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Ace 100 coil test results, good or bad?

Posted: Sun Mar 24, 2019 6:25 am
by Jeffbo1
My Ace 100 project has no spark. All wiring is connected correctly, lights, hi/low beam, and horn work, points are clean and set, yet no spark at the plug...I tested the coil with my volt/ohm meter and I am getting 2.2 ohm on the primary side and 9.2 (9200) on the secondary side. I feel these numbers are too low but perhaps I am wrong in this....Are these reading considered good or are they out of spec....any info would be appreciated as Im not finding coil data in my literature....many thanks!

Re: Ace 100 coil test results, good or bad?

Posted: Sun Mar 24, 2019 8:24 am
by Al Harpster
Your numbers seem a bit high, not low.

Page from Hodaka Workshop Manual attached.

Primary from .75 to 1.6 ohms

Secondary 4800 to 5000 ohms

There was a recent post on a battery attachment using 2 D cells to test the ignition system.

This two D cell test is the way to go to trouble shoot.

Can anybody in the forum find this and help this guy?

Re: Ace 100 coil test results, good or bad?

Posted: Sun Mar 24, 2019 8:27 am
by matt glascock
Have you taken the ignition switch completely out of the circuit? Disconnect the white contact block and retest. Then ground the spark plug base against the motor with the cap attached and kick it over. You should get a snappy spark. It could be something as simple as a spark plug cap making poor contact with the high tension lead. Wouldn't that be nice? Five dollar fix!

Re: Ace 100 coil test results, good or bad?

Posted: Sun Mar 24, 2019 8:38 am
by givergas
i was were you were on my first project, i was pulling my eyes out till i noticed i put the blue wire on the points on wrong moved it and big ole spark jump out. it was a good feeling. thats how it happened to me.....albert

Re: Ace 100 coil test results, good or bad?

Posted: Sun Mar 24, 2019 8:58 am
by Al Harpster
From previous post. Could not copy the picture. Will search for more..... Al

When you encounter a "no spark" condition, how can you go about isolating the problem? Well, here is what I do.

First, disconnect the main key switch (if applicable). The key switch, in the off position, grounds the ignition (black lead at the ignition coil). A defective switch can ground out this lead.

Next disconnect the kill switch (if applicable).

Still no spark? My next move is to test for spark using an external power source. Specifically 2 D cell batteries connected in series to provide 3 vdc. A little solder, jumper wire and an alligator clip (and of course Duct Tape). Here is a picture:
coil test.jpg

Re: Ace 100 coil test results, good or bad?

Posted: Sun Mar 24, 2019 9:01 am
by Al Harpster
Here's the step by step instructions

This test will confirm everything except the points and possibly an open exciting coil.

Step 1: Leave the main key switch and kill switch disconnected.

Step 2: Remove the spark plug and lay it on the cylinder while still connected to the coil. Make sure that the plug is grounded to the cylinder. Use a wire jumper if necessary.

Step 3: Insulate the points. Use a strip of paper or business card.

Step 4: Connect the negative lead of your 3vdc supply to the stator (ground).

Step 5: Tap or scratch the positive lead of your 3vdc supply at the points wire connection. Each tap will provide a spark at the spark plug.

If you are getting spark by tapping at the points wire, then connect your switches one at a time. Turn the key to the on position and re-test for spark. If spark is still good, then you have a bad set of points OR your exciting coil is open. It is the exciting coil that the 3vdc supply is mimicking. Note that a grounded exciting coil would keep test spark from happening.

If you do not get a spark from your points wire then move your tapping to the condenser. If nothing, then disconnect your terminal plug going to the ignition coil and tap the connection going to the ignition coil (black wire). If still nothing then move your power supply test leads (both positive and negative) clear up to the ignition coil itself.

Note that the only thing necessary to create spark is your ignition coil and spark plug (including the plug wire and cap) If you can not generate a spark by tapping black lead at the coil itself, then the problem is either the ignition coil, the plug wire, the plug cap or the spark plug itself.

If you find that you can generate spark at the coil but not with the stator connected, then standard isolation trouble shooting applies. The best reference that I have found is found beginning on page 71 of the Official Hodaka Workshop Manual (Wombat and Combat Wombat).

I hope that this information is found useful. You can verify an ignition coil on the bench with just the coil, spark plug and the 3vdc battery pack. Use test leads to tie your spark plug ground to your coil ground and the negative lead of your power source. Pretty simple and effective!
Dale

Re: Ace 100 coil test results, good or bad?

Posted: Sun Mar 24, 2019 5:56 pm
by Jeffbo1
Many thanks to all for the helpful replies, I will try the tests you have suggested....I have no kill switch on the bike and the ignition switch is new....I will retest by separating the white junction block and go from there....many thanks again!

Re: Ace 100 coil test results, good or bad?

Posted: Sun Mar 24, 2019 6:23 pm
by taber hodaka
My have used the battery to energize the system for years, when I was the hodaka dealer in the 60's. Used properly it also checked the points. I used a low amp 6 volt trickle charger or a 6 volt lantern battery with plus and minus connectors on top.--------------- Clarence