1963 Riviera "Electro-Cruise" Speedo

[XframeFX]

Here I am in 2018 and researching yet another widget in my ride, the contact spring for the Electro-Cruise in my speedo.

Before I install it, I want to have it fully functional.  If I adjust the setpoint to 60 mph I have to move the speed pointer well past 60 to 110 mph before the spring contacts the oscillating pin. Below 110, the spring is 70 degrees from the pick-up arm. The notchless P/U Arm has no function from what I can see (spring slipped off?) The shop manual must be identifying the P/U Arm for a reason. The spring is not at all like what's pictured in the shop manual. More like a hair spring. It starts to de-form if I pull it more than 45 degrees towards the P/U Arm.

So, how does 1) Contact Spring 2) Oscillating Pin 3) P/U Arm relate to each other? Should the spring be held by the P/U Arm, if so, which side?

It would be nice to compare with another electro-cruise speedo to determine what's normal. Buicks so equipped had the same design up to model year 1967 before Cruise Master was used across all GM divisions.

 

Studying my fully functional parts speedo with only the speed buzzer, it has a different tang on its spring , exactly like what's pictured in the manual but is wound in the opposite direction obviously for contact closure above the setpoint. The P/U Arm has a notch to prevent the spring from slipping off. Moving the speed pointer, it works at the setpoint.

 

Does anyone know what the orientation of the contact spring should be? I can't see how it could possibly function the way it presently sits.

 

Thanks,

John B.

1964_Riviera_ElectroCruise_Speedo.pdf

[Dales90]

Hey, you're reminding me of my own experience in the 70s as I installed factory cruise on my 64. Biggest issue was drilling thru the brake pedal arm for the shut off pin, but I do remember the delicate contact spring in the speedo. Yes the cruise runs in the opposite direction from the speed sensor. I contimplated using a toggle to go between the two systems, never pulled that off.  Good luck!

[XframeFX]

Late '63 Riviera instrument harnesses were offered in at least 3 versions. Mine had the "green tab" which included power antenna, cornering lights and rear defogger. There were separate harnesses for power windows and "Electro-Cruise". So, yes, you could add it if you had all components. A/C was all under hood controlled from HVAC cables inside.

There's no aftermarket solution for anything to do with Electro-Cruise. Too bad, I figure I'm 85% there for a functional system. I'm even trying to understand the state of the contact spring from normal operation without ever being messed with. 1963 was the 1st year for the system so maybe it was never operational from the start. GM tweaked it for success by '64?

Looking for a 1964 140 mph Riviera Speedo with "Electro-Cruise"

Thanks for letting me think out-loud. If anyone has additional info/experience on this I'd appreciate all feed-back

John B.