Wisconsin VH4D Magneto!!!

[Vincent C]

Hello all!
Been on this topic prior and just cannot get a resolve. she was running fine than stopped. Changed out the condenser and she fired up but only on 3 cylinders.

Now heres the deal, someone must have opened up the magneto because the firing order was 3-1-2-4 CW. three being the upper right. i know the order should be 1-3-4-2 but it ran fine the other way.

We have tried every combination of putting the magneto back in following the books instructions. #1 piston on compression at Fly at 12 noon and the magneto's gear hatch at the bottom of the inspection hole on the case.

then we hand fired the magneto to confirm it was firing #1 (in this case bottom right #3) 2,4,1, clockwise. Nothing, one tooth up and one tooth down, nothing. We tried all the same at the mark at 10 oclock and nothing also.

I know when the magneto is opened you cause a can of worms. There must be a logical explanation with something going on with the impulse coupling that is just not understood.

Any magicians out there know the answer to my hair pull?"

 

[Billy Shafer]

Check over at Smokestak. We have a section over their that covers
that engine.

 

[teddy52food]

How many impulses do you get in one turn of the mag.? 2 or 4?

 

[wore out]

Some Wisconsins use an odd fire magneto, meaning the cam lobes are not all equidistant from each other. If yours is one of those the mag has to be timed to the engine EXACTLY as specified in the manual for that engine.

Or, there COULD be a mis-match of engine and mag, an even fire mag on an odd-fire engine or an odd fire mag on an even fire engine. (This related to variations in the arrangement of the crankshaft throws over the long period of time the engines were in production, (and a camshaft to match).

Also, as to the alleged 3-1-2-4 firing order, convention is to start with #1, and in doing that your 3-1-2-4 firing order simply becomes 1-2-4-3, two ways of writing the SAME thing.

Also, IIRC, some Wisconsins used a mag without a half-time reduction on the rotor, meaning that the sparkplugs were fired twice per combustion event. LOTS of variations and possible chances for error.

 

[Tramway Guy]

For the record, the VH4D is an even-fire engine. If you put a mag from an odd-fire engine on it, it would be extremely difficult to
get it to run properly.

 

[Farmboy 81]

If it was me and had access to a half
speed distributor I'm not so sure that I wouldn't seriously be considering swapping it into that engine with electronic ignition in it. I've got one that has a mag and the other 6 have a distributor with electronic ignition. The one with the mag gives regular problems while the electronic converted distributors give no problems and have more power. Just a suggestion FWIW. I know this dosent answer your initial question. Points and condenser quality has gotten very questionable and has to be timed perfectly for it to work with any satisfaction.

 

[rustred]

I just read this 3 times and am not following what u are doing!
Does the engine start? Dont start? What is going on? Is this
the same mag? Why was mag taken off? Plus u have not said
that u even verified it was timed correctly. We are not
magicians.

 

[Vincent C]

(quoted from post at 20:37:47 03/20/21) I just read this 3 times and am not following what u are doing!
Does the engine start? Dont start? What is going on? Is this
the same mag? Why was mag taken off? Plus u have not said
that u even verified it was timed correctly. We are not
magicians.

ood morning, Same mag pulled because condesor quit. at one point ran on 3 cylinders. Timed correctly? there is talk of timing light timing yet there is no adjustment at the magneto. This is a morese fairbanks unit.

 

[Vincent C]

(quoted from post at 20:11:54 03/20/21) If it was me and had access to a half
speed distributor I'm not so sure that I wouldn't seriously be considering swapping it into that engine with electronic ignition in it. I've got one that has a mag and the other 6 have a distributor with electronic ignition. The one with the mag gives regular problems while the electronic converted distributors give no problems and have more power. Just a suggestion FWIW. I know this dosent answer your initial question. Points and condenser quality has gotten very questionable and has to be timed perfectly for it to work with any satisfaction.

yes I agree as this was my first move but Pertronics only makes it for one unit and i cannot tell what unit i have. I have another VH with electronic and it runs like a charm. So i can find a different half speed distributor in place of this magneto?

 

[Vincent C]

Same magneto that originally ran.

 

[teddy52food]

If you answer my ? I may be able to help.

 

[Duner Wi]

Take a look at this wiring diagram. I believe you have a half speed magneto which runs opposite direction from a full speed odd fire engine. I believe all VH4D had 1/2 speed distributors or magnetos.
https://wiringall.com/wisconsin-motor-vh4d-firing-order-diagram.html

 

[Duner Wi]

This article explains the odd fire full speed magneto VE4 and VF4 really well.
https://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=implment&th=191346