Flywheel magneto draggs maggplate with it

Hi, I recently replaced the maggplate components (setpoints and condensers) and the coils on my johnson 1975 25 hp (25R75B) and also cleaned all the maggplate and the rings under it.

The problem im having now is that the magnets on the flywheel "seems to be to strong" and they drag the maggplate with it as it rotates. Maggplate and flywheel are not touching eachother is just the strenght of the magnets moving the maggplate.

The motor runs great, i manage to run it by locking the throttle link that coneccts the maggplate to the throttle, but as soon as i remove lock, the maggplate rotates and engine dies.

Adjust the coils so that they clear the flywheel magnets.

see pic fingernail tip should not snag going up or down where the little arrow point (coil-boss junction)

racerone said:

Adjust the coils so that they clear the flywheel magnets.

Click to expand...

There is only one coil under the flywheeel and is the charge coil, and it is clear and flush where it is suposed to be. The ignition coils are back near the sparkplugs.

There is no marks on the coil that suggest the flywheel is touching it. And from what i can see there is no way to take the coil closer to the cam to get it away from the magnets

picture above was just a ref. to align things

does your fingernail snag or not .....going up-down the coil lamination face ?

if yes you can expand the coil's bolt hole with a drill bit to allow you to back away from the rotating FW .

Magnets are doing what they do best.---Just run the motor.

Armature plat lareral play can cause coil/magnet rubbing even when coils/sensor are aligned on plate properly.. I found this by Joe Reeves:

(Magneto Armature Plate)
(J. Reeves)

If the armature plate has a a loose fitting, wobbling motion (the plate that the points, coils etc are attached to), it is usually caused by a slightly worn support ring. This allows the point setting to change erratically as the armature plate turns.

The cure is to remove the armature plate so that the support which is attached to the powerhead with 4 screws is visible. Then, with a screwdriver and hammer, or some tool of your choosing, and looking straight down at the support ring, make an indentation at what would be called the 12, 3, 6, and 9 O'clock positions. Install the armature plate and check for a smooth turning wobble free movement.

You may need to do that procedure a few times to obtain the proper fit (not too tight, not too loose), but it's worth the effort.

Use a small amount of anti corrosive grease between the aluminum ring and the brass support plate and also on the brass bushing of the armature plate when all is well.

Crosbyman said:

see pic fingernail tip should not snag going up or down where the little arrow point (coil-boss junction)

Click to expand...

I was able to fix this, thanks guys!

It turns out that the charge coil was not perfectly aligned to the marks on the magplate, i missed this during the assembly, moved the coil like 2 mm away from the magnets and aligned to the marks on the magplate and it fixed the problem

thanks for the feedback !