Author Topic: Cylindrical Resistor in the Coil Wire  (Read 2501 times)

Tomnistuff

  • Full Member
  • Gold
  • *****
  • Canada, Qc, Levis
  • Posts: 930
Cylindrical Resistor in the Coil Wire
« on: May 26, 2017, 02:13:48 »
Why would my 230SL have a cylindrical resistor in the middle of the length of the coil wire?  The resistor is about 3 inches long, 1/2 inch in diameter and has a hole in each end with a threaded sharp pointed pin inside, similar to the spark plug boots.  The coil wire is cut in half and the resistor is screwed onto the two halves of the coil wire.  The item is dark brown Bakelite material.

It's been on the car for 30 years.  The only reason I ask is that it doesn't grip the new Packard wires I made very well and I would like to eliminate it.

I don't remember the resistance, but can check it again tomorrow if it's important.

Is it for noise suppression?

Tom Kizer
Apparently late 1966 230SL 4-spd manual (Italian Version)
Owned since 1987 and wrapping up a full rotisserie restoration/modernization.
Was: Papyrus White 717G with Turquoise MBtex 112 and Kinderseat
Is: Dark Blue 332G with Dark Blue Leather (5300, I think)

Tyler S

  • Full Member
  • Platinum
  • ******
  • USA, CA, Encinitas
  • Posts: 1613
Re: Cylindrical Resistor in the Coil Wire
« Reply #1 on: May 26, 2017, 02:48:10 »
You are correct in that it is for noise supression. Was most likely added years ago by someone who listened to a lot of AM radio. If your car came from the factory without the noise supression option then this and other items may have been added when the radio was installed or to rid interference.
1968 (67) 250sl. 4 speed manual. DB180 Silver
1955 220 Cabriolet A. White Grey
2019 E450 Wagon. Majestic Blue
1936 Ford PU Flathead V8. Creme on tan interior.
1989 Volkswagen T3 Westfailia Campmobile. Dove Grey (blue)