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So I have a rc10 classic with a Novak t4 a Trinity 17 turn and warlock receiver. today I was trying to run the car for the first time with this new radio set up (it used to have a brushless system in it but I was really too much for the old 6 gear). So I plugged it in with a 3300mah 7.2 nimh and tested it on the bench everything worked so I took it outside. The very second I hit the throttle it ran away on its own(I had no control) for about 5sec then stopped lucky it didn't crash or anything so I walked and grabbed it. I tested it in my hand worked as it should so I set it down again and the same thing happened. My first idea was to swap out receiver and radio with 2.4 unit to see if the old receiver was shot. That did nothing so I took out the 2.4 unit and added a capacitor to the 75mhz one. That allowed me to drive it for about 5feet before it would go crazy. So I thought maybe the battery is the problem so I put the battery in my hornet which has vintage Traxxas esc in it and the battery worked fine in that car. So as a last try I decided, oh well let me at least try putting a lipo in it. What do you know with a lipo it works flawlessly. So I'm confused on what is going on here, anyone know?

When it goes crazy you are on the throttle?
If so....sounds like the bec voltage from that esc is low when on throttle, could be that nimh is falling off when on the throttle, or the esc is malfunction in the bec but the lipo keeps the voltage up enough to operate receiver.
All things pointing to bec in esc, at least in my opinion

I am on the throttle when it goes crazy and Bec was my best guess as well. I was wondering if you could wire in a separate Bec to the receiver, I've done this before with crawlers but I've always disabled the Bec on the esc with a programmer. So I don't know if having the esc Bec and an external one at the same time would hurt anything.

What servo are you running? modern servos draw allot more current than vintage servos.

Futaba S148 ~500 mA

Modern servo > 1000mA

you can add in a 4 cell battery pack to the reciever and pull the red wire from the esc connector. the receiver and servo will be powered from the 4 cell pack and the esc will power itself.

I have a super cheap servo it's a futaba s3004 nothing special and idk why I didn't think about the fact that I could just remove the red cable.

you will still need to power the radio and servo, so don't forget that.

beware actually, if you didn't get that futaba servo from a reliable vendor, it could be a clone or knockoff and could contribute to your issues.

Dr1rrrr wrote: ↑Wed Apr 01, 2020 11:27 am I have a super cheap servo it's a futaba s3004 nothing special and idk why I didn't think about the fact that I could just remove the red cable.

what could also happen is that your RC10 transmission is tight. When there is the load of moving the car on top, the voltage of your nimh drops below acceptable level and the BEC drops like crazy. On the hornet, it could be different because the transmission is fool-proof, so is the gear mesh. This is possibly why you saw a help with the condo on the rx which helped a few more ft.

try it with the car on a stand, but with you at a distance. if it still is "controllable" with the wheels in the air then it's the battery that cannot deliver enough current for the load. Watch the transmission and the battery then.

good luck and let us know
Paul