Kitfox Aircraft Stick and Rudder Stein Air Grove Aircraft TCW Technologies Dynon Avionics AeroLED MGL Avionics Leading Edge Airfoils Desser EarthX Batteries Garmin G3X Touch
Results 1 to 8 of 8

Thread: Starter solenoid

  1. #1
    Senior Member Peteohms's Avatar
    Join Date
    Sep 2008
    Location
    Leander, TX Hangared @ KGTU
    Posts
    272

    Default Starter solenoid

    My Starter solenoid started giving out on me. The attached picture is what my starter solenoid looked like and also what my new one looks like. The new one is an S 5049P.
    Attached Images Attached Images
    Last edited by Peteohms; 10-11-2013 at 06:31 PM.
    Pete
    Leander, TX
    Model III SN 1000
    912
    Grove

  2. #2
    Senior Member Peteohms's Avatar
    Join Date
    Sep 2008
    Location
    Leander, TX Hangared @ KGTU
    Posts
    272

    Default Re: Starter solenoid

    On the S5049P the terminals are Battery (lower large term.), Switch (lower small term.) and Starter (upper large term.)

    What I'm concerned with is that my old solenoid had the starter and battery wires swapped. Can they be switched like that?
    Pete
    Leander, TX
    Model III SN 1000
    912
    Grove

  3. #3
    Senior Member jtpitkin06's Avatar
    Join Date
    Jan 2010
    Location
    Greenville, TX
    Posts
    640

    Default Re: Starter solenoid

    Not a problem on that type contactor.



    There are two common types of contactors used on aircraft, a 3 terminal and a 4 terminal.


    On a three terminal solenoid contactor the switch connection powers the solenoid closed by grounding through a master switch or starter switch. There is an internal connection on the battery side to the windings of the coil so positive voltage is always present at the small switch terminal. If the battery is connected to the wrong side of the large terminals, the solenoid will not close by grounding the small terminal.



    A four terminal contactor like the one pictured typically has no internal connection to the solenoid windings. One of the small terminals must be connected to a power source. The control circuit may be either positive to close or grounding to close. Four terminal contactors have no restriction on which of the large terminals connects to the battery or the starter. So hook it up either way and it will work just fine.

    The above types are the most common, there are many variations on the basic types dealing with internal connections. It’s pretty simple to test them with a battery to figure out what’s going on inside.



    One additional note: Be aware that starter solenoids should be mounted upside down, terminals down. If mounted terminals up, a hard bump on landing can cause the solenoid slug to slap closed and engage the starter. Battery contactors are mounted terminals up to remain connected if you bump them on landings.


    John

  4. #4
    Senior Member Peteohms's Avatar
    Join Date
    Sep 2008
    Location
    Leander, TX Hangared @ KGTU
    Posts
    272

    Default Re: Starter solenoid

    Thanks John. I thought I was ok. But, even though the replacement solenoid looks the same as the old solenoid, I couldn't find anything that says why one terminal is marked starter and the other battery in the instructions. It is firewall mounted.
    Pete
    Leander, TX
    Model III SN 1000
    912
    Grove

  5. #5
    Senior Member SkyPirate's Avatar
    Join Date
    Apr 2009
    Location
    Edgar Springs MO
    Posts
    1,841

    Default Re: Starter solenoid

    It is the same as a UTV winch selinoid, i used one on a wireless remote control 12 volt tree stand that will lift a guy in a wheel chair up 16'
    Chase
    Model 5 OutBack
    912 UL

  6. #6

    Join Date
    Dec 2009
    Location
    Netherlands
    Posts
    197

    Default Re: Starter solenoid

    What do you mean by 'upside down'? The pic shows a kind of solenoid I have, but mine is mounted to the FW (vertical...)

  7. #7
    Senior Member
    Join Date
    Jul 2013
    Location
    Highlands Ranch, CO
    Posts
    404

    Default Re: Starter solenoid

    He means with the terminals facing down. Many don't do it, but it is the best (safest) approach. Perhaps you could find or fabricate an 'L' bracket to mount it with the terminals facing down.

    Greg

  8. #8
    Senior Member jrevens's Avatar
    Join Date
    Aug 2009
    Location
    Arvada, CO
    Posts
    2,146

    Default Re: Starter solenoid

    This has been discussed in great detail on this forum... check out:

    http://www.teamkitfox.com/Forums/sho...light=solenoid

    The right side up/upside down issue pertains specifically to Series 70 White-Rogers solenoids, which are very commonly used in aircraft. It may be a consideration in other brands/types also, but not necessarily yours. There are solenoids that are designed for horizontal mounting.
    John Evens
    Arvada, CO
    Kitfox SS7 N27JE
    EAA Lifetime
    Chap. 43 honorary Lifetime

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •