NESC-4 with a stuttering problem

[markbt73]

I got an old Novak 4 (not T4) ESC in trade recently. It works perfectly when the car is on a stand, wheels under no load, but when I put the car on the ground it just stutters at full throttle. At very light throttle it will move, but as soon as I give it more power it stutters again. Pick up the rear tires, floor it, and it revs up just fine.

As I know nothing about these old ESCs I was hoping someone on here could help me out. Parameters: installed in an RC10CE with a 19 turn Reedy "Mr N" motor and fairly conservative gearing, and running off an old 6 cell 1500 NiCd pack, running on pavement. It came with a Tamiya connector included, so I used it. Motor is hardwired and has all capacitors installed.

Is it too much motor for this ESC? Doesn't seem like it would be... Is the connector not allowing enough current? I run other cars with equivalent motors with Tamiya connectors with no problems. Is it just 25 year old technology that's on its last legs? I hope not... I would kind of like to use it.

Any help would be appreciated.

[8rad]

That sounds really similar to the problem I had a while ago. The fact that it is only happening under load suggests the speedo is not getting enough juice. You should be fine with a 19T and Tamiya connector.

I would open the speedo and check the condition and solder job on the battery/motor wires as a start.

[Lonestar]

running off an old 6 cell 1500 NiCd pack

Here's your culprit right here... that pack is dead and doesn't supply enough current under load.

Paul

[8rad]

You're probably right Paul. Try a new battery first!

[markbt73]

I'll try a better battery, but the same battery and motor work fine with a different ESC between them. I guess I'll take the bottom cover off and check the solder connections. Are the wires replaceable on these old ones? The ones on there have been spliced; I'm wondering if that's restricting current.

[8rad]

They are replaceable but dont try unless you are proficient with a soldering iron. It is very easy to overheat the pads. If that happens then it will be very difficult to repair. Take my word for it.