so i have a hitec 7940 servo that does throttle duties in my buggy. when the servo is powered on it works flawlessly, have not had a single problem, but when it is not powered on and i try to move the servo horn back and forth it does not move freely like it should. i know its not right cuz it didnt do that when it was new and my 7950 in steering moves back and forth freely. does this sound like the servo is going out?

Is there any of the linkages that are binding and cause it to feel like that ? I havent owned a 7940 but some servos mover easier than other when they are off.

Description too vague; please expand. What do you mean by "does not move freely?" Does it produce a notchy, uneven resistance, or something more consistent?

Better pull the horn off and check everything. Probally the carb binding, but a blown Hitec often locks up.

notchy, uneven resistance explains it perfectly. the linkage is not in a bind anywhere and there is nothing wrong with the carb. it has been like this for about a month now and i havent done anything about it because i havent had a back up servo to send this one back. i guess i can just send it in to hitec. whats the worst they can do.. send it back to me and say nothing is wrong with it???

and just to clarify, it has the "notchy" feeling even when i just have a horn on the servo COMPLETELY out of the car this is how i know its not the linkage or the carb

I have same issue with a brand new Hitec 5996TG I am using on Mugen MBX6 throttle. I can't seem to find a rubber band that is powerful enough to pull it back to neutral in the event of lost power. The previous servo I had worked flawless, just lacked speed. I double checked all linkages, etc. Did I get a bad servo? This model is no longer made by Hitec but LHS had a bunch of them on sale.

anyone know the screw size for the 7955tg.. i lost mine yesterday

dude just search hitec screws they come on a packet.

It's a 2.6mm. Amain has a cap head made by HPI that works perfect and no more phillips screws

Hope this helps

Somin wrong with your servo. I got four o em in a 30% plane and they all move easily and smoothly. Having a high speed/low gear ratio they will be easier to move than the 7950's