Our 1986 Classic Newell has a throttle that sticks open and won’t back off to an idle. It happens randomly but pretty frightening when it occurs. Any thoughts on where to start? I was told it is an air operated device but have not confirmed. Coax #121. 8V92 engine. Allison four speed.
You might want to contact Stewart and Stevenson as they are a Detroit Diesel shop and seller.
I had a similar situation on my 87 with the 8v92. The throttle on mine is air & the actuator at the engine was a bendix unit that was basically an air cylinder with a flex cable attached that connected to the engine. That actuator assembly began reacting with more & more delay.
I replaced mine with a Williams WM388 throttle control cylinder and a bunch of custom fabricated mounts & brackets.
The factory cruise control no longer worked, so I installed a King Cruise unit (sadly, they are no longer in business).
I had similar, though not as severe , throttle issue .
The cable was frayed inside the housing , causing it to be slow to return to idle . As far as I know this cable is unobtainium. Sent cable to California Push /Pull( I think !)
.they rebuilt the cable, good job , reasonable cost and quick turn around . Not a great system , I have the parts to go to the system kyleb has , just haven't had the time to make brackets , etc .
Chris
Thanks to all for the insights!