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1987 70 HP, Choke Toggle, when does it turn off?

T

travbowls

New member
I recently got a boat with my first big 2-stroke outboard, 1987 Evinrude 70hp, runs great. I do understand 2-strokes from dirtbikes and Banshee's. The boat is an 84, and the motor is an 87, and the controls say a Johnson Powershift 2, so not sure if they came with the boat or the motor.

My question is for the electric choke toggle switch. The previous owner said you flip that up (and it goes back to center), which activates the choke, and then as the motor heats up, that choke steps itself down (gradually opens the butterfly valves I guess?). ALso note that my key does NOT push in for choke.

My question is how long does that choke stay "on" for after toggling up? My key doesn't seem to have an "on" or "acc" type of position either, just turn to start. So if I flip that toggle, and try to start, and it doesn't, so I turn the key back to off, then try again, I assume the choke is still on. But what if I wait 10 min? an hour? What if I realize I want the choke to be OFF? Just hate not really understanding that whole function, and I couldn't find this question answered before.

Thank you for any tips, pardon my newbness.
 
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Totally wrong.-----The red lever on the primer is for manual operation.-----When you flip the choke switch up it opens the primer valve to inject fuel for cold starting when the motor is cranking.-----No choke flappers anywhere.----Not automatic in operation either.
 
Thanks for the fast reply!
Aaah, so I guess it's really more of an enrichener? So then I guess, when would that primer valve then close back up, and not inject fuel while cranking? Basically, if it takes a few cranks to start, do you need to flip that tiggle each time?

And the Fast idle arm advances the timing, but also adds more fuel right? So there is no choking on this motor at all huh, only extra fuel at startup? Seems like a recipe for flooding, no?
 
I strongly suggest you get rid of that Mickey Mouse toggle setup and purchase the proper six terminal push key to choke/prime ignition switch that engine requires.

********************
(Fuel Primer Solenoid Function)
(J. Reeves)

The RED lever...... The normal operating/running position is to have that red lever positioned over top of the solenoid and aimed at the other end of the solenoid, gently turned to its stop. This is the normal/automatic mode position. Pushing the key in opens the valve within the solenoid allowing fuel to pass thru it in order to prime and start the engine. Looking upon this solenoid as a electric choke results in a better understanding of it.

Having that red lever turned in the opposite direction, facing away from the solenoid, allows fuel to flow thru it to the crankcase area. One would only turn the red lever to this position in a case where the battery might go dead and the engine had to be started via the rope pull method. Look upon putting the red lever in this position as moving a choke lever on a choke equipped engine to the full closed position. Either one would supply fuel to the crankcase/engine for starting purposes BUT if left in that position while running would flood the engine.

The later model primer solenoids are equipped with a schrader valve, used for attaching a pressurized can of fogging oil etc, available at your local dealership with complete instructions.

Pumping the fuel primer bulb up hard fills the carburetor float chambers of course, but that process also applies fuel pressure to the primer solenoid.

The two small hoses leading from the primer solenoid branch off via tees to each fuel manifold section that would feed fuel to the individual cylinders.

Pushing the key in activates the primer solenoid to allow fuel to flow thru it to the intake manifold passageways. Cranking the engine over causes the fuel pump to engage which in turn sends fuel pulses to the primer solenoid via the 3/8" fuel hose.

Some engines incorporates the "Fast Start" feature which automatically advances the spark electronically so no advance of the throttle is required for starting.
Engines that do not have the "Fast Start" feature will be required to have the throttle advanced slightly.

Starting procedure: pump fuel bulb up hard, crank engine and push the key in at the same time. When the engine fires/starts, release the key so that it falls back to the run position.

Bottom line..... Look upon the primer solenoid as an electric choke.

********************
 
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Since you do not have the push-to-choke key switch, holding the toggle up opens the primer valve and holds it open as long as you are holding the toggle. Turn loose, and it closes. While it is open and cranking, fuel flows to the intake manifold for a richer starting mixture. Don't worry about flooding, unless you are doing it to a warmed-up motor. Even then, it will clear itself out if you turn loose and crank some more.

Fast idle arm does just that--gives it a bit of throttle without putting it into gear.
 
That primer works a lot better than the choke flappers !!----An excellent set-up that was used from 1980 to 2007.---Not a recipe for flooding at all.----Learn how it works !
 
fdrgator said:
Since you do not have the push-to-choke key switch, holding the toggle up opens the primer valve and holds it open as long as you are holding the toggle. Turn loose, and it closes. While it is open and cranking, fuel flows to the intake manifold for a richer starting mixture. Don't worry about flooding, unless you are doing it to a warmed-up motor.
Click to expand...

Thank you, this is exactly what I was wondering about. So the toggle is acting as pushing the key in. So when I'm cranking, if it seems like there's not enough fuel, I can just lift the toggle again, and it will spray some more fuel.
It would be nice to have a control box made for this exact engine, but I guess I will try this setup until I know more about the motor etc. Previous owners were having years of use like this, so I guess it works.

Thanks again for all the replies and info
 
The electric primer is a valve, it is NOT a pump.-----Primer must have fuel pressure to it to work.----Pressure comes from the fuel pump when engine is cranking.----Or from the bulb on the hose when it is tight.
 
After doing a little more research, looks like this is the control box based on the style of key that it has:

The 73 Pistol Grip Key Series came out in 1973 and were mostly used in control boxes that had a seperate choke switch from the ignition (not push to choke). These were made/stamped Pollak.

Seems so odd to put 1973 controls with a 1987 motor, which I assume had some mechanical differences. But I guess people do what they do. It would be nice to swap this out to one from the correct era.
 
travbowls said:
After doing a little more research, looks like this is the control box based on the style of key that it has: The 73 Pistol Grip Key Series came out in 1973 and were mostly used in control boxes that had a seperate choke switch from the ignition (not push to choke). These were made/stamped Pollak.

Seems so odd to put 1973 controls with a 1987 motor, which I assume had some mechanical differences. But I guess people do what they do. It would be nice to swap this out to one from the correct era.
Click to expand...

It was common knowledge back then that any control box with its wiring harness could interchange with any engine SO LONG AS the main electrical plugs were the same color..... Black, Yellow, or Red.

No doubt, at one time, the engine was a 1973 model... the engine blew... the boater picked up the present engine and didn't want to bother changing the control box and wiring harness. Perhaps the seller still has the other box/harness??
 
Any control with a big red plug will work on a motor with a big red plug on the wiring harness.----I agree the newer controls are a bit smoother / better.-----It does not seem odd to me at all that you can find an older control with a newer motor.
 
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