I was lightly bashing my HPI Hellfire yesterday, it ran fine and all of a sudden it just turned off, after that happend i tried starting it again, it would start but it would shut off instantly. Today i go and change the plug and try to start it, the same thing happends, when i was riding it earlier there was a cloud of blue smoke so it should be tunned good. Any ideas to help me get my Hellfire running again. I tried putting gas in the carb and then starting it, it would start but then die after the gas went threw the engine, yes i am priming the engine.

I just got the hellfire least week and didnt really have time to ride it, but when i did it was awsome, beside the fact that the pull start broke..

someone plz help meeee

please someone has to know the problem

Since you already replaced your glow plug, maybe the idle is not quite high enough. Try using the trim to turn up the idle just a touch.

It just turned off ? Need more info buddy.
That sounds like a WOT run that just stopped, and that, sounds like running lean in the HSN.
And if that be true, l would take a guess at a piston death if it wont run for more than a minute since.

Anyways if it starts and dies, try a different glow plug, do you run a hot plug ? Try a cold one !
And l dont mean beer ! LOL !

They can just turn off if they get WAY WAY WAY to hot, because with the expansion of the entire engine, fuel jets the lot, the tune is effected, gets leaner and leaner , until it cooks, and alloy can cool really fast, sometimes people dont notice that they have overheated.

Turn ya engine over by hand first see if it has any decent compression.

I had a similar problem (at least from what i can tell from your description, kinda sketchy). Im definetly no guru, but you should definetly reset your needles to factory settings before droppin some coin on anything. I know, it might not make sense, but it solves 80% (or so it seems) of the problems the peeps bring up on here.

In my experience (needles are a kryptonite for me) even mildly incorrect needle settings can make your engine do some wacky things which are mind boggling and have in the past really stumped me as to a solution.

Edit:
Otherwise try swapping glow plugs.
Seriously though, the info so far is like asking "theoretically, if -such and such- happens, what is my problem?"
So answer, what engine are you working with? What is your fuel nitro percentage? etc. etc.

Edit 2:
Try starting it without the air filter (just for a few seconds, its really not good, but it can provide some answers)

Generally, they shut off unexpectedly when they are either "worn-out" (which shouldnt' be your case....I assume it's new) or it's set too lean (hsn) and basically runs out of fuel. But as above, we need a bit more description of what was going on to help.

I tried it with a changed glow plug and it still wont run. im using 20% nitro, i tried it with out the airfilter and it also wouldnt start, i bought the truck used, what are the factory settings i should set the needles at.

if we know what engine it is, we can tell, if the engine is USED then it maybe older, if its prety easy to move the piston up and down via the flywheel, you have a worn out piston/sleeve, pop the engine out of the car, put the carb to WOT (remove the throttle return spring) blow REAL hard into the fuel line and listen for hissing, also go over the engine with soapy water, bubbles = air leak which can cause the engine to not get the fuel, and then die out. Do the same with the fuel tank, try replacing the fuel line if it looks older, do you notice fuel on the flywheel of the engine? one real stupid thing, check your glow driver, if its dead, then your engine will NEVER start [>:]

Its a original HPI Hellfire engine, im just gonna go get some help from a hobbyshop, i want then to explain to me about how to correctly tube a nitro engine and all that good stuff.

Get a new cheap and bad ass OS for it. Very reliable engines.

You never said it was a second hand engine in the first post.
Second hand engine, its likely piston and sleve. Half the reason people sell em is because there to lazy to re-build.lve picked up about 6 truck over the years just from, lazy people or, people who have given up on nitro, and that is usually because they find tuning an issue !

Well, if you were riding it, then more than likely it over-heated and blew the motor. I know they're fast and fun, but they're not horsies. Heehee
If you are a newbie, then just take it to your local hobby shop and let the guys there explain everything to you and show you how to tune and adjust the truck. I would also pick up a couple of RC magazines. You can learn alot just by reading and looking at detailed pics. They also have books about tuning and repairing nitro engines, or at least they used to, you may want to look for one of them as well. These will help you to identify all the parts properly and you can take them with you to the track/field to use as a reference.

L