ESC & Servo problems
 

I went to the track today and drove my newly assembled Losi 8e 3.0 1/8th scale buggy and like I expected i had a lot of things to work out. I got most of them but however my servo and my esc are still acting up. My servo will NOT steer at all. It's fine when I first run the buggy but gets worse and worse the more it's ran..to the point the servo wolnt move at all. Meanwhile my ESC is running really low like something is draining the power from it. Just not sure what's going on. Thanks!

BTW here is what I'm running

ESC-Hobbywing Xerun SCT pro
Servo-HiTec HS-7955TG
Motor-Hobbywing Xerun brushless motor.

We need some more info to be able to help you.
What ESC?
What Motor?
What Battery?
What Servo?
What is your gearing?

Yeah I did update the post. I have a 43t spur and 14 pinion

If you ask me I would say you need an external BEC or a glitch buster, the servo drains the ESC's internal BEC for power and that resulting in the loss of power to the servo and/or RX.
So the ESC is trying to keep up with the constant drain on the BEC it just makes a vicious draining circle. Even though the HiTec HS-7955TG "only" munches 6V it might still be too much for the ESC to handle. When you have the car on your setup stand and you flip the wheels rapidly from side to side does it slow down in movement or cut out entirely?

A glitch buster would perhaps do the trick since it's not a HV servo but having the external BEC in hand as an option might be wise.

I have a CC 10A BEC in my Durango DEX408 where I have a Tekin RX8 ESC and an Xpert WR-6601 servo and it works perfectly.

A good external BEC like the Castle Creations 10A BEC which you can program to give out exactly as much power to the RX as the servo is made to opperate on.
Remember if you do want to use a CC BEC and want to be able to program it you will also need the Castle Link.

Well at first it slows down in movement but the more I flip the wheels side to side is just doesn't even turn. I have a programmer that I'm going to hook up to my esc and change some settings. Thank you a lot for the info and advice. I'm going to look into the external BEC.

Is the buggy always fine when you start running it? After how long of driving does it start acting up?

Do you have your end points on your radio set correctly? If you're going lock to lock, the servo can pull a lot of power when it stalls. That servo pulls 4.2A at lock/stall and the BEC in that ESC is only 3A.

As Hitokiri mentioned, you'll probably need a external BEC.

Start with the simple things, recalibrate your end points for the ESC, bench test the Servo on an amp meter make sure it's not pulling more current than it should, adjust your servo end points so it's not trying to push the steering further than it should. Check your plugs / sensor leads etc make sure nothing is loose.

Does it do the same thing with a different servo?

Yeah its always fine when I start running it. After about 3-5 minutes I start to lose turn. Yeah I'm pretty sure I have my end points set correctly but I will look at them again.

That's something I haven't done. I'll get an amp meter and test it to see what it's pulling. I haven't tried another servo, I actually don't have another one but I might get another one and see if that fixes it. Can a brand new servo right out of the box be junk? I guess not necessarily junk but be messed up I guess?

I'd also suggest disconnecting the link to the servo and testing the steering by hand to see if there's any binding or other resistance. Try it with the front wheels off the ground. They should turn fairly easily by manually using the servo linkage.

What's strange is the 3-5 minutes. How's your battery? If you run for 3-5 minutes, shut everything down wait a while and start again. Does the issue start immediately? Trying to eliminate the battery and it's voltage as a culprit.

Even a top notch servo can have a flaw/malfunction right off the shelf but it's rare.

Try the various things Gerry suggests and see if there's anything that binds the steering or maybe there's something inside the servo it self causing binding or other issues. if all seems to be in order, then try a glitch buster or external BEC for starters and see if that don't fix the problem.

After the few minutes of running when the servo acts up, is the servo warm/hot?

Yeah It gets pretty warm

I did try that GerryH and there was some rubbing/resistance there But I have fixed that. When I shut it off and wait a while everything is fine but then it acts up again.

That sort of eliminates the battery being an issue.

Is it warm or hot? Warm is probably normal, hot is not.

I think you've somewhat eliminated all the obvious potential issues. Hitec is known for their customer support, you might want to email them.