Brake servo question

Tigerneeds

Bronze forum user
Messages
8
I did a quick search and couldn't find the answer for my question.

Can someone explain to me why I have seen several Tigers with the brake servos and some without? I know this should be obvious to me, but on a recent '66 MKI-A there was no servo. I'm kinda new but I thought all Tigers had that part. Is it placed somewhere else or ?
 

cobrakidz

Gold forum user
Messages
2,289
All Tigers came with them, most Tigers had them go bad, some Tigers decided to go without afterwards. I have had 6 Tigers and only 2 had them, there is better braking with them but it's not that bad without...and look how much extra room you have without it. :)
The usual problem is that the diaphragm in the unit goes bad and then it makes a good paper weight.
 

michael-king

Gold forum user
CAT Member
Messages
4,132
As stated all tigers and aloines from 3 onwards have servos , there are 5 and 7" versions. Both have their issues. Also not many people rebuild them correctly so often after a rebuild they are sticky, pulse or inconsistent so people ditch them and just change to a different note m/c like on the si/ii alpines. Some also change the rear wheel cylinders as well .
 

Tigerneeds

Bronze forum user
Messages
8
Thank you guys very much. I thought I was correct when I looked at a Tiger Saturday at a show. I know the owner very well and he has an impressive collection of all types of cars (65). He had purchased the Tiger through an auction two years ago. His wife doesn't like to drive it and he is too large for the car. He offered it to me at $60K and I declined. It will go back to auction next week. The car has been tac'd but it is clear that the data plates had been removed and replaced with the wrong rivets. I noticed no booster however the car does include several LAT options. I am looking for a strong, completed car that I can drive verses spending time doing a restoration. I have two projects now that will be sold to fund a driver. Both Tigers, one un-restored original and my damaged one will be offered as soon as I can get them on the lift for photos.
 

Erich

Gold forum user
Messages
148
The stock booster only works with a single bowl master cylinder. If somebody wants the safety of a dual bowl mc, they have to give up the booster.
 

HolyCat

Gold forum user
CAT Member
Messages
1,241
Smitty Can Replace Leather in Diaphram

The usual problem is that the diaphragm in the unit goes bad and then it makes a good paper weight.

In a recent edition of the Tiger Tales there was an article about Smitty in San Diego rebuilding servo units. It shows him replacing the leather seal in the diaphragm.
 

65beam

Gold forum user
CAT Member
Messages
1,827
servo

the brake booster can be used with a dual master cylinder. sunbeam did this starting in 1968 when they switched to Lockheed boosters and Lockheed dual brake master on the alpine fastback. the booster was only connected to the front wheel brakes. has anyone tried this on a tiger?
 

0neoffive

Gold forum user
CAT Member
Messages
2,853
Saw One

the brake booster can be used with a dual master cylinder. sunbeam did this starting in 1968 when they switched to Lockheed boosters and Lockheed dual brake master on the alpine fastback. the booster was only connected to the front wheel brakes. has anyone tried this on a tiger?

I know of one single line Girling servo with a tandem master (3/4" Subaru unit) on a Tiger. I re-built the servo for the owner who told me later that he used a slightly larger rear cylinder in order to keep the hydraulic work efforts in balance. This makes sense in hydro math, but I have no idea what type of rear pistons he had used (lost further contact with him).
 

65beam

Gold forum user
CAT Member
Messages
1,827
brake servo

randy,
my fastback has 7/8 " wheel cylinders on the rear brakes.
 

mr55s

Gold forum user
CAT Member
Messages
330
Brake servo

I was wondering if anyone has a 7" Girling brake booster "valve body" that is rebuildable they would be willing to part with. I appreciate anyones help on this.
Brian
 

0neoffive

Gold forum user
CAT Member
Messages
2,853
A few Odds & Ends

I was wondering if anyone has a 7" Girling brake booster "valve body" that is rebuildable they would be willing to part with. I appreciate anyones help on this.
Brian

Got a sweet relined #92 (7") valve body at the ready and a couple more at the machinist. Also just finished and tested a 7" MK2B unit; a bit more reliable than the MK2A critters. Send PM, etc.
 

Attachments

  • MK 2B 7 inch servo.jpg
    MK 2B 7 inch servo.jpg
    223.8 KB · Views: 214

Hoghead

Gold forum user
Messages
570
Do TR6's not have the booster on the fronts only?

Back in the day I rebuilt my own servo......
My Healey has just eaten its second servo, so it is currently by-passed and going to be changed to dual circuit

I have now decided to go with dual circuit MC on the Tiger, and size the hydraulics appropriately, using a proportioning valve on the rear. A bit of math involved to get the leg force reasonable, but there are on-line calculators to help figure it out

My application has rear discs using larger Lincoln callipers on 10.4" Mustang Cobra rotors to match the Wilwood fronts, so not applicable to all.
The hydraulic sizing exercise is common to all applications

I intend to write an article on how I did the rear brake mod and the logic behind sizing the hydraulics
 

Warren

Gold forum user
Messages
3,872
White post

What was the name of that special restorer of hydraulics. Found it.. http://whitepost.com/
I have more 7" in storage but can't get to any fun project's or be a helpful hoarder.
I've seen several requests for these items lately across Tiger postings on different boards. It'd be a top vote I bet for a poll.
" What stopped the Tiger in it's tracks?"

You know what made the car undriveable and get parked then the dust collector then the first few boxes transforms to car into a garage shelf.

One of our directors had one fail on his way to meeting..

Robert the logic you mentioned is clear.
What's the warranty on a rebuild ? The same as a new clutch slave...
Not to hijack but I've been meaning to get a couple re sleeved too.
 
Last edited:

0neoffive

Gold forum user
CAT Member
Messages
2,853
Remaining restorers

What was the name of that special restorer of hydraulics It's http://whitepost.com/
I have more 7" in storage but can't get to any fun project's or be a helpful hoarder.
I've seen several requests for these items. It'd be a top vote I bet for a poll.
" What stopped the Tiger in it's tracks?"

You know what made the car undriveable and get parked then the dust collector then the first few boxes transforms to car into a garage shelf.

One of our directors had one fail on his way to meeting..

Robert the logic you mentioned is clear.
What's the warranty on a rebuild ? The same as a new clutch slave...
Not to hijack but I've been meaning to get a couple re sleeved too.

Warren: Apple Hydraulics does a fair job of re-lining in brass and smoothing the air horn seats. We use him when we are backed up. The downside is they DO NOT bevel the power valve bore and the lip seal will flip when installed, making it useless. We have to bevel it as a matter of assembly (not easy). There also was a guy in Sierra, CA but now retired. rw
 
Last edited by a moderator:

Warren

Gold forum user
Messages
3,872
Thanks RW

The vendors should be added to the White pages listing's
As for being backed up my Doc says get more fiber :D

I have added Tags to make the thread more searchable. If anyone wants tags added or a vendor added to the members only White pages area let an Admin know.
 

Too Tech

Bronze forum user
Messages
40
Not sure this is 100% on topic; BUT
If your booster seems to offer uneven braking with respect to how hard you push the pedal, or if the foot pedal force does not seem linear with actual braking action, Try cleaning and then re greasing the 5 or 7" bore with grease intended for a High Vacuum application.
Mine seems to need this treatment once a year to keep my braking smooth and linear with foot pressure.
 
Top