Remote Solenoid Issue?

Discussion in 'Electrical Systems' started by sandiego74, Jun 30, 2019.

  1. sandiego74

    sandiego74 Veteran Member Lifetime Gold Member

    Messages:
    1,160
    Likes Received:
    77
    Joined:
    Feb 23, 2009
    Location:
    San Diego, CA
    I’m going to call MadElectrical one more time and ask why the relay is necessary, in his opinion. If it’s not convincing enough, and I get a few others telling me to rewire it, I’ll rewire it.
     
    muscl car likes this.
  2. biker

    biker Veteran Member

    Messages:
    2,501
    Likes Received:
    972
    Joined:
    Dec 7, 2014
    Location:
    Canada
    If I'm reading things right, and I'm no expert, I think the solenoid in the trunk area is to avoid having a live high amp 12 volt cable running from trunk to starter. The solenoid should ensure the starter cable is only live during cranking. I'm sure it will work fine without it.
     
  3. muscl car

    muscl car Veteran Member Lifetime Gold Member

    Messages:
    22,899
    Likes Received:
    1,467
    Joined:
    Jul 8, 2001
    Location:
    SoCal High Desert
    My 12v cable is sleeved in 3/8th fuel line and convoluted tubing
     
  4. biker

    biker Veteran Member

    Messages:
    2,501
    Likes Received:
    972
    Joined:
    Dec 7, 2014
    Location:
    Canada
    Oh, believe me....I'm NOT the minister of safety in any way... If it were me, I'd eliminate the trunk relay, especially if you have the big cable routed and protected.
     
    muscl car likes this.
  5. sandiego74

    sandiego74 Veteran Member Lifetime Gold Member

    Messages:
    1,160
    Likes Received:
    77
    Joined:
    Feb 23, 2009
    Location:
    San Diego, CA
    So... Mark at MadElectrical informed me that the reason for the small relay on the firewall is to cut power immediately to the ignition post on the starter when not in use. He says the coils inside the create a strong enough magnetic field that will keep the starter engaged out to the flywheel, even after the engine has started, when using the jumper cable from the battery post to the ignition post in most modern starters. Interesting concept.
     
  6. sandiego74

    sandiego74 Veteran Member Lifetime Gold Member

    Messages:
    1,160
    Likes Received:
    77
    Joined:
    Feb 23, 2009
    Location:
    San Diego, CA
    Have you had any issues with this setup, and is this a newer starter? I’ve got the same starter as you, I think.
     
  7. McCune

    McCune Veteran Member

    Messages:
    1,225
    Likes Received:
    270
    Joined:
    Aug 22, 2015
    Location:
    st.george utah
    Electromagnetic field coils with not leave the starter drive engaged in the ring gear after the engine is started. A permanent magnet field starter will absolutely hang the drive up in the ring gear for a few seconds after start up. The starter pictured above is a electromagnetic starter.
     
    sandiego74 likes this.
  8. Jim Streib

    Jim Streib https://www.flickr.com/photos/121766713@N04/albums

    Messages:
    404
    Likes Received:
    67
    Joined:
    Apr 6, 2004
    Location:
    Saint Louis, MO USA
    While I've heard this MANY times before that the vehicles wiring is protected by additional layers and/or routing, my concern is what happens if one is in a bad enough accident to where this live cable, or any live cable, were to get shorted to ground ?. How would routing or additional coverings protect from this ?. Some may say, well I have a master on/off switch to kill power but I really doubt if you get in a bad enough accident that you might be even able to get to the switch to turn it off if you have been knocked out.
    Ideally one would want to have the wiring protected by something that automatically does this and they have had out for YEARS a thing called fuses. Yep, fuses open up when the current exceeds their specifications and do not need anyone to help them out to do so. One just cannot randomly put any fuse on any wire but if done properly if the current deamnds are larger than the wire, then the fuse will blow. A fuse, circuit breaker, fusible link, and such are not there to protect the device BUT to protect the wire.
    Some will say that no manufacturer puts any fuse on a starter circuit and years ago this was true but they learned and others ARE learning. Years ago, I never knew here were fuses that were rated at 200A and higher but they are out there and there is a need for them.

    Factory Jaguar starter fusing:

    [​IMG]

    Chevrolet Cruze:

    [​IMG]

    From publications:

    [​IMG]

    [​IMG]

    Jim
     
    sandiego74 likes this.
  9. muscl car

    muscl car Veteran Member Lifetime Gold Member

    Messages:
    22,899
    Likes Received:
    1,467
    Joined:
    Jul 8, 2001
    Location:
    SoCal High Desert
    Lokar makes an interior battery disconnect handle that connects to the battery disconnect by a morse cable ( shifter cable) . This allows the driver to turn off the power from the driver's seat and also from outside the vehicle's tail panel

    As I've mentioned I've seen to many over engineered set ups such as from MAD electrical fail at the track and never seen a moroso battery disconnect (master cutoff ) set up fail


    https://www.jegs.com/i/Lokar/625/13...8G9WrmZHiWChgWbIkx55mmFGbSovUPN0aAjiLEALw_wcB
     
    sandiego74 likes this.
  10. Jim Streib

    Jim Streib https://www.flickr.com/photos/121766713@N04/albums

    Messages:
    404
    Likes Received:
    67
    Joined:
    Apr 6, 2004
    Location:
    Saint Louis, MO USA
    Not to get in an argument here but if no one is around to turn off a moroso battery disconnect what happens with a short to ground ?.

    Someone HAS to turn the switch off to stop current flow whether is is in an undesired situation that causes no damage like when storing the car or to stop the flow of current should a short occur past the switch. I would like something that disconnects power if a fault occurs and if it requires replacing a part, so be it. A lot cheaper replacing an inexpensive part than the whole car.

    While it's unknown what caused the below, could an inexpensive properly placed fuse have prevented this ?. A master on/off switch that was forgotten to be turned off could have also allowed this happen IF it was indeed an electrical fire.

    [​IMG]

    Jim
     
    dave@ztech and sandiego74 like this.

Share This Page