How's a choke solenoid work?

Discussion in 'Bubba's Outboards' started by waynesburgjay, Nov 3, 2009.

  1. waynesburgjay

    waynesburgjay New Member

    Messages:
    1,960
    State:
    Pennsylvan
    How's a choke a solenoid work? I have one on my 20 hp mariner that's not working. It's getting power to it.
     
  2. playin4funami

    playin4funami New Member

    Messages:
    4,104
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    Saronville Ne.
    the choke solenoid is not really the correct terminology,it would be called a valve actuator. how it works is that it opens or closes the butterfly valve on the carburator. when you close it it restricts the amount of oxygen that gets to the carb. and causes a fuel rich environment that makes it easier to start the motor when cold. there is a coiled "wire" inside the valve acuator that expands as it warms,it is warmed by the small vent tube coming off the engine,as it expands it moves the acuator rod that controls the butterfly on the carb opening it to allow more air into the fuel mixtureto run correctly as it reaches correct operating temperatures.
    On newer style engines a electronic valve acuator is used which works almost exactly the same except instead of using a vent tube to carry heat to the actuator it is read by a electronic "sensor" which then tells the actuator when to start opening.

    hope this helps,if its messed up just take it off and replace it as most all I've ever seen are a sealed unit that just gets tossed when they go bad.
     

  3. smokey869

    smokey869 New Member

    Messages:
    966
    State:
    frederickt
    if its an older one that you have to push in the key to actuate it is a solonoid, if its got power and ground and doest work replace it, you need to check it with it hooked up, because if you have a poor power feed it will light a test light but wont kick the solonoid, hope this helps you
     
  4. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    It is vertuly a electro magnet. Current creates a magnet which in turns pulls the little plunger down inside the cylinder and closes off the shoke butterfly.
    When the power is disengaged to it it turns the plunger loose and the spring opens the butterfly back open.
     
  5. corklabus

    corklabus New Member

    Messages:
    359
    State:
    West Virginia
    I'm sorta in a delema with mine also : '74 115 Evinrude. The spring on my "actuator" has been stretched and screwed up. Boat would start and run fine, but bogg out at wide open throttle. I inhooked the messed up spring and boat ran like a new one. ( mean while I was using the manual choke thing on the other side of the motor) I need to find a replacement spring or at least a part number for one so I can try to locate one. It seems this spring just screws onto the actuator and then hooks somehow to the choke lever above it, but I'm not sure if there is a separate connector involved at the rod lever end. I'd settle for the manual thing, but I have to remove the engine cover every time and that reaaly sucks. This is just the least of my problems with this boat, but the other stuff is probbably just gonna suck big money that I won't have for a long time.
     
  6. catman-j

    catman-j New Member

    Messages:
    1,020
    State:
    Eastern Nebr
    I have one on my chrysler project boat (60hp) that isn't working but I have yet to try to trouble shoot it. Nothing electrical on my boat worked except the starter. On yours maybe you could set up a manual choke with a throttle cable off of an old lawn mower or something.
     
  7. corklabus

    corklabus New Member

    Messages:
    359
    State:
    West Virginia
    A manual cable might be an idea if all else fails, but it seems like a lot of work to replace a ten cent spring. I guess I just need to take my lazy tail over to the boat shop.