Please help, brake booster question

[Abomination 0]

Hey guys, really stuck. I swapped brake boosters and the old one has a symetrical circle for the pushrood, new one has a hockey stick shaped pushrod.

It bolted up fine and looks identical and everything works great, only issue is the brake light switch wont fit on the hockey puck shaped pushrod. Does that booster have a different switch or am I being crazy?

Pictures are just quick screenshots from the internet and not my brake boosters, but the pushrods look like these two

[Mach1 Driver 528]

Many places sell brake boosters but they are the wrong ones for our cars. There are several videos by West Coast Classic Cougar on the correct boosters and where to get them rebuilt, or you can buy a rebuilt from them. I would recommend a rebuilt over a new one. He discusses the differences here also:

https://www.youtube.com/watch?v=MbW_v_DdEuU&t=50s

Here are some resources:

1.    Boosterdeweyexchange.com

 2.    Chockostang is a highly recommended rebuilder of steering components and he recommends: Midwest Remanufacturing

 3.    The old Global West GM recommends: Karps Power Brake Service

 4.    Harmon Classic Brakes

[Brian Conway 255]

Generally speaking for an original system; the curved arm is for a 69 and the straight arm is for the 70.  The brake switch fits onto the brake pedal post. The switches can be for manual brakes or power brakes.  Brian

[Abomination 0]

So I already switched it and don't really want to do double work, it was a pain in the butt.  Is there a brake switch that fits the curved arm?  Searching the 69-70 brake switches look the same?  Thanks in advance guys

[RPM 1,157]

Welcome to the forum, what year is your Mustang?

 

[Abomination 0]

1970 base convertible.  And thank you

[jjstang 50]

My 69 has the curved one. But that’s no help for a 70. 

[Brian Conway 255]

NAPA shows two switches' available one for Power Brakes Echlin SL201 and one for Manual Brakes Echlin SL200.  Most venders don't describe the difference.  Brian

[det0326 172]

On 9/10/2023 at 12:26 PM, Abomination said:

So I already switched it and don't really want to do double work, it was a pain in the butt.  Is there a brake switch that fits the curved arm?  Searching the 69-70 brake switches look the same?  Thanks in advance guys

Sorry but i think you would be a world ahead to change the booster now with the correct one. The 69 as u know is offset making the pushrod pivot point  different and the pushrod is not aligned straight. Not saying it won't work but it will soon wear the vacuum seal. 

[ThePoose 31]

Repeating some of the same here. The booster shouldn't affect the switch, but maybe you got a manual switch for an auto (or vice versa)? The price difference between the two is pretty significant if I remember right. Even though it works, the booster you have will likely fail sooner than later. How soon will likely depend on how much you drive your car. Definitely watch that WCCC video to understand why, or just for all around knowledge. Brakes will still work, so no worries. And if you do decide on a rebuild of one, thumbs up for Booster Dewey.

[kblagron 14]

I have a 70 manual trans  that did not have a brake booster when I bought it, but did originally.  I bought a Scott Drake brake booster for a 70 Mustang,  and it had a different shaped pin than the original booster had, and I had an issue with the brake light being on all the time.  I compared a photo of the original  .vs. what I had, and it was apparent that I needed to shave some of the pin to get the brake light to not be engaged.  It took me a few iterations with a Dremel tool to shave enough of the pin so that the brake light would turn off, but really wasn't that hard.  The photo shown has the booster installed in my car with the pin off of the pedal on the left, and the one on the right is what it should look like.  I shaved off the end of the pin and got it working.