Why do my servos keep frying?
11-03-2009, 09:04 AM
#16
that is so weird. i've had my 8b for a long while and i've never lost a servo. i've had airtronics and hitec for my throttle servos and none of them have failed. my 8t that i had also didn't have any issues. i'm super anal when setting it up though. i have a friend who has a 1.0 bug and he loses a servo every race day, it's crazy. i tried to set it up for him but i had a difficult time since he was using an aftermarket horn and it wouldn't allow me get the angle right. i told him to get rid of it, but of course he won't listen. oh well.
are you guys using the stock horn and the correct insert with the right teeth count for the servo? also, are you guys using the spacers as instructed in the manual? rubber grommets and screws with washers and not screwing it down too tight? EPAs set so that it's not overstressing the servo? neutral point not being overstressed by the throttle spring?
are you guys using the stock horn and the correct insert with the right teeth count for the servo? also, are you guys using the spacers as instructed in the manual? rubber grommets and screws with washers and not screwing it down too tight? EPAs set so that it's not overstressing the servo? neutral point not being overstressed by the throttle spring?
11-03-2009, 09:11 AM
#17
unheard of i suggest to find a very knowledgeable rc guy in your area and he should be able to trouble shoot and help you out . if you dont have any local then post pics if your setup and guysd here will try to help as best as possible
11-03-2009, 09:18 AM
#18
j/kiddin bro
lost 5998 servos but never either a 5955 or 7955 to date
i had/have some 5998tg servos in my buggy for over two seasons , also have some old 5945mg servos in a practice truck that still work flawless and are still tight .
11-03-2009, 04:57 PM
#21
Solid advice....exactly what i was thinking.
11-03-2009, 05:03 PM
#22
When you adjust your throttle, you want to adjust the end point while you are pulling full throttle, set your epa around 50% throttle, and with your airfilter off, see how far that opens your carb. If it opens all the way, then check to see if the carb is pulling on the motor and putting tension on it. If it is, then you lower your epa. If the slide carb is not fully opened, then increase the percentage until it opens all the way. After you have it open all the way, make sure the motor is not being pulled by the carb and servo at full throttle. You want the slide to open, but not to pull the entire motor. The easiest way to see it is if you put the truck on your starter box or something pretty solid. Pull the throttle and see if the cooling head moves. If it does, then you have too much throttle. If it stays put, then you are set. If you are just starting out and the track is pretty tame, lower you throttle epa so that the vehicle is more controllable. The only time you would want to have full power is if you have jumps where you need full power to clear. If this is the case, then you will need to learn throttle control while you learn to drive.
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This is to compensate for chassis flex. If your pulling full throttle and there is no play, it will stress your servo when your chassis flexes, if the flex happens to be a twisting motion between the motor and the throttle servo. This can blow a servo over time.
11-03-2009, 07:24 PM
#23
Tech Master
iTrader: (3)
Only time I've lost a throttle servo on a Losi was a JR 8800S that I didn't have set up properly. I killed a Airtronics 94358 on the steering, but I'm not particularly surprised. That servo never really seemed up to the task. It actually caught fire.
11-03-2009, 07:51 PM
#24
I just fried a JR 9100 servo on my throttle. This is the second servo in the past couple months granted the first one was poor quality. Anyway, I saw smoke coming from the servo seconds before it died. It got stuck at 3/4 throttle so i had the pleasure of chasing my car around the track before smashing it into a wall 
to finally get a hold of it. Now on my controller the throttle servo setting it set to "reverse" could this be a possible cause for burning this servo out? (the reverse setting on my controller allows for the servo to function is its normal manner) Also, i did not have to use the reverse setting until i bound my controller to another car. (this car has steering, throttle and aux all in the normal positions). Thanks for reading.
to finally get a hold of it. Now on my controller the throttle servo setting it set to "reverse" could this be a possible cause for burning this servo out? (the reverse setting on my controller allows for the servo to function is its normal manner) Also, i did not have to use the reverse setting until i bound my controller to another car. (this car has steering, throttle and aux all in the normal positions). Thanks for reading.
11-03-2009, 08:19 PM
#25
Tech Addict
I wanted to add that just checking if the throttle linkage doesn't pulls on the entire motor might not be the complete method of setting your throttle linkage EPA. In addition to that, at full throttle you should be able to pull the throttle linkage out further an additional 1-2mm. If you can't and it doesn't pull back at all, you should back off another few clicks on your EPA so you have some play between full throttle on your transmitter and full mechanical throttle.
This is to compensate for chassis flex. If your pulling full throttle and there is no play, it will stress your servo when your chassis flexes, if the flex happens to be a twisting motion between the motor and the throttle servo. This can blow a servo over time.
This is to compensate for chassis flex. If your pulling full throttle and there is no play, it will stress your servo when your chassis flexes, if the flex happens to be a twisting motion between the motor and the throttle servo. This can blow a servo over time.
11-05-2009, 07:42 PM
#27
end-points... polarity
11-05-2009, 07:43 PM
#28
Thats what was wrong w/ mine anyway...
11-06-2009, 04:06 AM
#29
Tech Addict
Slayyer Had a losi and came over and asked if i had a servo horn for his hi-tec, I centered the servo and put on a new horn. the next thing i know is smoke came out of the servo.... he did not have the end points set properly and the servo horn I put on there was not gonna strip out like the other one he had, so it let the smoke out of the wires....I've never been able to put the smoke back in.Poof! Moral of the story never smoke your friends stuff ....always bring your own smoke!
11-06-2009, 04:28 AM
#30
Tech Fanatic
iTrader: (1)
Slayyer Had a losi and came over and asked if i had a servo horn for his hi-tec, I centered the servo and put on a new horn. the next thing i know is smoke came out of the servo.... he did not have the end points set properly and the servo horn I put on there was not gonna strip out like the other one he had, so it let the smoke out of the wires....I've never been able to put the smoke back in.Poof! Moral of the story never smoke your friends stuff ....always bring your own smoke!