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Norm's 2 stroke repair center Having problems with your 2 stroke engine? Just ask Norm, he loves to tinker and troubleshoot engines

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  #1  
Old 12-23-2009, 08:29 PM
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Lay'emLow Lay'emLow is offline
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Default No start wonder!

So Ive racked my brain and cannot for the life of me figure out whats keeping my engine from firing.

Ive got spark, although the plug was a little oily, but I cleaned it and still no start. Ive got fuel; Ive even cranked to the degree that Ive had liquid dripping from my exhaust (ive shut off the gas and cranked to clear the cylinder since). Ive got compression. Ive teflon tapped and gasketed the intake manifold. My fuel isnt to oily as Ive tried to run it sans oil before.

Could I possibly be running to rich? Is it possible for the timing to be off? I dont see a way to adjust timing other than rotating the mag, but that doesnt seem possible.

What else can I check/ try?? Im at a loss

Thanks
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Old 12-23-2009, 09:33 PM
Nougat Nougat is offline
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Default Re: No start wonder!

Right after I built my first HT, I loaded it up with 16:1 fuel, and it grudgingly started. Winter was approaching, and I needed to get my snowblower started, so I drained the old gas out of the snowblower and put this new 16:1 in it. The snowblower wouldn't start, even though I'd cleaned the plug. Next day, I diluted the mix to about 28:1, and the snowblower started right up.

If you run your mix too oily, your air/fuel isn't as combustible, and you end up with a lean condition. You may have read elsewhere - 16:1 is too oily. 32:1 should be fine.

No, you can't change the ignition timing on the HT, at least not without modifying the magneto.

Did you check spark with the spark plug out, against the side of the head, and turn the engine, to see the spark? If so, I'd think about fuel mixture as the problem, either change your oil ratio or adjust the needle (clip up to run a little leaner, clip down to run a little richer).
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  #3  
Old 12-23-2009, 09:47 PM
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bairdco bairdco is offline
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Default Re: No start wonder!

check your kill switch wiring. if everything else seems to be working, it could be shorted out. just disconnect it and see if it fires up.
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Old 12-23-2009, 09:50 PM
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Norman Norman is offline
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Default Re: No start wonder!

I guess this is a new engine and has never been started?
try this
NEW spark plug gap it at 0.025" .. here is the reason for this.... the spark plug you have now could be fowled out enough it won't fire under compression or has a crack that will allow it to short out. did you ever drop the spark plug?
empty your tank of fuel. mix up in a separate can 24 oz. regular gas with 1 oz. of 2 stroke oil pour this into the fuel tank. this is a good starting point for running you engine.
ok now if you have a good spark and fuel it should start.
You probably need to disconnect the cdi box remove the spark plug and pedal the bike with the clutch released so the engine can blow out what ever is in the crank case do this with the throttle wide open and the fuel turned off or with the tank drained of fuel leave the choke off. We are just trying to clear out any fuel inside the engine.
once this is done reconnect the cdi blue to blue black to black. make sure the white wire is insulated so it doesn't short out the ignition.
lay you new spark plug on the head and now roll the bike with clutch engaged so the engine will turn over see that you have a good spark if so now you can try to start the bike.
install the spark plug.
turn on the fuel open the throttle leave the choke off pedal it let the clutch out and hold the throttle open it should at least pop or start right up. if you get nothing then the next thing check the spark plug see if its wet or dry if dry pull up on the choke and try to stat it again. if it won't pop or fire up then I think the timing key is sheared or missing.
the mag will fire with the key missing or sheared but not at the right time.
to check for the key being missing or sheared take off the cover for the mag coil mark the rotor so you can put it back on with the correct side out. you can remove the mag coil if you want to make it easier to remove the magnet rotor.
You will also need to remove the cover on the clutch and put a shop rag in between the gears so you can remove the nut on the magnet rotor. once the nut is off gently work the rotor off see if the half moon looking wood ruff key is sheared or missing. the slot in the magnet rotor needs to align with the slot for the key you should be ale to tell right away if its wrong.
If you find a sheared key this is why it's not firing up.
You said you had spark and fuel so it leaves timing a the suspect problem I asked you to do the other things to eliminate some other possible causes. I hope it will start up before you have to get this far into trouble shooting it.
Other causes could be a stuck float causing the engine to flood or a crank seal either not installed or leaking very badly. Let me know if this helps
I hope all you've done is fowled the spark plug and flooded the snot out of the engine.
I'm also hoping you haven't installed the throttle side and needle in it wrong.
Not sure where you would put Teflon tape on the intake? All I ever use is silicone on the intake between the carb and the slip joint to the intake very slight coat of rtv on both sides of the intake gasket.

Last edited by Norman; 12-23-2009 at 10:04 PM.
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  #5  
Old 12-24-2009, 10:40 PM
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Lay'emLow Lay'emLow is offline
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Default Re: No start wonder!

Thanks for the advice guys. A bunch of things i hadnt thought of...

Norm, you should number that post and sticky it as a no start trouble shooter!

Im going through the possibilities one at a time... hopefully you wont hear from me again. haha!
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Old 12-24-2009, 11:28 PM
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Norman Norman is offline
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Default Re: No start wonder!

do let me know if you get it running and I hope its something simple and not a sheared key.
which isn't hard to fix just getting a new key can be a pain, the waiting time for it to come.

The little Booger( half moon Key) jumping out of the slot if you don't dab on some super glue, even then they can jump out and hide, damn things anyway.
Ok at your request its a sticky.
Norman

Last edited by Norman; 01-06-2013 at 12:02 PM.
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  #7  
Old 02-18-2010, 02:38 PM
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Lay'emLow Lay'emLow is offline
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Default Re: No start wonder!

So turns out the problem was a faulty CDI. Never would have guessed it because I was getting spark outside the motor. I guess it was just weak and possibly blowing out under compression.

Just wanted to share and thank everyone again for support!
L'eL
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Old 02-18-2010, 05:06 PM
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Default Re: No start wonder!

Good to hear you got it going.
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  #9  
Old 03-13-2010, 07:26 PM
svc svc is offline
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Default Re: No start wonder!

I just went thru this thread after having trouble starting my bike. I was sure i had a blocked carb, I have always run no air filter(no room so it seemed logical. I rebuilt my cns, no luck. Put on brand new stock carb, no luck. New plug, no luck. new cdi, no luck. Eventually tired and frustrated i opened the hatch on the engine to the wiring it was full of water. So a quick spray of wd-40 and i was off. Wooohooo


4 screws probably the easiest thing to do of the lot, i should have looked here first. Damn brain led me astray lol
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  #10  
Old 03-01-2011, 03:35 AM
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KyuNeko KyuNeko is offline
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Default Re: No start wonder!

Figured I'd reply to this thread to help people out :3

I bought me a Raw motors 66 cc slant kit about 2 weeks ago. It was the first time I had bought from Raw Motors (I had bought from zoom bicycles in the past but they no longer ship to the US)

When i put the bike together finally, i put the gas in and tested it out. it started right up! i was so happy! but after about 2 minutes of testing it out, it died, and I could no longer start it

Disappointed, I tried rebuilding and cleaning the card, and adjusted the fuel. Still didnt work.

Re-did all my eletrical. Still nothing

Tested my spark plug... worked fine! but STILL wouldnt start!!

Opened up the compartment to my magneto to see if it was wet. Nothing.

I must have taken that carb apart 10 times trying to figure out the problem.

Finally, I thought, "Okay, Maybe my CDI is bad... or even my timing might be off"

So i called my buddy up who helped me put the kit together. He suggested I try replacing the spark plug even if it "works" with a better one. Cause apparently sometimes the stock ones just dont give a good enough spark. So i figured, "Why not... its just $4 at shucks"

So i went and bought one today... stuck it in, and what do you know, it fired right up withought a problem. cept now i gotta adjust my carb again. Im running kind of lean now, but easy fix!!

Hope this helps anyone having troubles! You never know when the solution seems least likely and only costs $4

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