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  • March 28, 2024, 04:44:32 AM

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Author Topic: Smaller Power Brake Booster  (Read 1002 times)

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Offline OverKnight

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Smaller Power Brake Booster
« on: September 22, 2020, 07:43:16 PM »
Hello - My son and I are detailing the engine bay of his 1986 Eagle.  We just pulled the master cylinder and power brake booster out to clean and paint the firewall and the booster itself.  It was a real chore to remove the booster; due to interference from the inner fender, I literally had to use a pry bar to remove it.  There's no way we're going to clean and paint the booster, firewall and inner fender and be able to reinstall it without scratching all of the paint off.  Does anyone know of a smaller booster that would fit in an '86 Eagle?
Thank you.
"I shall pass through this world but once.  Any good I can do, or any kindness that I can show any human being, let me do it now and not defer it, for I shall not pass this way again."
- Stephen Grellet

Offline Canoe

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Re: Smaller Power Brake Booster
« Reply #1 on: September 24, 2020, 01:00:50 PM »
Which '86 Eagle?
I've changed the booster on my '86 wagon, and it was a pain, but not like you describe.

I don't think changing for a smaller booster is a good idea. I'd assume that it may mean less booster power, or fewer brake uses if the engine fails, or both.

Is it possible that someone stuffed a larger booster in there to try and give it better braking?

Offline OverKnight

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Re: Smaller Power Brake Booster
« Reply #2 on: September 24, 2020, 09:49:11 PM »
Thanks, Canoe.  It's a 1986 Eagle Limited with the 4.2 L engine and automatic transmission, soon to be 4.0 L stroker.  I don't know if this is the stock booster or not.  The engine is out of the car, so we had lots of room to work, except where the lower left section of the booster was hitting the inner fender.  I don't believe there's a direct correlation between booster diameter and the force the booster creates.  If I can't find a suitable smaller booster, I'll probably massage that section of the inner fender in by about 1/4".
"I shall pass through this world but once.  Any good I can do, or any kindness that I can show any human being, let me do it now and not defer it, for I shall not pass this way again."
- Stephen Grellet

Offline Canoe

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Re: Smaller Power Brake Booster
« Reply #3 on: September 25, 2020, 12:05:36 AM »
I've got the Wagon. As an '86, yours would be a Wagon or a Sedan.

Strange. I switched my booster with the engine, manifolds and carb still in place. It was a pain, but it did fit.
I wonder if they switched in a different part due to a shortage on the production line that day/week/etc..

If your engine fails, that booster is the reservoir for power braking. I'm not liking the sounds of reducing that.

Offline OverKnight

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Re: Smaller Power Brake Booster
« Reply #4 on: September 25, 2020, 11:41:22 AM »
My son's car is also a wagon.  If the engine dies, there's enough vacuum in the booster for maybe two stabs of the brake pedal.  I don't know enough about these to make authoritative statements, but I have read about instances, I believe with hot rods, where a smaller booster was installed, with no reported decrease in braking power.
"I shall pass through this world but once.  Any good I can do, or any kindness that I can show any human being, let me do it now and not defer it, for I shall not pass this way again."
- Stephen Grellet

 

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