jlcc

I spent all day today working on my hotbodies lightning
truck and can't seem to get the engine running good.
It starts up just fine on the starter box and iddles great.
But when you give it some gas, as soon as its done burning
that gas and returns to idle, it dies. I tried all day setting
the needles and just can't get the thing running right.
It was the first time i fired it up, (note that this is a used
truck). It has the picco .27 engine in and i didn't know what
the guy ran the engine on (20%, 30% etc.) and i already
had a 30% gallon that i had baught earlier for another
car so i just decided to use the 30% i had. I let it idle for a
whole tank, which wasn't much of a problem with an
ocasional stall, but when i go to fine tunning it to get it able
for me to give it gas, it just keeps doing the same thing over
and over again. I give it gas, the rpm goes up, but stalls
right when it returns to idle. Weather the idle is set to be
high or low, it stalls. I just can't get the thing to idle got
after it has been given gas. I changed glow plugs,
Engine has great compresion. It feels as if it is running lean,
but i only got the temp to go up to 220, and it jitters as
if the low speed is lean. And if i try to run it too rich, it
again dies. Any idea on what my problem might be,
And does anyone know what glow plugs are recomended
in the engine? Thanks

giddyuperic

I am not sure of what you are talking about is it that when it returns to idle it dies? Or is it that when you take off from a idle it falls on it's face and dies? If it is the return to idle thing then have you adj the idle stop screw?

hpi apollo

idea #1: use search feature
ided #2: read this guide i wrote http://www.rcuniverse.com/forum/m_5517128/tm.htm

jlcc

I keep adjusting it, its as if it don't want to stay stable.

HeLLsGoD

Try richen the LSN 1/8-1/4 and put the idle up nearly 2mm opening, see if it stills stalls then

jlcc

okay ill try again tommorow, this is the trickiest engine i have tuned yet, did a traxxas 2.5 jato, orion wasp .26 and big gengesis for one of my friends, i have never had this much trouble with a engine yet. It idles good, but when you start giving it gas, it eventually dies. I hear these picco engines are good but i haven't gotten any good out of this one yet, Hope i can get running soon. I also had some clutch issiues which also ate up lots of my day, but thats been fixed with some shimming hear and their, just hope my picco isn't defective somewhere if so il sell it to someone who wants to rebuild it and get my self a .28 wasp, which i find works frikkin awsome.

NITRO FUMES RULE

Just a thought. Your engine may have an air leak causing a lean idle condition.
Pull engine and seal carb base, fuel inlet or banjo fitting, and main needle on carb.
Then seal the engine backplate using sensor safe silicone sealer. Also change your
fuel lines as they can have pinholes and this will cause tuning nightmares. If doing
these things don't help check your fuel tank o-ring seal and also check for cracks by
holding tank underwater, and blowing thru fuel line to check for any bubbles. These
are cheap fixes and may or may not help but at least you have eliminated some
possibilities.

If you are not smelling nitro fumes and listening to the sweet song your not LIVING !!

jlcc

OK i definatly have a problem, took the clutch out and i found that the crank shaft will move side to side for about an inch!! What the heck is wrong, are my bearings done, and if so can i even get replacement bearings for this engine since its discontinued? What luck, this really suks, i gues i need a new engine.

HeLLsGoD

Its not worth replacing your bearings unless its a $500+ engine. Its a b!tch trying to take them out. You have to bake the crankcase in the oven and try pop them out. Its best you just get a new one.

Are you sure its your bearings thats the problem? Check the internals of the engine and see if its all in place

125cchyperman

Ok Yes it is worth replacing the bearing. Even if it's a $100 engine, a set of bearing may cost $20 and the engine will run fine (if thats all it is). A new engine would cost $100+ easily when all you needed to do it spend $20 to $30 and tear the engine apart and bake the case, and thats trully not that hard to do. But it's not that hard to do and and if the engine is already out of the truck then it may take 15 minutes to tear it apart if your not familar to taking these engine apart and once you get the engine apart it will take 30 minutes of baking the engine at 375 to get this out.

Now the engine has to be completely torn apart to do this but it's trully not as hard as HeLLsGoD makes it sound. It's more time consumming then anything really.

But if the crank is movig that much (which is kinda doubt that it's moves an inch but I dont doubt that it does move though) it's more then likely the bearing if it's moving more then it should.

HeLLsGoD

You can try if you want but youll probably end up just saying f this! Once you have problems trying to take out the front bearing while its blistering hot. The bearings are tightly press-fitted from the factory to ensure leak free. Feel free to try it urself if you want..

or you can just go to engine modding shop and get them to replace it for you, its gonna cost you but they have all the tools like bearing pullers and stuff