Problems Experienced today starting JATO to RE-TUNE

[jamie_horwood]

CAR STILL STALLING ON FASTER ACCELERATION. I performed after run procedure with after run oil. Fitted freshly charged battery to EZ start and fitted new Super Heavy Duty GLow Plug. The Low Speed needle is at 1.75 turns open. High Speed needle is 4 turns open.

I don't know where the idle speed is or should be but its idling at high rpm. I know the HSN and LSN are supposed to be right. Are these factory settings overly rich or not for HSN and LSN? It took a while for the engine to start. I think I just kept covering exhaust to prime and also just tried 2 second bursts on the starter. It did take at least 5 minutes but then it was very cold out this morning. I think It finally started later because it got warmer with the sun beating down on ther car.

After a few minutes idling high it got quite scary as the car tried to pull away from me so I did lower the idle needle a bit to stop it from pulling away.

I started to see lots smoke from the cylinder Head after a minute or so idling at high rpms. I don't know if this is because there is burnt or burning fuel inside cylinder head or whether it's a combination of this and the plastic tie wraps holding the cylinder head protector in place as it comes loose.

When I noticed the engine getting hot and smoking I tried a few high speed passes then leaning by 1/4 turn.

Can someone help me out so I can try fix this problem. I keep getting confused which settings I have changed then I have to start all over again from square one. Leaning and richening a bit didn't seem to fix the stall on acceleration. I want this to be gone. Why should the car be stalling on acceleration when its at base settings. This is so annoying. I can't have any fun as I accelerate faster it just stalls.

Edited February 17, 2008 by jamie_horwood

[MANNY]

Check the pressure line that goes from the exhaust to tank is ok.Then check the seal on the fuel tank lid is seated ok.

[jamie_horwood]

Hi MANNY. How do I know if the pressure like is ok? When I emptied the fuel tank to perform clean on engine. I noticed bubbles in the fuel line. The fuel cap lid closed firmly as I tightened the lid with the wrench.

Edited February 17, 2008 by jamie_horwood

[MANNY]

Just check its connected ok and nothing is blocking it.Open the lid on fuel tank and make sure the rubber seal is seated in the groove .

[jamie_horwood]

Yes I can feel the rubber seal is seated ok. as I said earlier the fuel cap seems to close firmly as you can feel the pressure of the spring and everything

Edited February 17, 2008 by jamie_horwood

[MANNY]

Also the lsn should flush .Turn the screw so iys flush with the end if you know what i mean.1.75 turns is too lean.

[jamie_horwood]

All I know is I turned low speed needle screw head clockwise until it was closed. I then turned it anti clockwise one complete turn, then three quarters again. So it now looked like it does in the manual or as I thought 1.75 turns open?. The needle screw head (red) is more or less flush with the (yellow) ring pointed out in the manual around the (red) screw head. IS this what you mean ?

Edited February 17, 2008 by jamie_horwood

[MANNY]

Yeah that right.From what your describing its running too lean.Trust me they are a pig to start when its cold so nothing wrong there.Just re check your settings again and check exhaust it tight where it goes on to engine.it will be some thing easy im sure.

[jamie_horwood]

Ok. So let me get this right. I need to screw the lsn needle anti clockwise even further out right to the end. Further than the yellow ring in the traxxas manual. Exactly how many turns is this please. Thanks. please let us know. Back to work tomorrow. So dunno if I'll be able to re-check anytime soon.

Edited February 17, 2008 by jamie_horwood

[5645_1442625668]

the base settings for a jato are as follows: (HSN)high speed needle = 4 turns out from closed,this is the upper most screw on your carb next to the air filter.

(LSN)low speed needle = this is to be set flush(level) with the grey ring around the low speed adjustment screw,this screw is located in the middle of the thottle body and is right next to the EZ start motor terminals

(Idle Speed) = if you remove the air filter then look down where the air filter was covering there should be a small gap,this sets the idle speed.The screw(silver) is located just under the fuel entry nossle,the proper gap is to be around 0.5-1.0mm at idle.

MAKE SURE YOU COMPLETE A HIGH SPEED PASS WITH EVERY TURN OF THE NEEDLES!!! this is to allow the engine to clear itself and make the setting.

[helsinki98]

It could possibly be fuel starvation, you could try cleaning the carb and checking for any cracks etc.