R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric Off-Road

Thread Tools Search this Thread
Old 11-28-2005, 03:52 PM   #1
Tech Rookie
Join Date: Apr 2005
Posts: 16
Default help

having a hard time tuning my xxxxnt. two problems. cant seem to set the throttle return spring back to norm. took off air filter and looked at carb opening.though i had it set but its idling high and when i apply the break the car shuts off. also i am having a hard time starting. using spin start the only way i can get the fuel moving up through the fuel tube is by putting my finger over the exhaust. thanks for any help
peahbeez is offline   Reply With Quote
Old 11-28-2005, 05:48 PM   #2
Tech Apprentice
richb3's Avatar
Join Date: Oct 2005
Location: Santa Barbara, California
Posts: 73
Send a message via AIM to richb3

I'll give it a stab:

Your throttle return sring simply helps pull the carb closed. It is up to your idle screw on the carb to keep the idle set correctly. Increase this screw to hold the carb open further when it is forced all the way shut, which will help keep the car from dieing (sic?). This will give you a good idle, now you have to make sure your servo and return spring is fully closing the carb to that idle position.

As for setting your nuetral position, here's what I do. Try to get the servo set to provide ample throw for throttle and brakes, so set the servo horn near perpendicular to the carbs travel when at neutral.

Next, set the carb linkage so that this position will cause the carb to be all the way closed, with a little extra force to help ensure it closes each time you return to neutral.

Lastly, set the brake linkage so that in this same position, you brake is off but close to engaging. (If you want drag brake, set it here to be slightly engaged).

Now everything should be set. Use your transmitter to set the endpoints of travel for throttle/brake.

About your starting. It is ok to put your finger over the exhaust, this builds pressure that forces fuel up the line and into the carb. Once running, there is enough pressur/suction to keep fuel coming without your finger.

However, if this is a new problem, maybe you have an air leak? Check the fuel lines for cracks and make sure it is all tight and secure (is it old, have you ever replaced it?). Also check and possibly seal your carb (search around for how to do this, not too bad).

Hope this helps!
richb3 is offline   Reply With Quote
Old 11-29-2005, 10:25 AM   #3
Tech Addict
Join Date: Aug 2003
Location: north carolina
Posts: 536
Send a message via AIM to 2mcgrath Send a message via Yahoo to 2mcgrath

that is how i prime all my engines with finger over the exuast..you can get a primer bulb if you dont like doing it that way
2mcgrath is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off

All times are GMT -7. It is currently 10:14 PM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net