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Yamaha yz 400 how do i test the source coil,with a multi meter,it only has one wire coming from it?

Is the pulse coil grounded to the plate?and does the source coil only have one wire?ibefore i got the magneto flywheel off i shot some cleaner in there ,and when it was wet ,i got spark,when it dried ,no spark.

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Posted on Jan 02, 2017

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SOURCE: no spark

remove the ignition coil from the bike.

The primary winding should have a resistance between 2 and 6 ohms
The secondary winding should have a resistance between 19Kohm and 40Kohm.

In fact the primary must have less than a 50ohm, but there MUST be a resistance.
The secondary should have a resistance of 15.000Ohms and more, but there MUST be a continuity.

Posted on Apr 02, 2009

  • 1 Answer

SOURCE: ignition

I hope this diagram helps, it did me!


Posted on Jul 24, 2009

  • 1 Answer

SOURCE: 19-95 KLF300 ATV Kawasaki 4x4 no spark put new ignitor unit on.

i ******* hate my kawasaki kdx 125 1992 there is no spark and i dont no wot it needs ive bought a cdi for it an it wernt that and i bought a new coil and it wernt that either could anyone help me please

Posted on Sep 11, 2009

ollie reece
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SOURCE: Bike wont start

hi buddy to check the magneto just find the wires from the magneto and test them out with a volt metre if you have nothing there must be the stator plate gone get back to me buddy

Posted on Sep 20, 2009

  • 414 Answers

SOURCE: rm125 1999 no spark

what comes out of CDI box? if you have it going in it is rectified and more will come out. If not change CDI

Posted on Mar 07, 2010

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1 Answer

3.5 Briggs ,new coil ,ground wire unhooked,no spark

Re loosen the magneto place business card between mag. And flywheel retighten mag mounting screws remove business card shine up flywheel with sand paper with the mag off the motor clean rust off flywheel before remounting mag with business card.

Apr 25, 2017 | Briggs Garden

2 Answers

Will the fly wheel cause no spark

Be sure the magneto is gapped properly. A sheared flywheel key will cause timing issues but not eliminate spark. Either you have purchased faulty parts or spark is not your problem. Remove the ground wire from the coil, be sure you have tightened the flywheel nut properly, spray some carb cleaner in the carb and try to start. If it starts on the prime then you have spark and its a fuel problem. If it starts with the ground wire disconnected but not when the wire is connected then there is faulty wiring or a bad switch.

Jul 15, 2014 | Stihl Garden

3 Answers

Why my 6.5 craftman eager-1 has no spark

Check the engine stop wire where it connects to the carb mounting plate. make sure it is not shorted to ground. Remove the top cover from the engine and check the flywheel to magneto air gap, it should be about .020 of an inch, this is about the thickness of a matchbook cover. Also check the spark plug wire and the connections, make sure they are clean and tight. The magneto is the y shaped piece behind the flywheel. Remove the flywheel holdown nut and washer and make sure the notch in the flywheel and in the crankshaft are across from each other. If they are not, you will need to remove the flywheel, and replace the aluminum key that goes there. The notches need to be aligned for the ignition timing to be correct. I hope this helps, good luck. Dan

May 23, 2014 | Briggs & Stratton Briggs Stratton...

1 Answer

I cannot get any spark. The plug is brand new.

Just in case you are unaware, first I want to mention that if you are trying to affirm spark by looking at the plug while it is out, the plug must be held firmly against the engine so the spark has a ground return path. If there is nowhere for the electrical pulse to go, the spark that will be there -- if any at all -- will be so small that you can't see it. Use a well insulated pair of channel-lock type pliers and hold that plug firmly against a paint-free, metal surface of the engine.

If there is no spark: The spark is generated with a device attached to the inside of the flywheel -- the Magneto. This is actually two pieces, a permanent magnet and a coil pack. The magnet flying past the coil pack generates a pulse of electricity. There should be a single wire comming out from behind the flywheel. This wire is coming from the Magneto and is going to the spark plug. First, however, it will most likely goes to another small canister-looking thing called a Condenser.

Follow the wire coming out from behind the flywheel. See if you can just follow it with your eyes and be sure nothing has been accidentally disconnect (us sophisticated mechanics call this "eye-balling").

In the event that there is no spark, and the wires are all in place, the most likely circumstance is that the Magnet 1/2 of the Magneto has come loose and is no longer attached to the flywheel. To fix, you have to remove the flywheel. Generally there is one large nut holding the flywheel onto the end of engine shaft. This said, it is possible (but not probable) that the Condenser is bad.

So, if you choose to tackle the job, you should probably take the condenser to a small engine parts center and have them test it before you remove the fly wheel.

I hope this helps you. If it does, please take a sec to rate me. Thanks!

Mar 24, 2012 | Briggs & Stratton Garden

2 Answers

Xt 500 has weak spark(flywheel magneto with ignition points).poor when cold and now won't even start.fuel fine.isolated ignition(magneto,coil and points).changed coil.points fine,resistance...

It sounds to me that you have done most all of what is needed. Just take some fine sandpaper to the magnets in the flywheel. After sanding, wipe it clean, then spray it with carb cleaner to remove any possible residue. Now give the magnets a spray coating of clear polyurethane coating. The flywheel will never rust again. Replace the source coil and install a new spark plug. A plug that is carboned up can lessen spark voltage. The last item is the battery. A weak one can rob power. Please rate my answer. Thanks.

Jun 03, 2011 | Yamaha Freedom Topper Motorcycles

1 Answer

I have a brigs & stratton classic 35 engine 9d902-2022 e1 00032451 will not start it has a very weak spark could you please advise and could you also give me the gap measurement between the magneto and...

Hi John and welcome to FixYa, I am Kelly.
The gap between the flywheel and the coil is 0.0125. The easy way to set it is to get a pack of book matches tear out the matches and use the cover between the magnet and the coil then loosen the coil mounting screws allowing the magnet to pull the coil onto the match book cover. (This has worked flawlessly for 40 + years on literally hundreds upon hundreds of engines regardless of brand.)

Weak spark is caused by either a parasitic load on the kill wire or a bad magneto

Your parts list is here:

If the control wire item 270 of the below link is fine / not grounding or chaffed. This little wire is notorious for grounding at the flywheel brake engine stop terminal and under the flywheel before the magneto.
then the most likely failure is a weak Magneto (Item 333 above)

Also make sure to check the high tension lead where it comes out of the air-shroud.

Lastly... use a phillips screwdriver in the spark plug cap making a small gap to the engine for checking spark. A bad spark plug can act like a resistor and show weak spark. HOLD THE HANDLE only on the screwdriver.

May 30, 2011 | Briggs & Stratton Garden

1 Answer

I have a cs 4000 ser 00135 series that I am unable to get a spark... I replaced the coil, magneto, plug, flywheel is good... is there a ground somewhere that I am missing?

The ignition switch or it's wire to the magneto might be worth looking at. Remove the switch connection from the magneto to see if you can get spark. The switch grounds the magneto circuit when it is set to 'off'. Good luck!

Sep 11, 2010 | Echo Garden

1 Answer

Have a 5600 Gen. with 10 HP B/S engine OHV. Did great during Rita, replaced carb- changed gas-replaced plug- doesn't want to fire it seems. Where Can I find the magneto ? Are there points on the flywheel...

The magneto is by the flywheel. Depending on the age, there maybe points under the flywheel. If so you remove the flywheel and there the points are. Sometimes bugs build cacoons between points, make them inoperable. Newer engines have electronic ignition though. Follow the small wire from the magneto coil ( where the spark plug wire goes) it will either go under the flywheel through a plastic bushing, or to an electronic module. The magneto coils do fail you can test with an ohm meter. Before that test for spark. You can remove the spark plug, and let it rest on the engine to get ground, and turn the engine over. You always need 1-spark, 2 fuel . If you have spark, see if it will hit on starting fluid, if it does, then you have a carb or fuel filter issue. Those shut off valves on the bottom of those tanks, can be a problem

Jun 29, 2010 | Briggs Stratton H7159 & StrattonĀ® 5500,...

1 Answer

Magneto wires got ripped out.

Arboristsite dot com. Please do a search to see if your question has been asked before you post. Lou

Sep 02, 2009 | Husqvarna Chain Saw 20" Bar

1 Answer

Craftsman 21'' Lawn mower won't start

In order for there to be a spark at the plug, make sure the plug is grounded to the engine, it will not "fire" if it isn't.

Remove the cover with the crankrope, there should be a thin black wire going to the coil, going to a ground lug that kills the engine. Try unplugging this wire and re-check the fire...if it fires, there is a fault in this wire and should be replaced. The mower will run without it, but will not stop without "choking" out the engine

Apr 15, 2009 | Craftsman Garden

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