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Bill roberts box


Well-known member
Turtle runs a old Roberts box.

They have some rotational noise but I would not say it’s loud.

Move the prop back and forth with power off to see if you have excessive lash in your gears. Also pull and push on the output shaft checking for movement.

It has been several year since last Roberts box was seen over my way. I used to have a number for a guy who worked on them in South FL but it’s not there any more.

Maybe one of the other members has a point of contact.

That said for Cadillac in my opinion the Torque or Rotator with soft drive plate is the drive of choice should you need to replace it.

They made 1:53 and 1:77 for stock and mild upgraded engines. Kwan has my old 1:53 from back in the day.


Try what Swamp recommended above. The link below has a crude drawing of how the box bolts to the adapter & motor.

I would make sure to the check the flywheel, adapter, all nuts & bolts are tight and change the gear oil. (check for wear metal)

Carmotor gearboxes can start making a racket due to cracked flywheels.



Well-known member
Loose flex plates or broken flexplates happen. Especially if years back the builder drilled out a factory plate. We run SFI certified plates today on the commercial drives and I have seen some Stinger users with a Billet plate.

We use LocTite on the flex plate bolts and torque to spec. Think we use 50 lbs as the setting.

terrible ted

Well-known member
Thats my Drawing I scratched it out on the counter. The gear box makes a clickety clack noise I love. Need a vent tube and oil - any aircraft oil or equivalent. Nothing special about the box itself it's the mounting plates that are special. Really almost any Lycoming aircraft gear box would of bolted up to my old setup