Author Topic: Early Vacuum booster  (Read 4989 times)

p3aflyer

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Early Vacuum booster
« on: September 15, 2019, 11:52:05 AM »
Does anyone know what make and model number the early vacuum brake booster is?  Has anyone ever rebuilt one?  any rebuild kits Available. 

R.E.Co.

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Re: Early Vacuum booster
« Reply #1 on: September 15, 2019, 04:43:35 PM »
From what I understand, no rebuild kits are available which is why you don't see them anymore.  The original ones were also  very touchy and sometimes failed.  Best bet is to bite the bullet and install a new modern hydro vac for reliability sake.  Good luck!
1941 White M2
1941 Chevrolet G506 Civilian Dash
1941 Federal 94-43 4-5 Ton COE
1918 3 Ton Field Gun Trailer

p3aflyer

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Re: Early Vacuum booster
« Reply #2 on: September 15, 2019, 06:24:52 PM »
Thanks for the info .  I might have to go with the more modern hydrovac  or even a modern replacement.  I was just curious about who made it and if any parts or leather seal might be available? There is not much to  them really.    I am planning on rebuilding it anyway just for kicks.   Any parts from other rebuild kits will save me some time fabricating them. 

yd328

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Re: Early Vacuum booster
« Reply #3 on: September 17, 2019, 05:22:43 AM »
If I am talking about the same hydrovac, which I believe is the second design, there is a seal between the vacuum and brake fluid that goes bad. There are one or two companies that have them figured out. They are about $750-1000 to have rebuilt by them from what I have heard.

Gary

p3aflyer

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Re: Early Vacuum booster
« Reply #4 on: September 17, 2019, 08:21:21 AM »
The vacuum booster I am rebuilding used an fork and rod assisting a fork and lever to help compress the master cylinder rod.  So the booster is basically a second series internal engine vacuum actuated booster.  In theory isn’t near as good as a hydrovac. Which from what I understand  it can be very costly to rebuild certain models. 

What I don’t know about the vacuum brake pedal assist booster is who made it?  My guess is Bendix? If so what’s the model number? And lastly maybe a rebuild kit for another model or hydrolvac style booster that the parts , seals, might fit? Really the only thing that i need to get right is the leather dyaphram  seal and the little rubber internal plunger ? Which can be made from a rubber coated washer.


R.E.Co.

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Re: Early Vacuum booster
« Reply #5 on: September 18, 2019, 08:14:51 PM »
I have an early M2 which is supposed to have the same brake assist. I wasn't able to find one, and mine was missing it.  So that being said, no luck for me.  Even if you did rebuild yours, for safety on the road and ensuring you stop without issue, I'd replace it and make an adapter using the same four hole pattern from the rear mounting bracket.  Thats what I did.  For how much my track will be around other people, I dont want to take a chance the original style, even if rebuilt, failed because of poor design. Thats my 2 cents. 
1941 White M2
1941 Chevrolet G506 Civilian Dash
1941 Federal 94-43 4-5 Ton COE
1918 3 Ton Field Gun Trailer

p3aflyer

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Re: Early Vacuum booster
« Reply #6 on: September 18, 2019, 08:45:10 PM »
I appreciate your imput.  All good advice.  My track is so far from being around other people and driving on public roads and participating in parades  etc!!    I am not worried about safety issues , stopping it , at this point.  My barn find track now runs but is far from being driven anywhere.   I'm being the ten year old kid playing with an army halftrack !!  just having fun with it and learning as much as I can about it.  With the right adjustments and proper rebuild I'm sure it will work just fine.  I have no ambition to cruise the parade circuits just yet .   This booster unit  I believe is a bendix made product but all of my halftrack info does not address it other than detailed  rebuild!!  Funny it states if worn etc, just replace with new!! Lol, if only!! 

I have a source  for these units if anyone wants to try to go this route?  I completely understand not wanting the early unreliable unit but for those that are purist there is a way!!   

What's the old saying?   Once made by man , it can can be made  new again!!

yd328

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Re: Early Vacuum booster
« Reply #7 on: September 19, 2019, 07:13:43 PM »
Looking in my ORD-9(December 1944) supply book it looks like the manufacturer was Bragg-Kliesrath (B-K). Maybe an earlier supply book would have some more part information. It looks like there are some companies that deal with them.

Gary

p3aflyer

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Re: Early Vacuum booster
« Reply #8 on: September 21, 2019, 11:32:23 PM »
Gary !! That’s really good info. I was way off with what I had thought about the booster .  I big thank you for this new information.

It turns out there are  some replacement parts for these things!!