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???how To Check A Condensor And Ignition Coil With A Meter??


namor1's Avatar
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12-21-07, 10:38 AM   #1  
???how To Check A Condensor And Ignition Coil With A Meter??

Just got the flywheel off a Tecumseh H35 from an Ariens model 932001 2.7 HP snowblower.

I'd like to check with a multi-meter if the ingintion coil and condenser are working. Any ideas on this please?

The condensor has a metal ground welded to the metal casing and the other end is a black wire crimped to one of 2 wires from the ignition coil

The ingintion coil has the spak plug cable and also the mentioned 2 thin black wires.

I tried a multi-meter set at DC VOlTS at 200mv and with one test lead on the condenser casing and the other lead on the condesner's black lead ,the voltage is increasing. By reversing the leads the condenser being a capacitor is discharging the voltage,so I think the condenser is ok.

As for the ignition coil I tried an ohm test with one test lead on the spark plug wire and the other test lead on one of the ignition coils black wires and get open circuit. Same open circuit with one lead on the spark-plug wire and the other test lead on the other ignition coil wire.

Same open circuit for the 2 small ignition coil wires.


Thanks

Gus

 
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cheese's Avatar
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12-21-07, 04:34 PM   #2  
Check the resistance readings from the wires to the metal laminations of the armature on the coil. This is the reading you're looking for, but the value varies widely. I don't recall the range you're looking to fall into, but I can check a coil and tell you the readings I get, or post your results and we can compare.

On the capacitor, use the ohm setting on the meter to charge the capacitor. As you hold the leads onto the cap, the resistance should steadily and rapidly increase. Once it is charged, use the dc volt setting to observe the discharge. The voltage should drop steadily and rapidly. This doesn't prove beyond a doubt that the cap is good, but it's good enough to bet on.

During all this, do not remove the coil bracket. If it is removed, you will have to go through a more involved process of setting it again...using special tools. I hope this info hasn't come too late.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
namor1's Avatar
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12-21-07, 07:57 PM   #3  
Thanks chees ,got a sparka and good engine compression

Posted By: cheese Check the resistance readings from the wires to the metal laminations of the armature on the coil. This is the reading you're looking for, but the value varies widely. I don't recall the range you're looking to fall into, but I can check a coil and tell you the readings I get, or post your results and we can compare.

On the capacitor, use the ohm setting on the meter to charge the capacitor. As you hold the leads onto the cap, the resistance should steadily and rapidly increase. Once it is charged, use the dc volt setting to observe the discharge. The voltage should drop steadily and rapidly. This doesn't prove beyond a doubt that the cap is good, but it's good enough to bet on.

During all this, do not remove the coil bracket. If it is removed, you will have to go through a more involved process of setting it again...using special tools. I hope this info hasn't come too late.


Thanks cheese about how to check these 2 issues. The condenser is taking and discharging low voltage. The ignition coil high voltage wire (spark plug Wire) to ground ohmage was very high ,it read infinity on my meter.

The ohmage from the 2 other thin black ignition coil wires to ground were low about 160 ohms respectively. One of these wires is just grounded to the chassis along with the metal casing of the condenser and the other is crimped on to the condeser wire.

I also regapped the cam point to .020 and lightly sand papered all connector metal surfaces, the 3 ignition coil ends,the inside of the flywheel , the 2 point gap surfaces, and scraped the inside of the spark plug cap. End result is very good spark. The machine has a new life.

I just have to hunt down a dealer for some carb parts,;this Tecumseh H35 carb has a diaphram and a main jet with a rubber oriifice for the needle to move about;its not as good as the float/bowl carb versions.


thanks again

Gus
Toronto Ontario Canada

 
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12-21-07, 09:27 PM   #4  
Go to this link, disreguard the part about outboards. It has the info about condensers about midway down. Have a good one. Geo
http://assets.fluke.com/appnotes/ele...r/B0271b_u.pdf

 
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12-22-07, 07:50 AM   #5  
nice link, Thanke geogrubb

Posted By: geogrubb Go to this link, disreguard the part about outboards. It has the info about condensers about midway down. Have a good one. Geo
http://assets.fluke.com/appnotes/ele...r/B0271b_u.pdf

Great link thanks geogrubb, got the diagnosis for condensers down pat. Good info how an ignition coil works and to expect an ohmage of between 2k and 15 k from the spark pug lead to ground which is the resistance of the secondary coil plus the spark plug lead. Anything over this ohmage like infinity poses an open circuit in the secondary or the secondary to the spark plug boot.

Happy holidays
Gus

 
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