jato wont idle

[derriksheets]

I got used jato with a 3.3 it can't get it idle the only way it will idle is to adjust the throttle rod.so.it opens the carb a little bit but then it does when i hit the brakes the clutch spring looks good and tight i have tried adjuat lsn and hsn and idle.screw nothing seems to work and put 2 newer carbs on it tried going back to factory setting then adjust but it dont really help any thoughts

 

[mrbones]

Take your glow plug out and rotate the engine and see if you can feel a little resistance when the piston reaches the top position. If you don't feel it, your piston sleeve is probably worn and has lost compression and you will need to have the sleeve pinched or buy a new piston and sleeve. (ebay for about $50.)

 

[SchrodeMode]

It sounds like your idle gap isn't set right. You need to adjust your idle screw WHILE you apply the brakes, after that you need to adjust the trim to so that slide rests on the screw at idle. If you have to trim it a lot, it may be better to take the linkage off of the servo, recenter the servo, put the linkage back on and then adjust the trim.

 

[TRXaddict]

Typically what i use to set my idle gap is an old credit card, cut a thin strip of an old credit card that you have laying around. Use it as a feeler gauge, another words.. use it to see how open your carb slide is open. then slide it inside the gap and see if you can fit it inbetween the gap or not. if you can't.. your gap is too closed and that will force your engine to stall because its getting not enough air and too much fuel.

Try that and then tell us if your gap looks correct or not.

 

[miller]

I agree with the posts above about setting the idle gap with the brakes applied. I also found on my Revo after adjusting the throttle linkage that the adjustment collar (not sure what is called) was actually holding the slide open so that idle screw adjustments didn't make a difference. Just make sure that the gap with the brakes applied and throttle neutral are the same.

 

[TRXaddict]

yep i would take the little arm ontop the servo like you see in that picture. turn the radio and then the jato on. Then turn your throttle servo trim knob to the 0 on the radio. Then set the arm back onto the servo and screw it down. and then try to set it so its closed on the carb as far as it can go to the correct gab.

I have personal experience with jatos and sometimes the brakes are very hard to set when messing with this truck. Sometimes if you have the brake rod set too far the truck will be grabing the brakes while your driving and even if you try to adjust the throttle trim so its less of the brakes it just keeps grabbing. i would forsure just pay attention to every adjustment.

but before you do that just see what happens when you set the carb slide gap. When you get the right gap then you can focus on the LSN and HSN needles.

 

[derriksheets]

Ok so when i got off.work i tried adjusting the idle.screw with the brake on the controller.on but that didnt seem to help as for the servo.brake thing it worked fine took motor off to put on my revo cause it was running a-1 but as soon at its on revo it wont idle so i put it back on jato still nothing but i lost the oring for.the header could this be the problem i am really lost or i really dont kniw what i am doing

 

[derriksheets]

Ok i cut a speedway card and.tried.it.is.it.surposed to go between the needles.or.the slide i got it on the slide

 

[TRXaddict]

The slide in the carb, there is supposed to be a gap.

This is the only picture i could find quickly.. Where that arrow points there needs to be atleast 1.0 mm gap. and the credit card is exactly that.

Just use that piece you cut and slowly open or close the slide with the idle screw until the card seems snug between the slide and carb body.