Cadillac & LaSalle Club Discussion Forum

Cadillac & LaSalle Club Forums => General Discussion => Topic started by: 914Driver on April 30, 2025, 04:12:51 PM

Title: What is this knob?
Post by: 914Driver on April 30, 2025, 04:12:51 PM
1940 LaSalle Series 52.  It only moves in and out, doesn't twist.  The wiper knob is up top, lights are to the right of this and I assume the dimmer for gages is in the headlight pull.

This one appears to have a metal to rubber vacuum line attached which runs to the fuel pump?

Wild guesses accepted.   ;D   (Sorry about the glare.)

Dan
(https://i.imgur.com/OPBUEps.jpg)
Title: Re: What is this knob?
Post by: Tom Boehm on April 30, 2025, 04:22:52 PM
This is not a guess, it is straight from the authenticity manual.
This knob controls the vacuum antenna on the driver side cowl. push in to raise and pull out to lower. The antenna is operated by vacuum just like the wipers. If yours does not work, I know a guy who restores those.



Title: Re: What is this knob?
Post by: 914Driver on May 01, 2025, 07:33:40 AM
Wow!  What Engineer 85 years ago sat with pen in hand after deciding that raising the radio antennae was a such pain in the butt?

Thank you Tom.


Title: Re: What is this knob?
Post by: Jay Friedman on May 01, 2025, 11:49:48 AM
Quote from: 914Driver on May 01, 2025, 07:33:40 AMWow!  What Engineer 85 years ago sat with pen in hand after deciding that raising the radio antennae was a such pain in the butt?

Thank you Tom.




I have a vacuum antenna on my '49 and I remember once asking myself the same question. 

My vacuum antenna has a mind of its own: most days it works but sometimes it just refuses to budge.  Every so often it won't work at all and I've found a cure is to squirt a bit of motor oil into the upper hose connection.  I've had to have it rebuilt twice over the years. 
Title: Re: What is this knob?
Post by: Tom Boehm on May 01, 2025, 12:28:46 PM
Hello 914, you were also uncertain about the dashboard light dimmer so I scanned in the whole page from the authenticity manual.
Title: Re: What is this knob?
Post by: tcom2027 on May 01, 2025, 12:42:03 PM
I've got a working antenna but am trying to find the correct knob for my'39 LaS.


tony
Title: Re: What is this knob?
Post by: Tom Boehm on May 01, 2025, 02:17:47 PM
tcom2027 I don't have either one. But, just to clarify, do you need the whole vacuum switch or just the plastic knob?
Title: Re: What is this knob?
Post by: The Tassie Devil(le) on May 01, 2025, 08:32:30 PM
But, if it was the Antennae controller, why would it have the Letter "L" on it?   L for Launch?   Or L for Lift?

Bruce. >:D
Title: Re: What is this knob?
Post by: Tom Boehm on May 02, 2025, 08:09:09 AM
Hello Tassie, I was confused at first about that also. The knob he was asking about was on the bottom of the dash above the parking brake handle.
Title: Re: What is this knob?
Post by: The Tassie Devil(le) on May 02, 2025, 09:02:16 PM
G'day Tom,

Thanks for the clarification.   I didn't even see that vertical knob initially.

Bruce. >:D
Title: Re: What is this knob?
Post by: tcom2027 on May 05, 2025, 09:00:14 AM
Quote from: Tom Boehm on May 01, 2025, 02:17:47 PMtcom2027 I don't have either one. But, just to clarify, do you need the whole vacuum switch or just the plastic knob?

Sorry for the delay in responding. I need the knob and switch.
Title: Re: What is this knob?
Post by: TJ Hopland on May 05, 2025, 07:45:14 PM
Did the antenna just lower when the vacuum dropped from shutting the engine off?  Or if you wanted it down did you have to think of that before you shut the engine off?
Title: Re: What is this knob?
Post by: Brad Ipsen CLC #737 on May 10, 2025, 10:31:47 AM
Works up and down only with the engine running.  Vacuum required going both directions.
Title: Re: What is this knob?
Post by: TJ Hopland on May 10, 2025, 10:56:49 AM
Would have been an interesting feature if it dropped with the engine off but I guess could have been a problem if you decided you wanted to listen to the radio with the engine off.
Title: Re: What is this knob?
Post by: harry s on May 10, 2025, 04:36:57 PM
Here's what the switch looks like. Sorry I don't have this one any longer.   Harry
Title: Re: What is this knob?
Post by: Barry M Wheeler #2189 on May 10, 2025, 05:38:58 PM
I'll be "Suzy Sunshine" and pass on that even 60 years ago, 1939 knobs were hard to find. I only had a 1939 Series 7519 for a short while as it didn't have an engine. It went to Detroit to help restore another car in need.

I'd towed it home from south of Indy with my 1941 Buick Century sedan. Stopped 12 miles from home at my Uncle's Shell station to get a Coke, and took a picture, but I've misplaced it. (It did look impressive as the dickens, with a smaller car towing that monster.)