HPI .21 3.5 engine help

[liquid10rider]

Hey guys I'm new to the site but I have had experience with the nitro scene for a while now. I just bought a buggy off of a co worker. The frame is a Kyosho, but I believe its a crow pleazer. It has an HPI .21 3.5 engine. The buggy sat for a few years. I cleaned it all up, and got it running. She ran ok but seemed very sluggish. Just today I took the engine and carb apart and cleaned it all out along with the exhaust and intake. I set the carb according to factory but she wont start. I have to play around with the HIGH and LOW just to start it. If I try to run the buggy its like theres no power. very very sluggish. if you let it idle for a minute and than hit the throttle its like a small burst than dies again but the burst is still not normal. I'm at a loss on this one. I'm praying its something simple.

Any help is welcome,
Thank you,
-AJ

 

[cbaker65]

Setting the carb to factory set ,your only flooding the hell out of it ,that's why it dies when you throttle ,
especially if you let it sit an idle!
The first thing when you get second hand stuff is to clean the fuel tank ,make sure there is no restrictions
or clogging in the fuel tank.
Do that first an make sure the fuel lines are good!
After that ,you can start by leaning the HSN in a little ,the engine should start to run better as you lean it
out.
Start in small turns in 1/8 increments ,an monitor the head temp with a little drop of water ,if it sizzles off
as soon as it hits the head ,then your too lean.

 

[Certified Mike]

Definitely agree with @cbaker65 ! I'll just add that the factory setting are no more than a guideline to getting you either broken in, or running at a baseline. That depends on the manufaturer as far as which setting that provide. At any rate, you are likely running super rich and you do need to lean as suggested above.
Do make sure that your fuel is new. Don't use anything that may have been sitting around with the kit in storage! That will just drive you crazy!
I strongly urge you to check out the guide at this links:
https://www.rcnitrotalk.com/forum/threads/nitro-rc-beginners-guide.68224/

https://www.rcnitrotalk.com/forum/threads/nitro-tuning-tips-and-tuning-flow-chart.60832/

https://www.rcnitrotalk.com/forum/threads/rc-nitro-engine-performance-tuning.102688/

It will Def guide you thru a LOT of your questions.
We are all here to help so please, fire away with any you have!!!

Welcome to RCNT!!!



Btw, post a couple pics of your kit and I'm sure we could help identify it for sure. That will obviously be helpful!

Lol... Another btw... Make sure you don't have an inline filter in your fuel line. I suggest just replacing the whole thing. Running a NEW filter might be a good idea... And be sure your carb pinch bolt is snug.
If your engine is leaking fuel, you may find that you'll need to seal the engine. There is lots of advise available here on that too. Take it one step at a time tho, go thru the tuning first.
Good luck!!!