I bought a used .12 CV and installed it into my RC10GT2, I dont know how to tune these small blocks, and it won't start since the first time I ran it, last started about 2 weeks ago, my ignitor, receiver, transmitter batteries are fine, I primed it until I saw fuel into the carb.

I run 20% Sidewinder, O.S lc3 glow plug

Is the motor healthy? bump or pull start? CV or CVR? Which carb?

I learned on the CV line and they are super simple to tune and hold a tune. I would check simple things if you have compression. Check for back plate seal. Make sure its tight. fuel around carb. Check fuel fuel lines. Check the exhaust gas line where it goes into the muffler.

where did you buy the motor? Im on the hunt for a motor for gas truck

http://manuals.hobbico.com/osm/12cv-cv-x-manual.pdf

Yes the motor was healthy it is a CV. , I use pullstart, I used it 5 times, Never used it after 2 weeks, now it wouldn't start, I checked the plug, everything is good, fuel line is good, good compression, charged glow ignitor everything is good to go, I may have messed up the needle settings, I recently started it but for a few seconds, it sounded lean so I richened the high speed needle, but now its back to not starting

the differences now I noticed is, the pullstart is easier to pull, and it wont start

The older CV is ABN where the new CVR is abc. They also make a .15 CV-X now that is ABL. You may have run it hot and burned the motor up. Take it apart and see how far the piston will go up through the sleeve. It should gt tight before top dead center so know where TDC is.

If it is tight then reset the carb. Check for paper gasket at back plate. Check for O ring below the carb. Check that it has a good seal at the front bearing and go from there. Also check that the carbs O rings and what not are good.

Iwill also note my CV with the ABN sleeve is looser then a CVR.

Take the plug out, open the carb wide open, choke with finger till fuel sprays out, then turn upside down and pull 6-8 time to get extra fuel out, then install a new plug , then try to start if.. works for me everytime!!

Thank you, but that didn't work, what I did was cleaned out the engine. The engine itself was frozen for some reason?

i miss this old school engine. Its probably something internal your engine that should be check. take it apart, and spray it with penray or fuel,