I'm trying to get an old RC boat working as a lockdown project with my daughter. I had all the parts from ~25 years ago, and have just bought an ESC motor controller from Amazon. The receiver is a Futaba FP-R112JE. The new ESC controller successfully powers up the receiver, and the servo to control the rudder works. But the wires to the motor just seem dead. The motor doesn't turn at all as we use the throttle, and I can't measure any DC voltage across the wires. I'd first assumed this was a faulty ESC, but have bought another ESC and have the same problem. Perhaps is a compatibility issue with the signal wire from the receiver? Digital vs. old analog? What am I doing wrong? I've also tried swapping channels - both receiver channels work with the servo. Thanks in advance!
Can't post the Amazon link for the ESC, but the full product name is "6-12V 320A High Voltage ESC Brushed Speed Controller for RC Car Boat". Also tried to post a photo but the forum wouldn't let me yet, can try and send if it would help.

You will need to calibrate the esc to your radio. There may be instructions for this if your esc came with a manual, but likely you’ll need to turn it on while holding the button on the switch, then pressing the button to lock in the neutral, full throttle and full brake points while leaving the throttle at the right position.

Also, I which battery are you using?

That's great, thank you, I will try that. It didn't come with any instructions.
I'm using an old 7.2V NiCd battery, and have also tried wiring it up to 4xAAA batteries. Both successfully power up the ESC and receiver, just nothing from the motor yet.

make sure no throttle trim b4 calibrating new esc. you should be able to find a manual online and calibrate esc.. good luck

Did you contact Amazon about a missing manual?

Did yo try to search for one, probably this will work:
https://downloads.absima.com/english...-4-ENGLISH.pdf
It hs th same jumpersetting so I asume it is from the same manufacturer.

2nd search, based n the model number on the side of the case:
https://cdn.simba-dickie-group.de/do..._Regler_en.pdf

?

A 320A ESC for $20. With no Waterproofing?

4 AAA batteries is only 6v. Less if they are rechargeable. You need 5 to get the correct voltage.

Thanks everyone for your help, much appreciated. Now have a happy daughter!
It was a voltage issue. 4xAAA (non-rechargeable) was 6V and just on the 6-12V it said it needed, but still not enough. And I guess the old 7.2V NiCd battery wasn't really giving out 7.2V, at least not when loaded.
Didn't chase Amazon for a manual, but those links were really helpful, thank you. I think it is the same model or very similar. Also helps me figure how to control it now it powers up the motor.
Eventually I tried 6xAA batteries and it worked! Will now look at getting a more suitable battery.
"A 320A ESC for $20." - I don't think it's a very high quality one :-)

The other issue you may be facing is related to A feature of the esc called lipo cutoff, which is why I asked about the battery. Most modern esc’s come set up to work for lipo batteries which will put out 8.4V (4.2 per cell) and are usually designed do best to cut off at around 6.4V-7V. Your older pack may dip below this cutoff voltage quickly, causing the esc to stop. This is designed to protect lipo batteries that don’t like being run down too low. You should disable the cutoff voltage for your nicad battery and stop as soon as you notice a significant loss of speed.

That's helpful, thank you. I really don't want it cutting out or I'll be swimming to recover it :-)