ATE booster - Alfa Romeo Bulletin Board & Forums
 
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 08-20-2018, 09:24 PM Thread Starter
Registered User
 
goats's Avatar
 
Join Date: Jul 2006
Location: san diego CA
Posts: 5,083
ATE booster

Hi All

My 71 spider had an episode of 'hard brake pedal/ loss of efficient braking'. It was a two-off event, and I have not been able to replicate it other than to remove the vacuum line to the booster. Seems unlikely that I lost vacuum for those two events, car was running great and the hose is new, master is new, booster is what came with the car but seems to be working (mostly!)

So I pulled a ATE booster out of the cabinet to see if I could conjure up a scenario where this might occur, and I THINK I might have found one.

The booster has a metal rod that is firmly connected, and runs through a plastic cylinder (about 2 inches diameter) that sits on the pedal side. In order for the booster piston to travel in and out, this larger diameter rod passes through a seal on the pedal side, moves in and out, and the cylinder is actually what attaches to the diaphragm in the booster body.

If that large diameter cylinder got hung up (off angle and / or binding) we would have a stiff pedal. Seems logical and reasonable that the metal rod (concentric to the larger cylinder) needs to be free to move in and out of that seal,

The plastic cylinder is under the accordion boot on the pedal side. I wonder, should the OD of that cylinder be lubricated to make it easier to pass thru the seal, and to reduce any off-angle loading? If yes, what lubricant to use ? Seems to make sense again since the cylinder is under the accordion bellows and thus protected.

What say ye? Silicon based oil ? Teflon grease? I do think this is likely my issue on the spider as there is nothing else that moves except this rod/cylinder.

74 GTV with 10548's and Ingram pump
71 Spider 1750 BOMBER ; 1995 LS 78K tight fast car
goats is online now  
Sponsored Links
Advertisement
 
post #2 of 4 (permalink) Old 08-23-2018, 02:16 PM
Del
Senior Member
Gold Subscriber
 
Join Date: May 2005
Location: seattle
Posts: 15,232
Maybe ask in the Spider section. Some don't peruse much of the BB I suspect.

Del

Seattle

1989 Milano, Shankle Sport
1991 164S, stock
1994 164LS (~Q)
1972 Morgan 27

previously owned since 1964:

62 Morris MiniMinor 850, 67 Austin 1275 Cooper S (Downton 3/4 race), 64 Giulia Sprint GT (1st red one made), 72 Fiat 128 Sedan, 75 Alfetta Sedan, 78 Alfetta Sedan, 78 GTV, 81 GTV6, 86 GTV6
Del is offline  
post #3 of 4 (permalink) Old 08-25-2018, 07:55 PM
Member
Gold Subscriber
 
Chief's Avatar
 
Join Date: Jul 2014
Location: Sherwood, Arkansas
Posts: 79
Hi there, you can use a good silicone grease or just use some Dot-4 brake fluid. Use it sparingly, a little goes a long way. By the way, don't dismiss the vacuum check valve in the intake manifold. It can corrode inside and the spring can brake from rust. good luck, Chief

James (Chief) Bridges
J & J Racing, LLC,
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Chief is offline  
Sponsored Links
Advertisement
 
post #4 of 4 (permalink) Old 09-09-2018, 10:02 AM
Registered User
Platinum Subscriber
 
Andrew's Avatar
 
Join Date: Mar 2004
Location: Berkeley, CA
Posts: 20,818
That sounds like the air valve on the atmospheric end. I had one on a rebuild booster, sat on my shelf a long time and got a bit cruddy. Worked OK while engine ran but wouldn't close and hold vacuum afterward. Sent it back to the rebuild shop, they cleaned and lubed, all good.
It does take some effort to move the actuation rod from the pedal shaft, through the booster, to the MC. But you should be able to do it by hand.

Andrew
Andrew is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Alfa Romeo Bulletin Board & Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome