Back To The No Spark Issue

[John Gragg]

So I’m back in the garage working toward solving my no spark issue. Did a lot of reading last night on old and current posts regarding the magneto systems, coils, condensers, points, etc.

I pulled off the armature plate today (after pulling the rotor) and the rotor pulled very easily. I almost didn’t need a puller. Is that normal?

Inspection of the plate and rotor show the rotor was rubbing on the oiler. (See Pics).

Not being an electrician and struggling with the theory of magneto ignition systems (yes, I have watched a ton of videos and still struggle) I am questioning if the oiler and the rotor being in contact is (at least part of) my problem? I’ve gone over the parts diagrams 20 times now and I can’t figure out why/how the magnet is touching. There is/was a copper washer underneath the flywheel, on top of the rotor (magnet). Is that washer supposed to be somewhere else?

As a reminder – I have one coil that is known to be good, the other is junk. Condensers both check out at .185uF for one and .205uF for the other. Points have been cleaned up and polished. I checked the points with the condensers disconnected and there is no continuity between the point frame and the wiring rail the condensers connect to.

Both plug wires check out with very low ohms (one at zero, the other at .2). Zero continuity between the plug wires and the plate (no ground shorts from the wires).

Edit: Ignore the arrow in the pic showing ‘damage’ from the rotor to the armature plate. Not true, just a rough casting right there.

Thoughts?

Thanks,

Best Regards,

John Gragg
RIverside, CA

Just starting in the hobby, please be patient.

48 Sea King 5hp GG9014A. Sold
49 Sea King 5hp GG9014A
48 Johnson TD20. Sold
49 Johnson TD20. Sold
54 Johnson QD15. Sold
55 Johnson CD12. Sold
57 Johnson RJE-19M
57 Johnson RDE-19

[joecb]

OK John, I have to admit that I’ve lost track of what motor we are working on here. As for the rotor, it should not be rubbing on anything. From what I gather from your description and pix, either the mag plate is not down in proper position, or the rotor is too low. The magnets in the rotor should be in line ( up and down) with the iron heals of the coil armature.

And yes, the rotor should come off of the crankshaft easily, not a tight fit… also there is a key on the crankshaft ? yes? to fit in the rotor key-way.

Joe B

PS, what you are calling a “slinger” is actually a felt wiper. Lightly oiled felt to keep the breaker point cam surface clean and lightly lubricated.

[John Gragg]

Joe,

Sorry – Did it again.

Monkey Wards ’49 5hp.

Both keyways (rotor and flywheel) in place on the crank. I thought I read the description in the parts book, but looking at it again it is simply called an oiler assembly. Thanks.

After sending the message out I put the plate back on and seated in down on the crank fully. Tightened it down (learning here) and realized it has to move for advance/retard, so I loosened it up a bit. Cleaned up the crank and rotor and put the rotor in place. It fits just fine, no interference with the oiler.

My guess? At one time the plate was loose enough to cause the scarring but fixed soon after? Can’t be sure, but that is my guess for now. I would think there would be much more damage to the oiler if it had been that way for a long time.

Thanks for the advice – Gonna keep plugging tomorrow.

Best Regards,

 

John Gragg
RIverside, CA

Just starting in the hobby, please be patient.

48 Sea King 5hp GG9014A. Sold
49 Sea King 5hp GG9014A
48 Johnson TD20. Sold
49 Johnson TD20. Sold
54 Johnson QD15. Sold
55 Johnson CD12. Sold
57 Johnson RJE-19M
57 Johnson RDE-19

[HARRY D. NICHOLSON]

After cleaning, you need to prove that the points are making and breaking contact electrically. To test their contact, remove all wires attached to the brass bar on the points assembly (coil wire and condenser wire), then touch one meter wire to ground (mag plate) and touch the other meter wire to the brass bar that held the coil & condenser wires. Then operate the fiber push bar in and out to test contact continuity on your meter. Sometimes clean looking points are dirty/oily.

[John Gragg]

Thx Harry,

I don’t remember who, but somewhere along the line I got my hands on a tutorial that says the same thing. I have already tested resistance and I get zero with the points contacted and off the scale (open) when the points are open.

I polished the points starting with 800 wet/dry sandpaper with pb blaster as a lubricant. Then to 1500 with pb as well. Let the piece glide over the sandpaper very lightly and used a hacksaw blade as a backer to buff the point on the breaker frame. Cleaned with carb cleaner to be sure no oily residue.

They are very well polished but I think I’m going to hit them with 2000 tomorrow for a ‘windex’ shine. LOL

Best Regards

John Gragg
RIverside, CA

Just starting in the hobby, please be patient.

48 Sea King 5hp GG9014A. Sold
49 Sea King 5hp GG9014A
48 Johnson TD20. Sold
49 Johnson TD20. Sold
54 Johnson QD15. Sold
55 Johnson CD12. Sold
57 Johnson RJE-19M
57 Johnson RDE-19

1 user thanked author for this post.

frankr

[frankr]

I don’t know why you don’t have spark yet.  Everything seems to be ok according to what you’ve written.  My inquisitive mind asks if the magnet/rotor was destroyed by friction/overheating from the rubbing.  But my brain says “nah”.  Hmmmm, wonder if somebody destroyed it in a failed magnet recharging attempt?  But not wanting to send you on a false wild goose chase.

1 user thanked author for this post.

John Gragg

[joecb]

As frank sayz , “nah” … but a quicky test for the magnetism… suspend a flat blade screwdriver blade near the magnet, the magnet should draw in the steel blade from about 3/4 inch away.

And at the risk of covering old ground… how do you know that the coil is good? how was it tested? If just a simple resistance test using a VOM, that may not be good enough. I recently had a coil that tested OK with the VOM but would not produce a spark on the Mertronic, apparently there was an internal short within the secondary windings.

Joe B

1 user thanked author for this post.

John Gragg

[HARRY D. NICHOLSON]

I wouldn’t use any kind of lube/chemical on the points. That may leave a film that is non-conductive. After sanding to a near-mirror finish, I use “Electronic Contact Cleaner” only, then clean paper pulled through the points.  Some paper is no good from ingredients in it.

You need sufficient RPMs to test for spark and a good grounded spark plug and plug wire with no cracks in it where arcing could occur.

1 user thanked author for this post.

John Gragg

[jeff-register]

Joe,

I had the same problem with a secondary winding. Reading very hi resistance and I found a carbon gap where it had been run with plug wire off & arced to the plate & had  a little pin sized hole in the outer covering where it arced to ground.

Do you have all rhe spacers required on the points to points arm? Little nylon insert & washers. No telling who has been in there before you! Check the solderless wire connections for hi resistance, I’ve found that before wire to connector. Don’t assume any connection is good. I had a magneto that was missing real bad. I had cleaned the contact surfaces very well & lubed lightly & one coil was reversing current to the other coil turning the points gold they got so hot. Hi voltage does weird things. Added a ground, bonding wire from mag plate  to block & solved it. With cleaning & relubing it had very high resistance between the block & mag plate. Check every connection even if it is a mechicnal. The figure 8 on the ohms scale equals infinate or no connection. Hope this helps! I wonder if your rotor is running true? put it on /7 rotate  the crankshaft & clearances between both laminations & record, rotate 180 degrees & recheck. That’s one I’ve learned from a service manual, clearances are very tight for a good spark. Check capacitors on an magneto analaiser, VOM meters check  face not working values. That would kill good sspark.If they are old the dielectric value is bad, insulation value, sorry! Caps are a sandwhich of conductor/insulator/conductoe & akk you need is a pin hole in the insulator for failure. enough out of me! Don’t give  up you WILL find the problem!!

[Tubs]

If someone hasn’t suggested this already, rotate the motor till
one set of points just open. Then check the cylinder that the
coil that set of points go to. If the piston is not near the top
of the cylinder the coils are wired to the wrong points.
Tubs

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

[Author]

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