Carburetor Related

Jeff Hookway

PCS Life Member
After returning from the Ohio meet with my 66 Superior ambulance last summer, the top repair item on my list was a carburetor rebuild.

Carburetor was rebuilt and received back and is on the vehicle. I’ve had the car out about a half dozen times since the rebuild. My fuel issues have been resolved. Runs good slow speeds, up and down hills.

Since then, two carburetor issues have occurred:

1. Sporadically the high idle does not kick down.
2. The transmission does not shift at the correct time. The first shift is around 25 mph, I’m ok with this. The second shift does not happen until about 48 mph. I did not have this problem prior to the rebuild.

The modulator valve has been replaced -- no change.
 
Jeff, I don't know if you are a member of the Cadillac & LaSalle Club. They have a very active forum that deals with a lot of mechanical issues. I think you can read them without a membership, but have to join to post or reply to a post. They also have a Chapter that is only for '63 and '64 models, with their own forum, and they have been extremely helpful to me with my '63.

I do recall reading a recent thread about the linkage between the transmission and carburetor and what adjustments have to be made. I had no idea they were interconnected until I read that post. I didn't pay too much attention to it since I don't have that issue with my car, but it was an interesting read anyway.
 

Daniel Scully

PCS Member
Site Supporter
66 Would be a turbo 400. modulator needs manifold vacuum to work correctly. Connected to the correct source? The governor has a nylon gear both could cause problems. Only thing controlled by the throttle linkage is kickdown / passing gear. Sounds possibly as two different issues. Did the trans work fine before the carb rebuild?
 

John ED Renstrom

PCS Member - Elected Director 2019-2022
I would check the vacuum hose from the vacuum modulator First. It may have a split end. The other problem could be the gasket has shrunk on the carb base or one of the other lines is split.
 

Paul Steinberg

Administrator
Staff member
Super Site Supporter
When you put the car into gear, does it lurch forward, or does it just stay put until you release the foot brake pedal" Is the engine idling smoothly?
 

Abe Bush

PCS Member
66 Would be a turbo 400. modulator needs manifold vacuum to work correctly. Connected to the correct source? The governor has a nylon gear both could cause problems. Only thing controlled by the throttle linkage is kickdown / passing gear. Sounds possibly as two different issues. Did the trans work fine before the carb rebuild?
Dan he did mention the transmission concern wasn't an issue until the carburetor was rebuilt.
 
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