Bullnose Bill Answer
by Ed

Resistor wire and ignition coil compatibility for 1980-1986 Ford F-Series trucks

Bullnose Bill points to a 1980s Ford F-Series ignition coil and resistor wire, explaining fitment and failure signs.

This Q&A session is powered by Bullnose Bill, Bullnose Garage’s advanced AI mechanic.
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Bill says:

Alright, let’s dive into the ignition coil resistor wire for your Bullnose Ford. This wire is a key component in the ignition system, reducing the voltage from the battery to prevent coil overheating.

Purpose of the Resistor Wire

  • Voltage Reduction: The resistor wire drops the voltage from 12 volts to about 9 volts during normal operation. This prolongs the life of your ignition coil and points.
  • Starting: During engine start, full battery voltage bypasses the resistor to provide a hotter spark.

Common Issues

  1. Starting Problems: If the truck cranks but doesn’t start, a faulty resistor wire might not be delivering the right voltage.
  2. Overheating Coil: If the coil gets too hot, the resistor wire might be bypassed or shorted.
  3. Voltage Testing: Use a multimeter to check voltage at the coil with the engine running. You should see around 9 volts.

Replacement Tips

  • OEM Spec: Stick with OEM-spec resistor wire to ensure proper voltage drop.
  • Routing: Ensure the wire is routed away from heat sources to prevent damage.
  • Connections: Check all connections for corrosion or looseness, which can cause voltage drop issues.

Pro Tips

  • Bypass During Testing: Temporarily bypass the resistor wire for testing purposes, but don’t run it this way for long — it’ll wear out the coil.
  • Check Grounds: Make sure all grounds are clean and secure, as poor grounding can mimic resistor wire issues.

If you’re unsure about any step, checking out related videos on the Bullnose Garage YouTube channel might be helpful. If you’ve got more questions, feel free to ask!

User avatar

User:

Where to find replacement resistor wire and ignition coil for 1980-1986 Ford F-Series

Bill avatar

Bill:

Finding a replacement resistor wire for your Bullnose Ford can be straightforward if you know where to look. Here are some options:

Where to Find Replacement Resistor Wire

  1. Auto Parts Stores: Check out local stores like AutoZone, NAPA, or O’Reilly. They often have listings for classic Ford ignition parts.

  2. Online Retailers: Websites like RockAuto or Summit Racing offer a wide range of parts for older vehicles. Just ensure the part matches your truck’s year and model.

  3. Specialty Suppliers: Consider suppliers that specialize in classic Ford parts. They might offer more accurate OEM-style replacements.

  4. Salvage Yards: Sometimes, you can find usable parts in salvage yards. It’s a bit of a treasure hunt, but you might get lucky.

Installation Tips

  • Compare Before Installing: Make sure the new wire matches the length and resistance of the original.
  • Secure Properly: Use clips or ties to keep the wire away from high heat or moving parts.

If you’re still searching, there may be more specific advice or suggestions on the Bullnose Ford subreddit, which can be a great resource. Let me know if there’s anything else you need!

This answer was written by Bullnose Bill, our AI shophand trained on hundreds of Bullnose-era Ford topics. He knows his way around old Ford Trucks.

As with all of Bill’s answers, it has been reviewed and approved by Ed Zenisek, the man behind Bullnose Garage and a real human being.

While we do our best to keep things accurate, always double-check any repair advice and use proper safety procedures. For real-world walkthroughs and more hands-on content, check out Bullnose Garage on YouTube or visit the BullnoseFord SubReddit.

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