bought a replacement engine and it wont start.

mathersi · Apr 6, 2011

So... i got a new engine and i loaded on my old carb, sparkplug, exhaust onto it. I tried to get it running and it just wouldnt work. at one point it started for about 3 seconds but then i slowed down and it turned off.

now i cant get anything to work, if im going at a fast speed and let go of the clutch the engine wont fire up but makes a noise ( just the piston moving? ) and i slow down to a stop....

im really getting frustrated with this and would love if the community can help me out with suggestions until i fix this stupid problem -.-
:-||

mathersi · Apr 6, 2011

also, im fairly new with these bikes... i bought mine used from someone and it worked perfectly but at the end of the season i snapped the bolts doing maintenance on the exhaust so i decided to buy the new engine , now that im having the problems with.

rat bike · Apr 6, 2011

if you can shoot me some pics also some more info would be great. sounds like maybe wiring or spark

Comrade Alfonzo · Apr 6, 2011

Yes, me thinks somthin' in the ignition line, possibly magneto, they is really flaky. Or CDI

mathersi · Apr 6, 2011

alright heres some more details. i bought the bike used off some1 before winter and used it like 5 times and everything was perfect. I went to tighten my exhaust bolts for maintenance before a ride and the bolt snapped and i basically had to get a new cylinder body but instead i got a replacement engine.

i installed the engine onto the bike, took my old sparkplug carb n what not and put it all on the bike. The wiring is blue/blue and black/black but the cable splice for the killswitch is kind of sketchy but its store bought.

the bike worked for like 3 seconds and then just stopped and now i cant get the engine to make the starting sound or anything when i release my clutch it just makes a rough noise and slows down to a hault.

im not to experienced with this stuff but my guesses are it could be the sparkplugged not put in properly into the new engine? maybe my carb got all guey on the inside over the winter?

i also tried using the bike a few times with out doing something with my white cable that was sticking out could that be it?

ps. i will post pictures tmrw to give some more information to you guys
:-||

dmb · Apr 6, 2011

did it ever run? you said it ran good but you broke exhaust bolts and then bought a new motor? mine wont start with out the choke 9/10 closed and full throttle at 70 deg in so cal. if you are sure theirs no spark [no kill switch hooked up] take the plug out grap it tight and have someone turn the motor over that will answer your spark question.

mathersi · Apr 6, 2011

sorry, i dont fully understand what u mean... how do i check the spark plug ?

2door · Apr 6, 2011

To check for ignition you must remove the spark plug from the engine. Reconnect the plug lead to the CDI and hold the plug firmly against the cylinder head cooling fins. Either suspend the rear wheel or push the bike forward at a good pace, clutch engaged and watch for a spark at the plug's electrodes (the end of the plug that would be inside the engine if it were screwed into the head). The wrench flats, or the area where you put the wrench or socket needs to be in contact with the engine cooling fins to complete the electrical circuit.

Keep in mind this fact: The engine needs three things to run. Fuel, Air and Ignition. You'll need to confirm all three then get back to us with what you find.

Fuel: Disconnect the fuel line from the carburetor, open the petcock on the tank and see if fuel is flowing.

Air: Remove the air filter and look into the throat of the carb. Operate the choke lever. Is the choke open? It should be.

Check these things and get back to us with what you find.
We'll get you going, we just need some information first.
Tom

mathersi · Apr 6, 2011

thanks a lot 2door, ill wake up extra early tomorow to get started

mathersi · Apr 7, 2011

well i checked my spark plug and i think its dead, its like all brown on the inside so i decided ill order a new one for $5.

i then noticed my idle screw was missing on my carb so i will be buying a new one also.

hopefully after i put the new sparkplug on and install my new carb the bike will start.

if it doesnt start after this i will lose all hope T_T

2door · Apr 7, 2011

Don't give up. We'll get you running.

Spark plug color has nothing to do with if it is working or not. Brown is actually what you want to see but that comes later. Did it spark when you tried the test I described above?

For test purposes you can plug the idle screw hole with a piece of tape. Is your carburetor one of the earlier, NT style or the trouble prone CNS type?
Tom

mapbike · Apr 7, 2011

drill out the broken bolts in the other engine and put it on another bike, broken off exhaust studs is an easy fix...............! drill bit and an ease out/broken screw extractor, some new better quality studs and you are off and running like a herd of turtles..........! Weeeeeeeeeeeeeeeeeee!

Seriously, dont trash the other engine over those broken studs, like I said an easy fix.

Hope you get the new one going soon and running great after it's broken in...Good luck

Peace

mathersi · Apr 7, 2011

Its the NT carb. im goin to try the spark plug test again, but i believe i was doing it right and saw nothing.

ps. I emailed the person i bought my replacement engine from and hes sending over the rest of the kit for $60 -.-

dmb · Apr 7, 2011

the cdi and the spark plug cap have small screw type ends that the plug wire screws into unscrew both ends and cut 1/4'' off each end you should see copper wire in the center then screw the cut ends back together try what 2 door said to check for spark. i said grap the wire if your sure theirs no spark to check to see if you get shocked, sorry my bad, thats what i tell my freinds. i'd go to honda buy a b6hs[ngk]spark plug 1 foot of copper core wire and a new ngk cap $18 and not worrie about these iffy china parts. stick with it your be ok and use some freezer bags and coffie cans to keep your parts you take off in.. they do run away. dennis

ajax · Apr 10, 2011

try ditching the kill switch they can ground out your electrical and i don't have one nothing but headache.

DaveC · Apr 10, 2011

I read where you were messing around with the white wire. This wire is for a headlight and hooking it up anywhere else can cause the magneto to be shorted out. Until you get a headlight meant for one of these cover the end of the white wire with tape so it does not ground out your magneto.

The fuel mix screw you lost also had a spring that was to keep the screw from backing out. If you replace the screw without a spring you will lose your new part real fast. If they do not send you a spring one from a ball point pen will work with minor modification, usually just shortening it up.

That it ran for a few seconds is encouraging. At least you know it will run, eventually

mathersi · Apr 11, 2011

hey guys.... so all my parts came in today, i put on a new carb, fuel line, sparkplug, and the black box that connects to the sparkplug........ im getting the same problem i start peddling and when i release the clutch the engine just makes a noise as if its off and i slow down to a stop...........

im gona kill myself soon T_T

darkhawk22 · Apr 11, 2011

if the idle screw isn't there as you mentioned earlier then it won't run, at least for long. You need to have the idle screw in there and turn it in a few turns to push up on the internal mechanism that pulls up on the needle and allows gas to flow.

mathersi · Apr 11, 2011

not sure if u read my last post right, i just got a package with all new parts today.

i installed the new carb on and the idle screw is there, and i can also see the slide moving up and down when im twisting my throttle.

problem still goes like this: peddling and when i release the clutch the engine kinda goes glubglubglubglub and i eventually stop after a few meters.

ps. the engine doesnt even sound like its starting or anything, i put in the new sparkplug and used the new plugcap and everything.

mapbike · Apr 11, 2011

NO fuel or NO spark or WRONG timing or NO air.....!

The glubglubglubglub......... you spoke of tells me you must have compression, the only other basic things you need for an engine to run is listed above.

Take the small screw that is on the very bottom of the fuel bowl out and then turn on the valve at tank and see if you get a good flow of gas.

Take off the side cover that covers the ignition coil and check the wires very closely for any possible nicks that could cause it to ground out and kill the current to the CDI.

If all of this is correct and the wires to the CDI are hooked up right then, I say with that ignition side cover off I would take the flywheel nut loose and remove the flywheel to make sure it doesnt have a sheared Key, if it does then your timing is off and even though you may have Fuel, Spark, & Air it will never run if that key is sheared and the timing is wrong.

If everything I have listed here is right that engine will run....

Hope some or all of this may help, Good luck!

Peace

.kick2

I know you feel like this now but it will get better, just hang in there!

bought a replacement engine and it wont start.

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