Engine Trouble Engine wont start? TROUBLESHOOTING GUIDE

Had the engine since the 4th. 1st all my connections are soldered. Saw the cheap connection from CDI to plug..cut it off and replaced it with the spring type, came off of an old lawn mower. Had a problem not starting, I..took screw out of bowl and had fuel flow. Removed plug to check compression and spark..good compression, no spark. Took a test light connected to ground and each lead...dead coil. Had a coil in 3 days and the road is on fire. Another thing...this engine is painted black, last time I get a painted engine...spilled fuel on the engine, and when the engine gets to operating temperature I have a dripping mess, that paint won't come off my hand with soap and water, so I know it's not oil. Never seen a easier engine to either diagnose or work on. Will be getting another one so I'm running it like I stole it..lets see if this thing comes apart.
By the way...I haven't replaced a plug yet, haven't checked if the auto parts can crossover the number...what number NGK plug are you using and if anyone has had problems with a replacement plug. Had a Suzuki that wouldn't run on ANY plug besides a OEM.
 
thanks everybody

Hi everybody, I want to say thank you to everybody who's posted. Your help has been great. I know I wasn't the one asking for help but your guys posting for others has helped me alot. I had a spark plug that had a nice blue spark but my engin wasn't running. Then I read about how a spark plug may spark when you check it but won't under compression. That was my problem. New plug (NGK 6HS) and no more problems. So thanks everybody for all the help.
 
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Here are the specifications for the mag and CDI. You'l need a multimeter(under $5.00 @ harbor freight)
To check the mag set mutimeter @ 200 ohm (scale with pic of the upside down horse shoe on multimeter) use either lead red or black it doesen't matter for this test and touch the black wire with one lead and the white wire with the other, your reading should be around 2 ohm. Next using your lead wires from multimeter check the blue wire to the white wire, should read around 300 to 400ohm's.
To check the CDI set the multimeter @ 200k same scale as above. POS. lead (red one) to blue wire neg. lead (black one) to black wire, should be no activity on multimeter (infinite) reading. Next POS lead on black wire and Neg. on blue wire should read about 130 to 150 k ohm's. Next POS. lead on Spark Plug wire and Neg. on blue, should read about 135 and 155 k ohm's. Next POS. lead on plug wire and Neg. on black wire. should read 2.5-2.7
 
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Hi All -

If you read through all the previous postings, by now I hope your engine has fired up and have ridden it for at least a few days.

My cantankerous engine has 960 miles on it. It is painful to start when the engine is cold. It is no exaggeration when I state that I have pressed the tickler button a few times and held the choke in place for a few hundred feet. But the foolish engine still takes five minutes of peddling or a quarter-mile (whichever is longer) before it will fire up and stay lit. It might sputter a dozen times before the engine remains running. My digital tach says spark is being supplied to the plug at 2200 times per minute while cold-spinning. The engine starts easily once it is hot after running for a few minutes.

With that ramble..... I read one fella pre-heated his cylinder of a cranky engine with a hair dryer before taking it out. He claims it made starting much easier. I am going to try the electric dryer, or heat-shrink gun (stay away from open flames, propane torch, etc.).

I thought I'd pass that tidbit on to someone else who has a hard-to-start engine.


MikeJ
 
Thanks a lot for posting the troubleshooting guide for the magneto and cdi... I made myself a checklist and I'm going outside to test with a Fluke right now.... I'll be back to post my results in a few. Hopefully I can diagnose the problem.
 
OK, so here are my results.

Magneto

1) should be around 2 Ohms, my result was 2.5 Ohms Good?
2) Should be 300-400 Ohms, I got infinite, and with the fluke on "automatic range" I got between 4.5 KOhms and .8 MOhms (I think this is the culprit)

CDI

1) Infinite reading. Good.
2) 130-150 KOhms specified, My reading was 306.3
3) 135-155 KOhms specified, My reading was 308.8
4) my reading was 2.5 K Ohms, so this is good.

My understanding from the results is that my magneto is bad, because from what I can tell, the resistance through the windings is WAY too high. What about the readings on my CDI? Are they OK, even though they seem to be high? Should I get a new CDI, too?
 
Jay Bhavsar, this really needs it's own thread. This has nothing to do with the original thread.
Your rear wheel sprocket is about half the size it needs to be.
What you are calling a "choke" is actually a fuel valve on the carburetor, not a choke. Your bike has 2, one on the tank and one on the carburetor. The lever down is on, sideways is off.
 
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