stuff as i think more during the day and writing down my thoughts as i go. I may try to summarize at the end if i can.

I was thinking about this while driving to work. First thing i note is the fact that you have the white wire connected in. This is designed to be used only when cranking for start on a car/truck to allow the starter to spin easily by retarding the ignition. The way you have it connected, it is telling the module to retard ignition by 4 degrees all the time. This may or may not be the issue with no restart on a warm engine. I would disconnect it before doing any other tests. Let the module run as it should as we do not have a keyswitch/solenoid that disengages the starter and hence the white wire once the engine is running. This should allow the engine to run at whatever timing the pulser is telling the module to do. Several versions of these modules were available with different degrees of retard. One in particular retarded ignition by 14 degrees and general consensus is that these were for low compression engines such as Turbo'd.

So lets ignore the white wire and remove it and tape it off. If you have no tape use a wire nut

Double check all your wiring next, to make sure you have all good connections for power and ground. Your statement about a single spark when removing power from the coil should remind us of problems in this dept under normal diagnosis on the carts. What I think this is telling us is that the coil is energized but still seeing a connection through ground ( somehow ) and only dropping out and producing a spark when removing the supply. This usually would be done via points opening or the module opening ground.

I know on your first attempt with setting up the engine on the GM module, you found wiring issues and corrected them. one being a broken wire and another issue i cant recall at the moment.

Double check the modified diagram i have posted below against your wiring , ignore the white wire and any previous diagrams. This one should be similar to yours but without the ballast overide and white wire connected.

If you are getting close to supply voltage after the ballast at +ve coil connection, there is something wrong here. I believe we have discovered that the OEM setup appears to supply around 10/11 volts at the coil when running, so this raised voltage may be why the OEM coil was getting hot.

I also note your comment about start and run voltages on old trucks being different but this was usually done by bypassing the ballast either from the solenoid or key switch, not the ignition modules. A quick google search shows nothing about these modules changing the voltage for start and run, but who knows? If it does, it should change between low and high volts for the correct coil type without the need for a ballast.

The voltage change after the ballast is what confuses me. As i said earlier this morning, I cant see anything causing this other than a failed ballast or it getting extremely hot and changing resistance ( but i thought resistance increased with heat ) or the input to the ballast rising way above supply voltage, but I cannot see that happening either as again, I would expect the resistor would get hotter than normal.

So, from your description, I can safely assume that the only connection to the coil + is directly from the output side of the ballast? Nothing else such as the bypass wire on your diagram.

Why are we seeing just under 12 volts after the ballast and where is it coming from? and why does it seem to change from the expected nominal 9 volts you saw previously?

Is this with the engine running, not running or both?

Do you have two volt meters, to place one before and one after the ballast to monitor what is happening?

Is it worth checking a known good working cart to see what the voltage at the coil is, running and not running to compare?

I am also assuming you are monitoring spark all time, or was it just when the engine would not re start?

How about also reading the negative side of the coil to see if you get a constant regular switch signal from the pulser and module while cranking and running, and seeing if this signal is not present when it will not restart or die. This should tell you if it is the module/pulser to suspect being faulty or the coil.

I think under these circumstances, I would be tempted to undo everything and start again. But that is just me and the way I work.

If you sit and think about it, The only difference we have here is between the way it is set up in a car, with the solenoid being for crank start only, unlike the solenoid and starter/generator on a cart being energized all the while the engine is running. This is why I think the power to the coil and module should ideally come from the switched hot of the solenoid. Plenty of current is available and it is not affected by the vehicle wiring apart from the starter generator. If we suspect the S/G is affecting things, we can try another way to feed the coil and module.

I have simplified the diagram to check against your wiring. It does away with the solenoid and ballast overide and also ignores the white wire. If your wiring matches this, then i do not see how the coil sees more than 9 volts unless it is as you say, coming from the module at greater than expected voltage for a 12 volt car electrical system that usually see's around 14.5v maximum. Unless the Ballast is not doing its job in reducing the voltage.



If anyone can see a flaw in my thinking please Make a comment.

I just wish I could be there Trig, Being thousands of miles away is not helping me here!

Summary.

1, It appears that the OEM coil does not like full battery voltage to run but the Denso seems good at around 12/14 volts.

2, The white wire should be ignored at this stage as all it does is retard ignition by four degrees when supplied source voltage.

3, Wiring should be double checked to confirm it is as in the last diagram I have simplified

4, See if we can tidy up the wiring on the test rig to eliminate any errors.

5, Once all is confirmed and reconnected, Disconnect starter at this stage while testing voltages! confirm voltage after ballast is around 9 volts with Ignition supply on and full 12/14 volts is supplied at red on module plus before ballast.

6, Confirm good grounds where needed.

7, Re connect starter to turn engine over with plug leads grounded and check voltages again at each side of the ballast before going any further.

8, If all seems well, see if we can confirm regular pulses from pick up and also from igniter module. Monitor ballast/coil voltages too if possible while turning engine over.

9, If these tests go well, maybe run the engine at a medium idle and test all these points again to see if anything changes such as the ballast input and output voltages.

10, If all looks good, run the engine for a longer period of time, maybe occasionally switching off and attempting to restart to see where we are at.

Then we can work out what the next move should be.

I understand you wanting to be done with this Trig, and would fully understand if you have had enough. But like me, you dont want it to beat you .

Good write up Cartmaster.
The S/G is suspect. It came off a cart I bought two years ago that was overcharging from defective V/R and the cart would not run above 5mph.

I was in the process if putting brushes in another one and was stopped to check on an old 2 stroke cart that wasn't charging .
I will address that today. I just don't trust this one because I know its been hot. Mark it with tape so I don't pick it up again.

S/G had stopped turning Sunday afternoon when I was at the shop messing with this module. I could tap on it and it would start again. Just like bad brushes but they are almost new. I took it apart a few weeks ago and cleaned everything up. Now its working again but first on list is get that one off.

I also do have a few meters. I will see what is going on using two.

I will remove the white wire, install another S/G , tidy up my surrounding including wire nuts and see what happens and report back .

My shop hasn't been this unorganized since I came back five years ago. This one challenge has made me forget I need to clean up and put up things.

I also have a bad habit of jumping from one thing to another. I can walk from one end of the shop to the other looking for something.

The next thing I know I am doing something else and forget what I walked to back of shop to begin with. Its getting worse as I get older ADD plus is what I would call it.

Like I have mentioned before. I have lots of visitors who want to see what old Tom is doing. Most are annoying but not all. Yesterday the people that came in I enjoyed stopping and chatting with. Therefore I didn't get much done and when I did it got more confusing.

More later. Tom