coils

[Lou]

This is interesting. So I did a search on the CY4002 part number. Found a company that has 295 of them! They purchase surplus. Interesting enough we were in their system as we've done business in the past. Out of curiosity, I asked them to quote the following quantities, hoping for some secret honey hole that wanted to sell them for $25 each. LOL - No such luck!


Part Number Qty Price Total
CY4002 295 $295.63 $87,210.85
Description: COIL
Delivery: Immediate
Condition: New Surplus
Certs: Yes

CY4002 100 $375.00 $37,500.00
Description: COIL
Delivery: Immediate
Condition: New Surplus
Certs: Yes
CY4002 50 $410.00 $20,500.00
Description: COIL
Delivery: Immediate
Condition: New Surplus
Certs: Yes

Guy

CY4002 is the wrong part number. The specs here say it is 2 inches in diameter.... wrong coil. https://www.nsn-sourcing.com/nato/rfq/p ... 71/cy4002/

[rickf]

Here is what I came up with, I don't have a coil in my hands right this minute to measure but it sure looks the same.

https://www.wbparts.com/rfq/2920-00-324-0371.html

[Lou]

Thought I would share some conversations that occurred about the “new” black coil. I called up Pete to ask him if I could return the coil and the conversation went into the technical aspects of his coil. Explained that with the primary resistance being double that of the original coil 12 Ohms Vs. 6 Ohms, there would be issues with electronic ignition modules frying.

Went on to explain that raising the resistance also raises the inductance and this increases the inductive “kick back”of the coil when the ignition module operates the coil.

You can see this for yourselves if you have a chrome coil and a nos coil. Connect the coil across a battery with alligator clips, every time you disconnect the coil you will see a small spark at the alligator clip. When the magnetic field collapses from points or a electronic ignition module opening, this induces a voltage back in the primary and secondary of the coil. You can see this effect here https://youtu.be/EKhQ5sFM-Gs?t=178

This induced voltage is higher then the electronic ignition modules were designed to take. So the end result is that the electronic ignition module shorts out, and when it does it keeps 24 volts connected to the coil (like points being closed), so you wind up with a burned out coil and ignition module, like so may of you have had occur.

Pete was aware of the video on youtube and wanted me, himself and Destin (the gentlemen that helped design the black coil) to have a video meeting. This occurred for about an hour last evening.

Pete is a great guy and was concerned about the information above and is really trying hard to produce a better coil then the chrome Chinese coil. So here are the facts I learned.

The black coil was actually designed for the M38 Jeeps with points ignition. It was not designed for electronic ignition modules as we use in our mutts. With points ignitions, the issues detailed above will not occur. So the coil will work in a mutt with points but due to the higher primary resistance, the secondary will produce less voltage, 7,000 volts less. In Pete’s defense his coil is only found in the M38 section of his web page, not the M151 section. I believe when we all saw the video he posted on Facebook, we assumed that the coil would be designed for mutts as well. Pete said he is going to add a disclaimer on his web page NOT to use the coil with electronic ignition modules. The reason the primary resistance was designed to be higher, was to prevent the coil from overheating. In fact the coil was tested with voltages up to 35 volts simulating a shorted alternator regulator.

Then the discussion shifted on how to make a coil that is the same as a nos coil with the proper primary and secondary resistances. Destin said he would be willing to open up coils with a lathe, if I send them to him, then send them back to me. This will be much better than me using a sawzall.
So we are going to try and reverse engineer a nos coil and maybe come up with a plan for a reasonable priced replacement coil. This will not happen tomorrow, because Pete would have to commit to a minimum quantity for production (at least 500 units).

So what I need from you folks is a bad chrome coil, and a bad nos coil. Then I can find out what gauge wire is inside and calculate the turns ratio. I have tried to find the original manufacturer specifications for the original mutt coils, with no luck. If any of you can find this information, it would be very helpful. As a MVPA member, do you think the MVPA archives would have this information? Have not contacted them yet. There were several manufactures that built coils, and they are all slightly different from each other (including output voltage I measured).

So maybe there is some hope on the horizon and if we work together just maybe we can come up with something workable.

[old dodge guy]

Well, I have been told that the MVPA was given 5 semi truck loads of drawings, so it is not unreasonable to assume that they could have that info. Whether they have ever gotten around to "finding" it might be another deal. They do not really have the facilities to work on them or discover what all they have. Nor do they work really fast. Nor will it be free or low cost, as it does incur money to detail all this work.

Please do not take this as disparaging the MVPA Archives. They have few facilities to work with, little to no budget, and work with no paid staff, it is all volunteer! Most of you have already been on this road, you can have a group of 30 people and 5 end up doing most of the work.

[lpcoating]

Lou,

I'm not sure where you have to send the coils to be cut apart but I will volunteer some lathe time to split them for you if that helps the cause.

Guy

[John Mc]

Was there ever any resolution to this?

My guess is that at worst, the new black coils are no more of a problem than the chrome ones when used with an electronic ignition, since the primary resistance is just about identical.

[rickf]

Yes and no, One of our members did some extensive testing and found that due to resistance issues the new coils could cause issues with electronic modules and since then they are offered for sale for distributor with points ignition only I believe. Lous post from Dec. 6 above explains the whole procedure he did and the effects on the electronic modules. Also his conversations with the seller and person that specced out the coils. To this date I do not think they have made any for the late model electronic ignition yet. You would have to contact Pete Debella Jeep parts and ask him about that.

[John Mc]

If I recall from the video (it's been a while since I watched it, the primary resistance of the chrome coils is almost identical to the new coils from Debella Jeep parts. My last communication with Peter DeBella on 4/6/21 he still had the warning up on the web site. He also said that he had sold some coils to a dealer, who is using it in his own truck with electronic ignition with no problems. There were also several sold to folks who put them in trucks with electronic ignition before the issue was known. As of that 4/6 communication he had not heard of any problems, but was leaving the warning up anyway. (The warning appears to be gone from the website now.)

My question was actually more along the lines of whether anyone had opened up a stock coil to determine the design details, since a couple of folks in this thread had talked about it.

[John Mc]

Just heard this back from Peter Debella:

They seem to be 100% fine. Mechanical and Electric Ignition. HOT weather environment. Tested. Everyone seems to be satisfied. Not one failure.

Regards,
Peter DeBella

[rickf]

Well, I am not an electrical engineer. I was an expert in automotive electrical systems which involved diagnosing regular electrical problems but Lou has gone far deeper into it than I have the knowledge or equipment to do. I figure I will wait till the end of summer and see what the outcome is then. These things have only been out for 6 months or so and most of that time has been on lockdown so nobody really going anywhere. I want to see what happens after they get some miles on them. I have had the chromies last me months and I have had them die in minutes. I have not had one take out a module yet and I hope they do not since you can no longer get the original modules.

[Lou]

If I had any faith in those aftermarket ignition coils, I would have not spent $150.00 for the NOS coil kit a few months ago. I am retired and that is a lot of money to me. The aftermarket coils also put out thousands of volts less then the NOS ones. Also, if you have an aftermarket coil and a NOS coil, pick them both up. Notice how much heavier the NOS coil is? That is because copper windings are heavy and the the aftermarket coils have less copper windings and that is why the secondary voltage is thousands of volts less. A simple ohm meter can also confirm this as the resistance values are out of spec on the aftermarket units.

[lpcoating]

Lou - were you able to dismantle an NOS and aftermarket coil to see the internals?

Guy

[Refit1701]

Did anyone ever cut apart a coil? I have a bad GI coil here and can have it apart in a few minutes on my lathe.

[rickf]

If you decide to cut it apart be aware that the oil inside the coil is very toxic! You do NOT want to get that on your skin or on your equipment.

[Refit1701]

Yeah, I'll have to drain the oil first though a hole in the bottom. I'll probably gently heat the case to facilitate that. Then cut it open with a parting tool over a tub, wearing gloves and a face shield at slow speed. Then solvent to remove the remaining oil.

If you decide to cut it apart be aware that the oil inside the coil is very toxic! You do NOT want to get that on your skin or on your equipment.