Points assembly and Magneto Puch Maxi

I have a question about the points on my 1976 Puch Maxi.

This is a new bike to me, and I am working out the problems.

First is that there is no juice coming from the magneto.

I have the flywheel off so I can check the points and clean up the stator.

I am checking to see if the points are correctly installed. Sometimes the sequence of the washers gets mixed up, causing a conductivity problem. Since I did not put them in, I want to start there.

I have an Ohm meter to test conductivity between the points being closed and open. Where should I be hooking the leads up to get an idea about this. I realize that the points interrupt the flow of current causing the field to collapse and discharge to the coil. I'm just wondering how I can test that this is actually happening with my multimeter.

Thanks,

Matt.

Re: Points assembly and Magneto Puch Maxi

One of the point contacts is always grounded.

The other contact has a wire that splits off and goes to the condenser and ignition coil. If there's any continuity between the condensor wire and ground when the point contacts are open, something aint right.. perhaps an insulating washer is misplaced as you suggested.

Re: Points assembly and Magneto Puch Maxi

Somethin aint right then!

I have continuity from the base of the points to the open side.

I think that there should be continuity when they are closed, but when they are open there should be none.

I have tested with a lead to either side of the points and to the blue wire. We have continuity no matter what.

Can you give me a picture of the points and how the washers should be spaced.

Thanks.

Matt.

P.S. I live in Maine, and our season is short so I am loosing VALUABLE time here!!!!

Re: Points assembly and Magneto Puch Maxi

opps.. i shoulda mentioned..

Before testing, disconnect the condenser-coil wire from the points. Isolate that side of the points.. Otherwise there will be some continuity .. Ohms will be a measure of the ignition coil's primary to ground and the magneto stator ignition coil to ground..

Re: Points assembly and Magneto Puch Maxi

heh.. you should be thankful you get ANY sunshine up there :)

ok.. the point contact is connected to both the stator winding (to ground ) and the ignition coil primary (to ground). So, the point contact wire should be isolated or disconnected. When isolated from everything that side of the points should not ground.

Also check the condenser wire to be sure it's not internally shorted (to ground).

:

But before going down this road, you might save some time by hooking things up so a minimum of wiring is used and then test for spark.

Eliminate potential wiring problems on the frame's wiring harness (faulty switches, connections, bad insulation, etc) by minimizing ignition wiring.

Mentally substitute a magneto for the battery in this photo..

Re: Points assembly and Magneto Puch Maxi

I checked the set up, and I have 2 wires coming off the points.

One is blue which goes to the terminal coil

The other is Black which goes to the condenser.

If I check the continuity between the condender body and the black wire, I get continuity. Does this mean the condenser is fried?

If I disconnect the 2 wires from the points, and hook the leads up to either side of the points, I get the break in continuity once I open the points. But after I hook up the 2 wires, I get continuous continuity. It seems the weak link is the condenser since it grounds the connection.

Do you think I am right?

Matt

Re: Points assembly and Magneto Puch Maxi

I checked the set up, and I have 2 wires coming off the points.

One is blue which goes to the terminal coil

The other is Black which goes to the condenser.

If I check the continuity between the condender body and the black wire, I get continuity. Does this mean the condenser is fried?

If I disconnect the 2 wires from the points, and hook the leads up to either side of the points, I get the break in continuity once I open the points. But after I hook up the 2 wires, I get continuous continuity. It seems the weak link is the condenser since it grounds the connection.

Do you think I am right?

Re: Points assembly and Magneto Puch Maxi

_ If I check the continuity between the condender body and the black wire, I get continuity. Does this mean the condenser is fried_

The installed condenser body is grounded to the engine. If it's wire is not disconnected but is somehow also grounded through some other wire connection, you'll see some continuity.

But if the condenser is removed from the engine or if it's wire is isolated and disconnected, there should be no continuity between the condenser wire and the condenser metal can or engine ground.

in other words, a condenser sitting on the work bench shouldn't show continuity through it's wire to it's metal can.

------

Assuming NO other wires (coil connections, etc) are causing continuity between the open points contacts and ground, and assuming the condenser is connected as normal, the condenser could be internally shorted and causing continuity when there should be none.

Re: Points assembly and Magneto Puch Maxi

The points are connected to the ignition coil and the stator ignition coil. They are also somehow connected to the Kill switch (and Ignition switch if there is one).

Those switches would ground the points and kill spark when activated (or ignition switch deactivated). Make sure the switch(es) wiring is correct and in good shape and is not grounding the points when they shouldn't..

:

I'm not that familiar with your bike .. but i know that some bikes are dependent on weird things to get spark.

A broken tail lamp element or disconnected horn could prevent spark (safety reasons).. Some bikes have fork-locks that include a "kill" switch function. So, although the ignition components themselves could be ok, something unrelated could prevent spark.

This is why i suggested minimizing wiring by disconnecting the engine from the frame's wiring when testing the ignition.

Re: Points assembly and Magneto Puch Maxi

See # 4 and 5 to see hoow to check points opening with a multimeter. https://www.mopedarmy.com/forums/discuss/read.php?f=1&i=202066&t=188637 Jim.

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