Cadillac & LaSalle Club Discussion Forum

Cadillac & LaSalle Club Forums => Technical / Authenticity => Topic started by: dbzsjones on April 26, 2025, 04:58:25 PM

Title: Brake booster washers flat or lock?
Post by: dbzsjones on April 26, 2025, 04:58:25 PM
I just got my booster back from Karps Power Brake Service, and it looks great, but it came back without the mounting hardware. Off to the store for 4 3/8-24 nuts, but should I be getting flat or lock washers?
Title: Re: Brake booster washers flat or lock?
Post by: Clewisiii on April 26, 2025, 06:56:50 PM
Mastercylinder to booster. Split washer. 20250426_185500.jpg
Title: Re: Brake booster washers flat or lock?
Post by: dbzsjones on April 27, 2025, 07:45:14 PM
  I wasn't specific enough, I'm looking for what goes behind the firewall and holds the booster to the firewall.
Thanks,
Del
Title: Re: Brake booster washers flat or lock?
Post by: Clewisiii on April 27, 2025, 08:32:12 PM
I cannot remember if these are the same nuts that hold the entire brake pedal assembly to the firewall. That is packed away. I might be able to get a glimps in my parts car. But the inside is trashed right now.
Title: Re: Brake booster washers flat or lock?
Post by: TJ Hopland on April 28, 2025, 10:56:16 AM
Later I think it was common to use the type where the toothed washer is part of the nut. Not sure if those had a name, I suspect the name depended on the brand. 
Title: Re: Brake booster washers flat or lock?
Post by: dbzsjones on April 28, 2025, 03:37:59 PM
The booster came back with 1 of the 4 nuts on it and it was a normal nut, but it could have been whatever the rebuilding had lying on the bench to make sure the threads were clean after the plating.
Title: Re: Brake booster washers flat or lock?
Post by: Clewisiii on April 28, 2025, 06:44:56 PM
I see no washers on the inside.

20250428_180446.jpg20250428_180940.jpg20250428_180953.jpg
Title: Re: Brake booster washers flat or lock?
Post by: TJ Hopland on April 28, 2025, 06:49:01 PM
Looks like what I always heard called a 'Stover locknut'.   I would guess thats a brand name, not sure if they are still around or not.   
Title: Re: Brake booster washers flat or lock?
Post by: Clewisiii on April 28, 2025, 06:53:45 PM
Stover nuts can still be found. Just not everywhere. Uses a deformation in the thread to lock in place.


20250428_185229.jpg
Title: Re: Brake booster washers flat or lock?
Post by: dbzsjones on April 29, 2025, 10:19:28 AM
Stover lock nut no washer it is, thanks for the help!
Given the location and visibility of the nuts, and availability considerations, I may settle for a nylock nut.
Title: Re: Brake booster washers flat or lock?
Post by: 59-in-pieces on April 29, 2025, 11:35:18 AM
Del,

Here is a close-up of the interior nuts and toothed washer used in a 59.
Hope this helps.  (expand the picture to see the teeth more clearly, but they are there)

Have fun,
Steve B.
Title: Re: Brake booster washers flat or lock?
Post by: 35-709 on April 29, 2025, 10:04:54 PM
Quote from: TJ Hopland on April 28, 2025, 10:56:16 AMLater I think it was common to use the type where the toothed washer is part of the nut. Not sure if those had a name, I suspect the name depended on the brand. 

They do have a name, they are called KEP nuts, you can Google that name on the internet and get a large variety of same.  FWIW, if that were my booster, I would use flat washers and nylock nuts.  Not a big deal unless it is a show car and you think the judges will look under the dash to see what kind of fasteners you used.   :)
Title: Re: Brake booster washers flat or lock?
Post by: tcom2027 on April 30, 2025, 10:25:31 AM
Quote from: TJ Hopland on April 28, 2025, 10:56:16 AMLater I think it was common to use the type where the toothed washer is part of the nut. Not sure if those had a name, I suspect the name depended on the brand. 


Flange or flanged nut.

tony
Title: Re: Brake booster washers flat or lock?
Post by: dbzsjones on April 30, 2025, 10:36:48 AM
Thanks all, not a show car so not worried about a judge sticking his head under the dash, just wanted to make sure I attached it appropriately.  So it looks like locking nuts are the theme, with a preference for KEP or Stover.  I do have a latent AR tendency that wants to get things as close to authentic as possible even if it's not a show car.
Title: Re: Brake booster washers flat or lock?
Post by: 59-in-pieces on May 01, 2025, 01:08:10 PM
Del,

The toothed washer is OEM - and cheaper, but who am I to get involved in such a life changing, earth shaking decision.

Have fun,
Steve B.
Title: Re: Brake booster washers flat or lock?
Post by: dbzsjones on May 02, 2025, 09:27:20 PM
Cheaper and more accurate!  How often does that happen in this hobby?  Must be my lucky day.