Engine Trouble Engine wont start? TROUBLESHOOTING GUIDE

well today I took apart alot of components. I took the carb apart and it would not stop leaking gas..Even with the petcock on off. so I drained the bike and put the gas in a tank.
does anyone think the engine might have flooded over time?
I took the air filter off to find it soaked in oil. so i cleaned it dried it out and put it back. I put the bike upside down to see if anything would come out of the spark plug hole. but nothing. If i'm not mistaken, shouldn't gas have been spewing out of that hole?
 
Were you able to determine wether you have spark or not?

If it has flooded to the point of being able to dribble out of the spark plug hole with the bike up side down, the piston would have to be near the bottom of it's stroke. That way the transfer ports inside the cylinder will be uncovered allowing a path for the excessive fuel to flow through. Still, not all of the excess fuel will be able to get out. The underneath portion of the piston will act as a cup and hold some of the fuel. The only way I know of how to get it all out is to rotate the crankshaft until the piston is at the bottom of the stroke. Then rig up a rubber hose about the diameter of a pencil to a blow gun and through the spark plug hole, fish the other end of the rubber hose down into one of the transfer ports. Blow out the crankcase this way for a few minutes.
 
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:rolleyes:
well i did have a blue spark. Turns out one of my wires came loose and was making false contact with the other wire. Its running up to par. thanks alot gearnut once again!
 
Congratulations on your repair!
The best way to insure that the electrical connections will be good and stay good is to cut off the cheezy factory connectors, strip and solder the wires together, and use heat shrink tubing to seal and insulate them.
 
spark plug

Ok so i have read this in a few different threads now. It is possible for the spark plug to fire when outside the engine but not inside under compression. How are you supposed to check if it is sparking when inside the head?

I ask because I am having trouble starting my engine, I replaced all of the electrical from the magnet coil to the plug so everything is new and i am successfully getting a spark at the plug when it is outside the head. I am also getting fuel into the carb. Either i have an air leak somewhere or my carb is acting up OR it could be this spark plug problem.

Any way to test this? The plug looks good and clean when i examine it as it is new.
 
Yes!
It could be caused by a bad spark plug or a poor electrical connection to the spark plug wire at the CDI box or spark plug boot where they thread on.
 
well this thread is a few months old. but i am having a problem starting my engine so i thought id post about it here.

i have an sd stinger engine kit, 80 (66) cc. i just bought it about a month ago and its my first build. i have taken it out for 3 rides. each time it was very hard to get started. but it would eventually start. after the second ride i noticed it was running much too rich. so i put the clip on the needle on the second from the top notch. it was on the 3rd notch from the top. so on the 3rd ride it performed alot better. and the plug didnt get fouled. i am using a 16:1 mixture, and the stock spark plug. i have run the engine now for about 9-10 miles. the 3rd ride being when i put the most miles on it at 7 miles. last night i took it out again. but of corse it wouldnt start. i tried for 2 1/2 hours but no go. now im not sure if this has anything to do with it, but last night it was -18 degrees. the coldest i can ever remember it being here in western new york state. i did everything i could to get it started but it just wouldnt work. has anyone had a problem starting their engine in such low temperatures before? actually theres probabaly very few of you who would even think about riding their bike in such weather. but i was dressed for it ; )

if it wasnt the extremely cold temperature not letting the bike start it might have been because it got flooded. when i took the air cleaner off i could see some fuel pooled at the bottom and also the bottom half of the air filter was soaked in fuel. i know i have spark, and i know the clutch isnt slipping. so what would i do for the engine being flooded? ( i did take the spark plug out and engage the clutch and pedal for a block or so. is there anything besides that you can do?) also if i just leave it set long enough wont the fuel evaporate out?

also 1 more question. say if your oil to gas mixture is more than 16:1. say its something like 14:1 or 12:1 or 10:1 would this also cause the engine to not start? or if not what would it cause? because its possible i added too much oil to the mixture. not by ALOT alot, but maybe an ounce or 2... i also used 91 octane gas. as it said to use in the instruction book. but i cant see how with such a low compression engine higher octane gas should be used....?
 
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If you have been having trouble starting your engine at normal ambient temperature then the extreme cold would definitely compound that problem and could cause the engine not to start. I would think about going to a lower oil:fuel ratio, i use about 25:1. As far as flooding the engine goes it sounds like you did just about all you can do, unplug the spark plug and ride it for a bit, that should spit out all the excess fuel. If all else fails try getting some starting fluid and shoot a bit into the air intake (after taking off the filter).

That being said i live in boston where it was around -15 or so a few days ago and i had a tough time getting my bike running. Havent had any problems lately but the cold will definitely make it hard to get going.
 
i have a piston question if anyone can answer it.
I have the head off the engine.
are u suppose to be able to see the manifold hole when your piston is all the way down? mine wont show but i can see the exhaust. (i had to swap out the top half and maybe this is my problem to my engine not wanting to start.)

ps it ran for about a minute at 5 miles and hour. never started again.:eek:
 
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
 
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