Bad Starter Relay Switch Quality

Discussion in 'Gen 1 & 2 - Engine, Exhaust, Drive Line & AC syste' started by DeepPower, Feb 25, 2015.

  1. DeepPower

    DeepPower Searchng4Truth

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    Is that more reliable? What is the advantage?
     
  2. Devin

    Devin 3.Slow

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    I can't say that it is more reliable. That and it is one more thing that can fail which would cause you to RMA your starter. However if all the fender relays are problematic, there could definitely be some wisdom in changing.
     
  3. Off Road SHO

    Off Road SHO Moderator Staff Member

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    If you change to a Gen 2 starter with its attached solenoid/relay, make sure you take care of the Gen 1 relay's OTHER duty too. And that is as a splice point. Any other wires that are on the battery side of the Gen1 fender mounted relay will need to be extended and moved down to the battery side of the Gen 2's starter. Don't forget this. It's important.

    Tom
     
  4. Devin

    Devin 3.Slow

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    Personally it sounds like too much work to me, and that space is a PITA to access on my back.
     
  5. DeepPower

    DeepPower Searchng4Truth

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    My Bosch starter is still good but it's good to know for future reference. In the meantime I'm having the ignition switch replaced and putting a TVS diode across the starter fender relay contacts to protect the relay.
     
  6. Devin

    Devin 3.Slow

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    That doesn't look like a SHO ignition switch. Did the 89s use a different type?
     
  7. Off Road SHO

    Off Road SHO Moderator Staff Member

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    BTW, for future reference: the fender mounted relay can be replaced with a standard Ford solenoid OR you can put in a Continuous Duty Solenoid as sold at electrical parts houses. I have 12 volt winches that I use in my business that employ the continuous duty type. Have not wore one of those out in 25 years of heavy duty use.

    Tom
     
  8. sperold

    sperold Last to Know Supporting Member

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    That is the 89 ignition switch, all right, and replacing it may solve the problem. It is a rotary apparatus and subject to sticking in the advanced position.

    The 89s have a whole host of parts that are 89 only (actually 86 to 89).
     
  9. DeepPower

    DeepPower Searchng4Truth

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    You have a part number for that switch?

    The new ignition switch would have fixed the problem, except when my mechanic tested it, it was bad, too! The NEW one! So in the meantime we rigged a switch under the dash to start the car until he can get me another one.

    BTW, I installed a Littelfuse SLD28-018 automotive TVS across the contact terminals on the starter fender relay and boy am I glad I did! This is a bi-directional Transient Voltage Suppressor (TVS) that takes care of the high voltage inductive kick that can happen when the fender relay disengages. This causes the starter solenoid, which is a big inductor, to quickly discharge, which can generate hundreds of volts. That inductive kick jumps across the terminals of the fender relay, and can weld the points together. You can feel the thump" from the energy discharging. This TVS lets the energy from the solenoid coil pass through the TVS instead of the relay, dissipating the voltage into the battery's series inductance. The SLD28-018 can handle spikes as high as 2200V.

    Well, they say you don't miss it until it's gone, but there must have been a "thump" before when I disengaged the starter because it's not there anymore. This will also increase the life span of the starter fender relay, and will especially extend the lifespan of the starter solenoid.
     
    Last edited: Mar 18, 2015
  10. MichaelDecker95MtxSho

    MichaelDecker95MtxSho Member

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    Devin, you answered my question before i could ask. Thank ypu. I thought there might be a wierd 2nd starter relay on the fender on a gen 2
     
  11. AREA 91

    AREA 91 PA SHO SHOP

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    I had a new starter relay stick on me in downtown Las Vegas after the California SHO Convention!!! I thought I was being smart by changing out the original one. The original one is back on the car, with no problems.
    I to, recommend a Motor Craft part.
     

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