evinrude ski twin timing question

[1946Zephyr]

Re: evinrude ski twin timing question

Hmmm, that could be your issue then. Leaks and/or restrictions in your fuel system will cause the issues that you're having. If you go buy a new one I wouldn't throw your old one out. It'll be good to put in your tackle box as a back up.

 

[gwoloshyn]

Re: evinrude ski twin timing question

I figured I would continue on this thread rather than starting a new one with my updated situation on this motor. The culprit for the idle sneeze was a clogged high speed passage in the float bowl that I missed while rebuilding the carb. That problem is fixed.

Now, I'm trying to get the timing link and sync correct. I've followed all the instructions in this thread and got everything close to being right. The problem is, when I advance the throttle to wide open, it will not retract back to close but instead snap back to close. There is a problem with my throttle return spring. It seems strong, and there are no restrictions, so I'm wondering whats going on. Does the carburetors throttle butterfly need to be perfectly horizontal for everything to be setup correctly? If I adjust my linkage collar, I can get it so the throttle retracts back on its own, but the throttle butterfly isn't close to wide open.

 

[jimmbo]

Re: evinrude ski twin timing question

That spring is not a throttle return spring, it is there to allow further movement of the linkage to open the carb butterfly once the armature plate reaches full advance. looking at the picture of the armature plate, it might be the angle of the pic but I can't see the cam for the points to rub on.

 

[gwoloshyn]

Re: evinrude ski twin timing question

Is the armature plate supposed to spring back to its other stop position on its own? Right now, the spark plug wires are stopping it from moving all the way back and that's whats keeping it running.

I'm SO FRUSTRATED WITH THIS MOTOR AND NEED SOME SERIOUS HELP.

 

[jimmbo]

Re: evinrude ski twin timing question

When you retard the throttle the spring should be releasing it's energy as the throttle butterfly closes, then after the carb has closed and the the spring has fully uncompressed, further retarding of the throttle should have the armature plate moving retarding the spark. If the plug wires are interfering with free movement msybe they need rerouting or repositioning as to allow movement.

 

[gwoloshyn]

Re: evinrude ski twin timing question

The picture below is the position of the armature plate where the motor sits and idles. Does it look right OR does the armature plate have to be against the stop? The link and sync was done correctly so this should be the right way. The thing I don't understand is that my spark plug wires, as you can see, are acting as a stop from preventing the armature plate from moving further, stalling out the motor from an idle. Right now, I am adjusting the motor to idle by moving my spark plug wire position!

 

[jimmbo]

Re: evinrude ski twin timing question

Looking at the picture you have plenty of spark plug wire to pull forward of the guide,loom to create slack so the armature plate can rotate. Retard the spark enough and the engine will quit. You actual idle stop is located a little bit below the bottom of the pic.

 

[gwoloshyn]

Re: evinrude ski twin timing question

Yes, if I move the armature back any further the engine will quit. So, is this the correct position for the armature plate at idle?

 

[lindy46]

Re: evinrude ski twin timing question

Those wires look to be too tight to allow the armature plate to hit the stop, which is located beneath the flywheel on the back side of the powerhead. As suggested, pull them a little more forward through the guide.

 

[jimmbo]

Re: evinrude ski twin timing question

Yes, if I move the armature back any further the engine will quit. So, is this the correct position for the armature plate at idle?

Retarding the timing is the only way to slow the engine down, if those wires are too tight the armature will not be able to rotate any further. there is no prelocated correct position for idle, when the idle speed is at spec with the idle mix correct then one could say the armature plate is in the correct position. Also there is no idle stop for the armature plate. The idle stop is located on the outside of the engine on the vertical throttle shaft. The only stop for the armature plate is max advance.

 

[gwoloshyn]

Re: evinrude ski twin timing question

The only stop for the armature plate is max advance.

Thanks. That is what I wanted to know. The wires DO have enough slack for the armature plate to reach full advance. I was wondering if there was a position it had to reach going the opposite direction.

The problem I'm still having is when I open the throttle WOT then try to throttle back down, it snaps back down instead of slowly moving with my control. It's something to do with that spring that I cannot figure out. If my link and sync is where it should be, then why is my throttle plate snapping close like that?

 

[lindy46]

Re: evinrude ski twin timing question

The problem is, when I advance the throttle to wide open, it will not retract back to close but instead snap back to close. There is a problem with my throttle return spring. It seems strong, and there are no restrictions, so I'm wondering whats going on. Does the carburetors throttle butterfly need to be perfectly horizontal for everything to be setup correctly? If I adjust my linkage collar, I can get it so the throttle retracts back on its own, but the throttle butterfly isn't close to wide open.

View attachment 154280View attachment 154281

That spring will sort of "snap" the cam follow roller back to contacting the cam when you retard the throttle. The spring slides in the groove and flips back and forth when you advance or retard the throttle, thus causing the "snapping" action. The collar on the linkage rod needs to be adjusted so the throttle butterfly is wide open when the throttle is fully advanced.

 

[jimmbo]

Re: evinrude ski twin timing question

does the armature plate move smoothly by itself when unhooked from the throttle linkage, or is it sticking and binding?

 

[jimmbo]

Re: evinrude ski twin timing question

The collar on the linkage rod needs to be adjusted so the throttle butterfly is wide open when the throttle is fully advanced.

The collar is adjusted so it just makes contact with the movable stop, actually it is supposed to have 1/32" clearance, when the armature is held against its stop

 

[gwoloshyn]

Re: evinrude ski twin timing question

does the armature plate move smoothly by itself when unhooked from the throttle linkage, or is it sticking and binding?

Yes it moves fairly smooth, I had taken it off when I replaced my ignition parts and re-greased it. When I retard my throttle back down to idle, the armature plate moves back, but not to a certain position, just back enough to return it to an idle speed. I have the stop at full advance which it touches and then my collar moves to open up the carb however I do not have a point at which the armature plate can 'stop' going in the other direction.

If your saying this 'snap' action is correct, then when I'm at WOT and I want to throttle down, the throttle plate will snap to closed? That doesn't make sense.

Please bare with me, hopefully you have an idea of what I'm trying to describe here.

 

[gwoloshyn]

Re: evinrude ski twin timing question

That spring will sort of "snap" the cam follow roller back to contacting the cam when you retard the throttle. The spring slides in the groove and flips back and forth when you advance or retard the throttle, thus causing the "snapping" action. The collar on the linkage rod needs to be adjusted so the throttle butterfly is wide open when the throttle is fully advanced.

So it is normal when I throttle down for my throttle plate to snap to a closed position?

 

[gwoloshyn]

Re: evinrude ski twin timing question

Bump

 

[lindy46]

Re: evinrude ski twin timing question

When you reduce speed, the cam follower should return to contacting the cam at about 3/4 speed as the spring releases. That is the "fuel economy" position. The throttle butterfly should still be partially open at that position. Is the cam adjusted properly? You may have to loosen it and adjust it so the butterfly just starts to open when the pointer just to the left of the cam follower roller points to the mark on the cam.

 

[gwoloshyn]

Re: evinrude ski twin timing question

Thanks. The cam and roller are synced properly so the throttle plate just begins to open as the roller passes the mark. When I reduce speed, the throttle plate snaps back to just barely open and the cam roller is resting on the cam in this fuel saving position.

It just doesn't seem correct for the carburetor to snap closed but ill try it out and see.

 

[lindy46]

Re: evinrude ski twin timing question

On that particular motor, there is a pointer to the left of the roller, and the throttle butterfly should just start to open when the pointer hits the cam mark, NOT the roller. If it doesn't start opening until the roller hits the mark, synchronization will be off as the butterfly will be opening late. and yes, it will be barely open, if at all, once the follower comes back in contact with the cam.

When you hook up your throttle cable, the "snap" will be less noticeable when using the remote.