1972 electric shift

[jay_merrill]

Re: 1972 electric shift

One thing that makes me curious at this point is how the Evinrude control unit works from an electrical perspective. I've never had one and would love to know how it handles the issue of throttle position when changing gears. Since the Evinrude unit uses push buttons to send electrical signal to the appropriate place, just like our home made versions would, I wonder how (or if) gear changing is possible with the throttle advanced.

 

[jameskb2]

Re: 1972 electric shift

I don't know. I have the Johnson controls, not the 'Rude.

I imagine there's a cam at the bottom of the throttle lever that "locks out" the buttons. Something with a groove in it that would hold the buttons in the position they are once advanced.

Speculation, don't have one to inspect. The Johnny controls advance the throttle forward and backwards, straight up being neutral throttle.

Interesting point. The 'Rude control's throttle only advances forward.

 

[F_R]

Re: 1972 electric shift

The Evinrude push buttons have a groove on their bottom ends. There is a plastic slider bar connected to the throttle lever, sliding in those grooves. The slider bar is made such that the buttons can only be pushed at fairly slow throttle position. Once the button is pushed, the throttle can be advanced whether it be forward or reverse. There is also a "bump" in the throttle movement to let you "feel" the correct position for starting the motor.

 

[jameskb2]

Re: 1972 electric shift

Something just dawned on me here....

You have the idea of hooking up the shift diode power to the switch, in conjunction with the power from battery. The intention is to supply power to the solenoids once the engine is turned off, keeping it in neutral until the rotation of the flywheel ends.

However, this will also back feed 12v to the battery, fuse block, and even key switch. I suppose I am going to have to add ANOTHER diode in the wiring to halt that. I'll have to add one in between the fuse block and the shift switch so that 12v won't get back to the fuse block. If I don't do this, it could just ignore the key switch, and the engine would continue running. It appears the shifting power / switching is going to have to be isolated from the rest of the boats power system in order to function properly. I wonder if I can just feed the solenoids in the lower unit from the shifting diode alone. Hmmm..... Leave the battery power out of the loop. Nope, can't do that. My push button for the starter wouldn't have power. Sheesh. I guess the diode to isolate the power from the fuse block will have to be put in. It's going to have to be heavy...I don't know (yet) what the starter solenoid draws amp wise.

 

[jay_merrill]

Re: 1972 electric shift

I don't know that it would. I suppose there could be one or more diodes in the Shift Switch but its pretty small, with a lot of wires running into it, so there wouldn't much room for any.

If you think about this in terms of how it all operates, there are basically three scenarios - not running with key off, not running with key on, and running with key on.

In the not running with key off, there is no DC voltage either to the Ignition switch (purple wire) or from the Shift Diode (purple/green wire), so there is no problem.

When the key switch is on but the motor is not running, there would be voltage from the battery but none from the Shift Diode. Again, no problem.

In the last situation, with the key on and the motor running, voltage would enter the switch in parallel from both the Shift Diode and the Rectifier so, likewise, there would be no back flow.

 

[jameskb2]

Re: 1972 electric shift

Yes, but there is a diode at the control, like the one in the engine compartment that supplies power from the stator as we've covered.

Since I am changing the key switch from an off / on / start, to an off / on, and using a push button to activate the starter, my wiring is shown in the diagram I made.

If I added the shift diode power from the engine to the switch, it would feed the power in circuit too. Adding it to the rough schematic I show in this thread, would give 12v power to the fuse block and key switch from the shift diode fed by the stator.

I have to take some more time to think this through, it's a little more complicated than I initially thought. I do agree that the shift diode power from the stator should be implemented in order to "hold" the solenoids in the cut off position until the engine stops.

I'll take a good hard look at all systems, power requirements and implementation before I go further. I'll repost here with what I come up with once I figure it out.

Thanks for the input though, really. I wouldn't have thought to have the shift diode feed from the stator without your insight.

 

[jay_merrill]

Re: 1972 electric shift

Think of it this way - as long as the flywheel is rotating, there is voltage coming from both the Shift Diode and the Rectifier, but once you turn the Ignition switch to the off position, that circuit is opened and no voltage goes to the Shift Switch from the Rectifier/Ignition Switch. But ..... opening that circuit also closes the path back to both the Rectifier and the Battery.

 

[wavrider]

Re: 1972 electric shift

Interesting thread,

I have the 71 rude 60hp electric shift.

the ignition conversion can be done with an epoxy filled coil. automotive type, a mopar ballast resistor and condensor.

works great mine runs like a champ so far no problems

 

[F_R]

Re: 1972 electric shift

This seems to be getting out of hand. The blocking diode in the control keeps the alternator from feeding the ignition circuit after the key is turned off. If it were not for the blocking diode, the motor would keep running after you turn it off.

 

[jameskb2]

Re: 1972 electric shift

Think of it this way - as long as the flywheel is rotating, there is voltage coming from both the Shift Diode and the Rectifier, but once you turn the Ignition switch to the off position, that circuit is opened and no voltage goes to the Shift Switch from the Rectifier/Ignition Switch. But ..... opening that circuit also closes the path back to both the Rectifier and the Battery.

I understand what you are saying Jay. Look at my drawing. Power in from the battery, to key switch. Key switch to fuse block. Fuse block to shift switch.

If I add direct 12v power served by the shift diode to the shift switch, then killing battery power to the shift switch, using the key switch, DOESN'T kill 12v power fed from the shift diode / stator to the fuse block or back side of the key switch. As long as that flywheel is turning, there's power fed to the complete system behind the key switch. In front of the key switch? To the battery? No. But I intended to use the key switch to open the circuit to the ignition to stop the engine running. (kill) If I implement the shift diode power behind the key switch, it will feed the ignition through the fuse block continuously, as long as the engine is running. I just need to implement a diode between the fuse block and shift switch for power from the key switch. That will keep the 12v fed from the shift diode from feeding it. If I wasn't using the shift switch to control the starting circuit (only start in neutral position) then it's simple. Since I am, it's still simple, I just need to be sure the diode in that location can handle the amp draw taken from the neutral solenoid AND the starter solenoid simultaneously. I will probably use the diode "acorn" that's already there in the stock control. That's it's purpose in the factory setup.

Wavrider, yeah, I've read about how to make that conversion to a conventional point broken / coil system. I also heard that it wears the points out quicker because of the voltage across them. Using a CDI box, (like factory) there is almost no voltage across the points. It's simply a ground break to trigger the CDI box, which is a condenser / amplifier (transistor induced) I am simply swapping out the factory amp to an after market one with a compatible after market coil. It's been done and documented to work great!

 

[jameskb2]

Re: 1972 electric shift

This seems to be getting out of hand. The blocking diode in the control keeps the alternator from feeding the ignition circuit after the key is turned off. If it were not for the blocking diode, the motor would keep running after you turn it off.

Indeed F_R, indeed....

 

[jameskb2]

Re: 1972 electric shift

Factory schematic of the shift circuit for troubleshooting.

Clearly shows the blocking diode to prevent back feed to the ignition switch.

 

[jay_merrill]

Re: 1972 electric shift

FR, this isn't getting out of hand - its just a discussion and we are simply trying to work through the electrical system on this motor to understand what it does. I don't think either one of us cares who is right or wrong, or partially right or wrong. From my own perspective, I find it to be a very intersting and informative topic for all parties.

 

[jay_merrill]

Re: 1972 electric shift

James, I think I see what you are saying and I now see the fault in my logic because moving the Ignition Switch to off probably doesn't doesn't open the circuit from the Ignition Switch to the Shift Switch. Instead, it opens "red wire circuit" from the Rectifier. That being the case, I think you both you and FR are right - there would be "back voltage" that would keep the motor running and there would be an open path back to the downstream side of the rectifier.

There is something curious about your diagram (which is from the manual) though. It appears to me that the diode symbol is backwards because it shows the arrow pointing into the "block bar" in the direction of the Shift Switch. If it were oriented that way, I believe it would block voltage from the Ignition Switch to the Shift Switch, not the other way around. I still think you are correct but this is puzzling. If anyone has any thoughts on the matter, I would love to hear them.

At any rate, I think we are getting this figured out and I think whatever we come up with will serve the folks who have these motors well.

 

[jameskb2]

Re: 1972 electric shift

Geeze Jay, I'm not getting anything done today!

(just kidding)

Nope, that diode symbol's orientation is correct. I noticed you had yours drawn backwards in your hand drawn design, but....I decided not to point that out.

Go ahead and do a little search for diode and or diode symbol. You'll see....

I'm done for now, gotta get out of here and produce.

I agree with what you said in regards to the thread. Maybe once we hash this out real good, and have a concrete, easily duplicated solution, they'll make us a sticky.

 

[ddaigle]

Re: 1972 electric shift

Its really not a big deal if the solenoids dont stay in nuetral when you turn the motor off. Mine dont and all you get is a clunk sound and the prop stops. There is not enough momentum to surge the boat or even move it.

 

[F_R]

Re: 1972 electric shift

FR, this isn't getting out of hand - its just a discussion and we are simply trying to work through the electrical system on this motor to understand what it does. I don't think either one of us cares who is right or wrong, or partially right or wrong. From my own perspective, I find it to be a very intersting and informative topic for all parties.

By out of hand, I meant that it is getting so lengthy and confusing that it's a chore to try to wade through it. And all just to hook up a simple shift switch.

Here's a diagram that shows it all in easy to understand form--if you understand electrical circuitry and the direction of current flow.
http://i155.photobucket.com/albums/...g197285hpSelectricfrverified.jpg?t=1206559059

 

[jameskb2]

Re: 1972 electric shift

Its really not a big deal if the solenoids dont stay in nuetral when you turn the motor off. Mine dont and all you get is a clunk sound and the prop stops. There is not enough momentum to surge the boat or even move it.

Yeah, you're probably right ddaigle, we're just trying to replicate the factory safety systems using different, easily obtainable components.

Inventing the wheel twice it appears. Most people would just throw up their hands and go buy a good used control, but I guess Jay and I aren't most people. Anal reverse engineers might fit.

F_R, thanks for that diagram. Very clear and nice to peruse. I have the factory diagram, but it's not as clean or uncluttered as that one. Sorry about the longevity of the thread. I agree we are getting a little carried away in "what about" land, but just making sure it's a good system. I'll probably start a new thread with a clean complete diagram, components and their part numbers plus where obtained, and a real picture of it in a mock up panel showing it all working. Or....not.... You just take for granted that you already understand this, and have a good solution with that toggle switch. I'm just figuring out how to do it different. Not better....just different.

Out the door I go.....(after one last look)

 

[jay_merrill]

Re: 1972 electric shift

LMAO .... I always did want some initials after my name .... A.R.E. ... yup, I like that!

The fact of the matter is that some people just want something to work and some want to know why that thing works. I am of the latter category most of the time and I think the value in that tendency is borne out here, because I think we have put our heads together to come up with something that is as close to the original setup as is possible. Given that these control units, and the parts in them, are going to become more and more scarce as time goes on, this is probably a good thing.

 

[jay_merrill]

Re: 1972 electric shift

Nope, that diode symbol's orientation is correct. I noticed you had yours drawn backwards in your hand drawn design, but....I decided not to point that out.

Actually, I wish you had because the goal here is not to be "right" or smarter than anyone else - its to learn and understand. I don't have a lot of ego about it all so I would have appreciated the pointer (as I do now) and would have been glad to know. I actually did double check a diagram but missed looking at the polarity in what I was studying.