Is the new engine I just bought dead?

My method for removing debris from the crank case. If you are unable to get the pieces of broken ring out of the bottom end you may want to try this before splitting the case.
1. Remove the magneto cover. Remove the 4 screws holding the magneto. Remove the nut holding the rotor magnet, and the magnet itself. Mark the magnet rotor before removing so you get it on the right way when re-assembling. Be careful not to lose the woodruff key. There should be tutorials on youtube to cover this.
The reason for removing all this stuff is to protect the magneto from getting wet, and the magnet magnetizes the crank wheel making it hard to get all the pieces out of the bottom end.
2. Pour gasoline into the bottom end and slosh it around. Spin the crank around using the rod. Dump and repeat. If you have a old towel do all you dump outs on it so you can see what comes out. If you have all the pieces to the ring you have saved yourself a lot of work. If you don't have them all you can try blasting them out holding the engine upside down with a garden hose and pressure nozzle.
Again try to do it in a way you can retrieve what comes out. When you are all done use the fuel/oil mix for a final flush to get things lubed back up again. Good luck, and don't forget to order a case gasket if you have to split the case because the one in use will most likely be destroyed.
I would also suggest replacing the broken ring with a new one. It's a shame to do all this work and have the old ring you were talking about using from the old motor break after a short time. Or not seal properly.

Hmmm... this method isn't working for me- it's also a waste of petrol if it's not working. I broke some piston ring into 4 tiny pieces put them into old engine and 1 came out- I shook as hard as I could and I heard nothing as if nothing was inside but I'm certain 3 pieces are still inside. I'm much more comfortable just waiting for everything to arrive and taking the whole thing apart.
It's been a nice week though I've learned so so much thanks to this site + youtube and if I started again- I know I could make a working bike. I'll be back!
 
Could somebody direct me please to where I can buy a mass pack of snap rings/piston pin circlips? I took them off and I then tried putting them on again and they flew accross the room and now I can't find them.
Also is there a tutorial of how to actually put them back on- taking them off is easy...
 
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Could somebody direct me please to where I can buy a mass pack of snap rings/piston pin circlips? I took them off and I then tried putting them on again and they flew accross the room and now I can't find them.
Also is there a tutorial of how to actually put them back on- taking them off is easy...
Firstly the magneto makes the crankshaft magnetic and so are probably stuck to it , or else they are wedged between the crankcase and crank wheel . The reason they broke in the first place is they need to be compressed and be lined up with the ring end notches , taking stuff apart is a lot easier than putting back together! A good idea is to set up a camera recording what you're doing so you can watch it back when putting back together .
The piston clips you just squeeze then put in and release slowly
 
I watched youtube videos on how to put both on- I'll put the information about the end notches in practice too thanks :)
I took the magnet off and they still wouldn't come out so it is almost certainly the wedging
 
I watched youtube videos on how to put both on- I'll put the information about the end notches in practice too thanks :)
I took the magnet off and they still wouldn't come out so it is almost certainly the wedging
Just take your time examine everything thoroughly to avoid breaking things , if something seems off post here for advice, but Googling will usually help
 
Nahom. You built your first engine yourself (the one that only started once , and not properly ) ? if so you may have the magneto magnet on backwards. At top dead center the keyway on the magnet should be at one o'clock. if it's at 11 o'clock it's backwards. I bought a used bike to begin my build the guy told me the engine never ran. I went insane getting it to run. Finally looked up timing on you tube , and found out my magnet was backwards . My engine was locked up because the guy had it in a damp basement for years , so I rebuilt it ironically I put the magnet back on how it was installed to begin with . Lesson learned. Scuff your piston ,and cylinder with 220 grit sandpaper ,then polish them with scotchbright. Blow all the metal shavings ,and dust off of everything , then wash everything with gas as a solvent . Put it all back together. Mix your gas 16:1 (4 oz synthetic 2 stroke oil to one gallon of gas ) Do what I said to Both engines. Keep us posted , and good luck .
 
Nothing wrong with trying, I knew very little about combustion engines til I built an mb. Great introduction with minimal expense. Recommend lubing piston a little at first of install, the rings should never rub the cylinder wall without it. Parts do look in reasonable shape though. Keep trying the usual, spark, gas, and timing.
I have been discouraged too, but when you get it right it will be so worth it.
Cheers
 
I usually spray my entire piston and coat my cylinder with wd 40 before sliding my piston into the cylinder . Definitely don't want a dry run , that's the worst thing for any engine . welcome to the group naturegirl.
 
My magneto is fine- I've checked- also if the bike started even once then you know the electrics are fine.
 
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