Welcome, Guest
Username: Password: Remember me
  • Page:
  • 1
  • 2

TOPIC:

Coil wire getting hot 28 May 2020 14:33 #826765

  • 1981kz750ltd
  • 1981kz750ltd's Avatar Topic Author
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 72
  • Thank you received: 13
I' m working with a 1976 900 LTD with a wiring harness from a 1979 1000cc ( I don't know if it was an LTD). Problem is the coil feed wire ( yellow with red stripe) is heating as is the red wire from the ignition switch coming from kill switch/start button. Using the Dyno coil setup. Any solutions for resolving this? Thanks.

Please Log in or Create an account to join the conversation.

Coil wire getting hot 28 May 2020 15:34 #826770

  • 73z1
  • 73z1's Avatar
  • Offline
  • Member
  • Member
  • Posts: 275
  • Thank you received: 52
The coils are drawing more amps then the wire can supply without over heating.
Either the coil loop has shorted or the coils need a larger wire.
Check if coils are same temperature or differ.
The following user(s) said Thank You: 1981kz750ltd

Please Log in or Create an account to join the conversation.

Coil wire getting hot 28 May 2020 20:02 #826790

  • Mikaw
  • Mikaw's Avatar
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 1634
  • Thank you received: 362
Check the scotch lock connection from the red wire of dyna pick ups, to the yellow with red. It could be a bad connection. Check voltage at the coil positive where the yellow/red connects. The dyna s are power hogs. Could also be in the ignition switch. The solder connections go bad

1976 KZ 900 A4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
Attachments:
The following user(s) said Thank You: 1981kz750ltd

Please Log in or Create an account to join the conversation.

Coil wire getting hot 28 May 2020 22:38 #826801

  • cb900f
  • cb900f's Avatar
  • Offline
  • Member
  • Member
  • Posts: 57
  • Thank you received: 12
Check to see that the coils have the proper input resistance and (assuming resistance is correct) if the coil input is shorting to ground via the coil's iron core laminations.
The following user(s) said Thank You: 1981kz750ltd

Please Log in or Create an account to join the conversation.

Last edit: by cb900f.

Coil wire getting hot 29 May 2020 14:08 #826873

  • Mikaw
  • Mikaw's Avatar
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 1634
  • Thank you received: 362
Not sure what model you have but this will help you test the coil for proper ohms



1976 KZ 900 A4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
Attachments:
The following user(s) said Thank You: 1981kz750ltd

Please Log in or Create an account to join the conversation.

Coil wire getting hot 10 Jun 2020 16:10 #827807

  • 1981kz750ltd
  • 1981kz750ltd's Avatar Topic Author
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 72
  • Thank you received: 13
Thank you for all the input. To follow up someone had previously repaired the handlebar kill switch with JB Weld which I believe has a lot of graphite in it. As it deteriorated the powdered JB Weld shorted the wires in the kill switch. Have repaired again with JB Weld clear epoxy.

Please Log in or Create an account to join the conversation.

Coil wire getting hot 11 Jun 2020 08:37 #827875

  • F64
  • F64's Avatar
  • Offline
  • Member
  • Member
  • 81-KZ440D2
  • Posts: 331
  • Thank you received: 56
JB weld should not be conductive.
screenshot via www.jbweld.com/faqs
81-KZ440-D2. Louis Dudzik's GM HEI ignition module converted 2015--no issues, Motogadget m-unit blue.
Attachments:

Please Log in or Create an account to join the conversation.

Last edit: by F64.

Coil wire getting hot 12 Jun 2020 21:56 #828033

  • 1981kz750ltd
  • 1981kz750ltd's Avatar Topic Author
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 72
  • Thank you received: 13
Whatever it was I can only surmise. Grey epoxy like material deteriorated to the degree it was causing a short. Whatever it was is now gone and no more short.

Please Log in or Create an account to join the conversation.

Coil wire getting hot 12 Jun 2020 22:23 #828035

  • F64
  • F64's Avatar
  • Offline
  • Member
  • Member
  • 81-KZ440D2
  • Posts: 331
  • Thank you received: 56
are you still having issues with the coil wire getting hot?
81-KZ440-D2. Louis Dudzik's GM HEI ignition module converted 2015--no issues, Motogadget m-unit blue.

Please Log in or Create an account to join the conversation.

Coil wire getting hot 13 Jun 2020 07:17 #828046

  • 1981kz750ltd
  • 1981kz750ltd's Avatar Topic Author
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 72
  • Thank you received: 13
No. Wire heating problem is gone.

I've attached a picture of the inside lower half of the kill switch. Left side of the round disc that supports the brown and yellow/red kill switch wires show evidence of damage repair and partial remains of whatever substance was used to repair it. This repair substance had deteriorated and become powdery, apparently causing the short.

However.

There could be an alternative or additional cause or factor contributing to the kill switch short circuit.

For those of you who have yet to experience the joy of disassembling and reassembling these kill/run switches, they contain 3 tiny springs with a tiny ball bearing atop each one. Is it possible that after 44 years one of these little ball bearings deteriorated to the degree that its rust or flakes contaminated the switch internally, creating the short?

Or, did the previous party who repaired the broken disc not reassemble it correctly and one escaped its detent position, causing the short? Because I found only two when it came apart. But, they are tiny so it could have gotten away upon dissambly.

I'd suggest to anyone taking one of these apart, do it inside a plastic bag. if the springs or balls drop out they're contained in the bag.

Btw. These little ball bearings you can get at a good hardware store. :)
Attachments:

Please Log in or Create an account to join the conversation.

Coil wire getting hot 13 Jun 2020 07:23 #828048

  • 1981kz750ltd
  • 1981kz750ltd's Avatar Topic Author
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 72
  • Thank you received: 13
No. Wire heating problem is gone.

I've attached a picture of the inside lower half of the kill switch. Left side of the round disc that supports the brown and yellow/red kill switch wires show evidence of damage repair and partial remains of whatever substance was used to repair it. This repair substance had deteriorated and become powdery, apparently causing the short.

However.

There could be an alternative or additional cause or factor contributing to the kill switch short circuit.

For those of you who have yet to experience the joy of disassembling and reassembling these kill/run switches, they contain 3 tiny springs with a tiny ball bearing atop each one. Is it possible that after 44 years one of these little ball bearings deteriorated to the degree that its rust or flakes contaminated the switch internally, creating the short?

Or, did the previous party who repaired the broken disc not reassemble it correctly and one escaped its detent position, causing the short? Because I found only two when it came apart. But, they are tiny so it could have gotten away upon dissambly.

I'd suggest to anyone taking one of these apart, do it inside a plastic bag. if the springs or balls drop out they're contained in the bag.

Btw. These little ball bearings you can get at a good hardware store. :)

Please Log in or Create an account to join the conversation.

Coil wire getting hot 13 Jun 2020 08:19 #828051

  • F64
  • F64's Avatar
  • Offline
  • Member
  • Member
  • 81-KZ440D2
  • Posts: 331
  • Thank you received: 56
Good job!!!
81-KZ440-D2. Louis Dudzik's GM HEI ignition module converted 2015--no issues, Motogadget m-unit blue.

Please Log in or Create an account to join the conversation.

  • Page:
  • 1
  • 2
Powered by Kunena Forum