Hello! Log in or Register   |  Help  |  Donate  |  Buy Shirts  See all banner ads | Advertise on TheSamba.com  
TheSamba.com
 
Power Brake Booster Vacuum
Forum Index -> Water-cooled VW Share: Facebook Twitter
Reply to topic
Print View
Quick sort: Show newest posts on top | Show oldest posts on top View previous topic :: View next topic  
Author Message
runamoc Premium Member
Samba Member


Joined: June 19, 2006
Posts: 4032
Location: 37.5N 77.1W
runamoc is offline 

PostPosted: Fri Dec 07, 2018 8:08 am    Post subject: Power Brake Booster Vacuum Reply with quote

I've searched without out any luck. So I'll ask...for my '81 Mk1 Diesel...

I'm thinking I need either a new power brake diaphragm or just the whole power brake booster 'unit'. I rebuilt the vacuum pump. Second time in 2 years. I understand that's not abnormal. The brake pedal is still hard at first but the farther and the faster I drive it feels a little better. The check valve sounds free when I shake it. Could it be wore out? I replaced it 2 years ago when I did the first pump rebuild.

What different years and/or models of power brake booster/master cylinder combos will work on my 'ol smokey?
_________________
Daily driver: '69 Baja owned 38 yrs. Plan B: '81 Rabbit Diesel LS Deluxe
In garage for rehab: '72 Ghia - '71 Beetle
Out back: '69 Ghia - '68,'69,'70 Beetle - '84 Scirocco, GTI - Pair of '02 Golfs-
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
ps2375
Samba Member


Joined: April 24, 2014
Posts: 2279
Location: Meridian,ID
ps2375 is offline 

PostPosted: Fri Dec 07, 2018 8:24 am    Post subject: Re: POWER BRAKE BOOSTER VACUUM Reply with quote

Other than "shaking" the check valve, have you tested it?
Back to top
View user's profile Send private message Classifieds Feedback
TDCTDI
Samba Advocatus Diaboli


Joined: August 31, 2013
Posts: 6381
Location: North Carolina
TDCTDI is offline 

PostPosted: Fri Dec 07, 2018 9:42 am    Post subject: Re: Power Brake Booster Vacuum Reply with quote

Have you checked for vacuum leaks elsewhere in the system?

Disconnect the vacuum line going to the climate controls & cap the tap on the hose to the booster & see if the brakes feel better If so, then you have a leak in the climate system.
_________________
Everybody born before 1975 has a story, good, bad, or indifferent, about a VW.


GOFUNDYOURSELF, quit asking everyone to do it for you!
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Butcher
Samba Member


Joined: December 05, 2015
Posts: 787
Location: Right Here
Butcher is offline 

PostPosted: Fri Dec 07, 2018 10:10 am    Post subject: Re: Power Brake Booster Vacuum Reply with quote

Is it that hard to install a vacuum gauge and see where the vacuum is at? You could put a long rubber hose and see what's happening.

Knowing what the vacuum is, would certainly direct you to the problem fairly quick. If it is low, is it because of a leak or because there is not enough capacity?
Back to top
View user's profile Send private message Classifieds Feedback
runamoc Premium Member
Samba Member


Joined: June 19, 2006
Posts: 4032
Location: 37.5N 77.1W
runamoc is offline 

PostPosted: Today 8:18 am    Post subject: Re: Power Brake Booster Vacuum Reply with quote

Quote:
Disconnect the vacuum line going to the climate controls & cap the tap


My Rabbit has cable operated climate control 'flaps'. Straight from the pump to the check valve, then a 3/4" to 1/2" adapter with two 'taps', then the power brake servo.

Looking for leaks, I found the two rubber caps that fit over the two 'taps' in the adapter were dry-rotted and cracked. Found some 1" long screws that threaded right into the holes. Didn't have any rubber hose small enough to make a U connection. Snowing now will test this hack fix later. I'd still like to know what other VW power brake servo/MC combs could be 'swapped'. I've got some spare Mk4 parts.
_________________
Daily driver: '69 Baja owned 38 yrs. Plan B: '81 Rabbit Diesel LS Deluxe
In garage for rehab: '72 Ghia - '71 Beetle
Out back: '69 Ghia - '68,'69,'70 Beetle - '84 Scirocco, GTI - Pair of '02 Golfs-
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
Display posts from previous:   
Reply to topic    Forum Index -> Water-cooled VW All times are Mountain Standard Time/Pacific Daylight Savings Time
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

About | Help! | Advertise | Donate | Premium Membership | Privacy/Terms of Use | Contact Us | Site Map
Copyright © 1996-2018, Everett Barnes. All Rights Reserved.
Not affiliated with or sponsored by Volkswagen of America | Forum powered by phpBB