40hp Electric Choke: How does it work?

[Mark42]

After mounting and connecting the wire harness to the 1993 Evinrude, I turned on the ignition (Johnson Command control box, the big one with padded top) and tested the electric choke. I hear a "click" sound from a solenoid on the motor near the throttle linkage, but I don't see how that solenoid does anything. I also noticed that the carbs don't have the traditional choke butterfly on them. So how does this work? Is the red knob on the solenoid supposed to move when it is energized? <br /><br />Thanks,<br />Mark

 

[rickdb1boat]

Re: 40hp Electric Choke: How does it work?

When you push the choke(Primer) button(Key switch), it shoot fuel dirctly into the cylinders via the primer, which has fuel pressure built up in it. The red knob does not move when you do this. It is for Manually choking the engine if the primer fails. It should be parallel to the primer in the normal runing position. If you hear the selonoid clicking, it's working. Hold the primer switch in for a count of 5 before you try and start the motor and continue to hold it in at cold start...

 

[Mark42]

Re: 40hp Electric Choke: How does it work?

Thanks Rick!

 

[Joe Reeves]

Re: 40hp Electric Choke: How does it work?

Mark.... The later model engines have a primer solenoid, not a choke. However, you can look upon it as a electric choke for operating purposes.<br /><br />The RED lever on the primer solenoid should be over top of the solenoid, pointing directly at the other end of the solenoid to be in the automatic mode.<br /><br />When you push the key in to operate the solenoid (choke), that allows fuel to flow through the solenoid, out the small hoses that is attached to it, to the intake manifold, which primes the engine with raw fuel.<br /><br />The difference between the choke setup and the primer solenoid is that with the primer solenoid, the fuel does not need to be drawn through the carburetor assemblies.<br /><br />Now, that RED lever.... should the battery ever go dead and you need to operate the primer solenoid (choke), turn the RED lever so that it faces away from the solenoid. This will allow fuel to flow through the solenoid to the intake manifold each time you pump the fuel primer bulb, and also with each revolution of the engine. Be sure to return that RED lever to its normal (automatic) position so that you don't flood the engine.

 

[Mark42]

Re: 40hp Electric Choke: How does it work?

Joe,<br /><br />Thanks for the detail. I noticed then cleaning the control box that the "lift to start" lever operates a switch internal to the control box. I thought that this switch should also operate the primer solenoid, but it doesn't. I don't have a wire diagram for the control box, just the motor. <br /><br />Should I open the control again and check the operation of this switch? <br /><br />I want to ensure that all systems are operating properly before I put the motor in a tank of water (garbage can) and start it. I am doing this as a starting only test and not to break in the motor. This is a newly rebuilt 40 hp and I have not run it yet. Althoug the rebuilding shop has wet tested it. I see telltale earmuff water marks on the lower case.<br /><br />PS the low oil level alarm is working fine. The throttle friction adjustment is working, and removed all old lube from control surfaces and added a light coating of the blue water proof grease. Anthing else I should check on the control box?

 

[Joe Reeves]

Re: 40hp Electric Choke: How does it work?

Mark... If you're speaking of the white switch that has a plunger which rides against the throttle cam, that "Lift Lever" has nothing to do with that.<br /><br />That switch is a cutout switch that disables the starter solenoid circuit when the large throttle/shift lever is moved forward or backwards.<br /><br />That lift lever simply applies some throttle for starting without putting the engine in gear.<br /><br />No offense intended but it would be a good idea for you to obtain a service manual for that engine to avoid making an expensive mistake.

 

[Mark42]

Re: 40hp Electric Choke: How does it work?

Joe,<br /><br />No offense taken. I did purchase the OMC manual for the motor, but it does not cover the particular control box I have. Although it does show the wire connections and routing in photos. I guess I should have researched the solenoid better before posting.<br /><br />Thanks for your help.<br /><br />Mark.