Engine Trouble Engine wont start? TROUBLESHOOTING GUIDE

KCvale

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You drive chain may not be straight or too loose and the chain bunched up against the front of the back left side cover where the clutch arm goes in.
Pull that cover, you'll see the scratches in the cover, just cut out where the scratches are in the cover.
 


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what the hell happen to my post bought a CDI from BikeBerry junk out of the box brand new junk expensive bu berry said take shot for them to see thats big relief cuz I don't wanta pay for shipping a dead thing back so they can toss it in the garbage in California I did the sparkplug test at ight had thousands of sparks went to bed with a smile next day tried to run it not even a pop the thing fluuxuates did the test again no spark ohms should be around 6 to 8 ohms not 171 means to much resistance.
 

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Use ohms on a volt meter mag 300 to 450 ohms CDI
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.
Glad to hear some good news I 'd piss on a hot spark plug if would turn my engine try it tomorrow
 
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Hi ; I bought all new electrical components before I read this. The addition of new CDI and Magneto did nothing to help my bike not starting.. went through the included guide Not the problem; still will not fire. I did pull the head and finally the body only to find a broken piston ring; no compression, no fire I guess?? Anyway, will order new rings tomorrow. I managed to break one ring then another, and then the third. Awful brittle lil gems!!!

I am sure there is an easier way to load the rings and get them back into the cylinder. I tried just squeezing them but found it very difficult. A friend said he uses hose clamps. If you know an easier way, please let me know. Also, if anyone can tell me where , other than off the internet, i.e. bike shop, moped shop, etc. that might sell what I need, it would be appreciated.

Thanks for the advice!

Gary
Got be careful and look inside the ring grove there is a little kiss button that part there is for the slit if you place it over way to goddamn big you'll never get your head over it also you must have at least 2 head bolts in to slide it over got to be match just right the is a sinch to know those 2 things had auto parts teller tell me take a large rubber mallat bang it the kid was f***ing nut don't do dont force if there need be forcce take another close look to see the ring did not turn over the kiss button you may need to reposition it other than that its a breeze.
 

jaguar

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I install the piston/rings into the cylinder while the piston is disconnected from the connecting rod.
Then holding everything in place I install the wrist pin, bearing, and clips.
 
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If your Happy Time engine isnt starting then work your way through this guide to identify and fix the problem. Still no hope? then just ask...
With many thanks to BoltsMissing who compiled this great troubleshooting guide. Thanks to Lordoflightaz too for a few tips :)


Firstly start off by checking that the fuel petcock is on and you have fuel. Check the wires to the CDI. Make sure that they are connected. The cheap connectors come loose
You forgot something got spark, got gas if wont run you got crack! No toe rope will start it!

1. Remove spark plug, check gap.
2. Check for spark with lead on plug and earth spark plug on cylinder head fin.

Lift the rear wheel, and give it one good hard pedal down as if you are
kick-starting a bike. If plug sparks at the tip, re-install the spark plug. (just bear in mind that I have had plugs that fire under no compression(Not in engine)but had no spark under compression(In engine)This can be a pain if you Don't know this.You could pull your hair out with this problem,new plugs are cheap!)

2a. If no spark, check Plug cap. I had to replace mine with a NGK Right Angle spark plug cap, (don't know the part No. though)
2b. Repalce lead anyway with Copper wire lead.
Check for spark again with new lead and plug cap
That's the electrical done from start of lead to end of plug tip.

If Spark, then go to Fuel.
If No Spark, go to Magneto and CDI.
But don't just replace the Magneto and CDI unless you do all the obove to.
That way you have a clean sweep out of sight out of kind type of thing of the electrics.

Fuel.

Remove Carby, AFTER Spark is all clear as explained above.
Remove fuel bowl, see if it was full or any fuel was in there.
If not, check fuel line and needle/seat where the fuel line plugs in.
There may be some grit.
If it had fuel in fuel bowl, re-fit carby.

Fuel is OK up to fuel bowl end.

Clutch adjustment, just go through the motions at the cable end. There should be no slack.
Can't say much about whats behind the clutch cover, never had one with problems ,yet.

By this time you probably flooded it trying to start and doing the other testings.

Then as last resort as I mentioned earlier,
Tow start,
and this will "flush out" the remaining cob-webs, and it ought to go.
Tow around the block or whatever until all reasonable doubt is undoubted if it still don't start. Be very careful though as this could be dangerous!

Failing a tow start, then start the inspection process again the next day, so take a break, it's only a Happy Time (HT) engine.
This time check for Head/Lower cylinder/Exhaust and Carby Gasket leaks etc.
Point is, dwelve deeper into the problem.
Tow again if all looks OK.

Remember if an engine has compression, fuel (air and petrol) and a spark then it must fire, it doesnt have a choice! ;)
 

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Chandlerm

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I got it from the same person with same issues and yes the bolts are garbage. Did you figure out the solution because I really have the same problem.
 
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I had my engine start 3 times today, I brought the bike into my garage to tighten the chain back up and went to make a sandwich. When I came out to start it again to go get my check, the engine would turn over and start and I was getting fuel in because it revved ip and down the way it should, but as I was pedaling the bike started to slow down and eventually stop, never getting to actually ride without pedaling and somehow never got the engine to run on its own. What could this problem be? Everything is brand new, plug is fine, gets spark under conpression and without. Its just when I pop the clutch, give it gas and keep pedaling that it starts to slow itself down and turn itself off
 

jaguar

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1) plane flat your cylinder head with sandpaper on glass.
2) clean the shellac off the stator coil at the 4 spots where the heads of the mounting screws press onto it. that is the electrical return path for the spark current.
3) make sure the crank seals aren't leaking
 
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Darshit

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Hey guys. I just completed assembling my 80cc Chinese engine on bicycle. Went for the first ride the engine did fire up but was not idling and i had to pedal constantly to keep it running. Not able to figure out the reason. Can this be issue of spark plug or it something else?
 
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Hey guys. I just completed assembling my 80cc Chinese engine on bicycle. Went for the first ride the engine did fire up but was not idling and i had to pedal constantly to keep it running. Not able to figure out the reason. Can this be issue of spark plug or it something else?
Check to see if you put your fuel filter in backwards there an arrow on it you might be getting just a trickle of gaz.
 
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Hey guys. I just completed assembling my 80cc Chinese engine on bicycle. Went for the first ride the engine did fire up but was not idling and i had to pedal constantly to keep it running. Not able to figure out the reason. Can this be issue of spark plug or it something else?
Are you saying that it's firing but but the engine will not pick up rpms when giving it throttle?
 
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Hi what would it mean when I undo my mag cover an fuel come out of were the magneto sits and also will a small imperfection in a piston stop a motor running I've got like a little graze tYpe thing on the edge of my post on an its,a tiny bit deep can rub my nail on it and deal it
 
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fuel in the magneto is likely a bad seal behind the magnet rotor. I had a seal come out with the rotor when changing the rotor. Thing is the seal was not leaking. I got a seal retainer off EBay $7.00.
Was a little worried about the rotor touching it, but so far so good.
 

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