Welcome to the THE H.A.M.B. forums.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

Go Back   THE H.A.M.B. > General Discussion > The Hokey Ass Message Board

Reply
 
Thread Tools Display Modes
Old 06-14-2012, 06:58 AM   #1
LesIsMore
Grenade Inspector
 
LesIsMore's Avatar
 
Join Date: Apr 2008
Location: Ohio
Posts: 368
Default Adjusting Hydraulic Brakes 39 Ford

Ok, so blakes are bled, I have a pedal, but its spongy, seems the brakes need adjusting. The worm/shell gear whatever you want to call it obviously gets tighter/looser as you rotate it, however is there a good rule of thumb for how they "Should" be set? I am starting at completely free rolling, all of the way loose, i always go for the slightest drag of shoes, is this the way to go, or do you guys have some advice?

Les
__________________
Design is genius in its purest form.
27 T Modified
28 Ford Model A
52 Buick Special
offline   Reply With Quote
Old 06-14-2012, 07:35 AM   #2
HellRaiser
Senior Member
 
Join Date: Jun 2006
Location: Podunk, NE
Posts: 1,242
Default Re: Adjusting Hydraulic Brakes 39 Ford

If you are using original 39 brakes, I would suggest you take the drum off one and see how they operate. I could explain it here, and I'm sure others after me will chime in and try to tell you, but once you see how they operate, then adjusting them will become a whole lot easier.


HellRaiser
offline   Reply With Quote
Old 06-14-2012, 08:10 AM   #3
LesIsMore
Grenade Inspector
 
LesIsMore's Avatar
 
Join Date: Apr 2008
Location: Ohio
Posts: 368
Default Re: Adjusting Hydraulic Brakes 39 Ford

I have had them all apart and rebuilt them, I am just wondering how I should adjust them, front shoe and back shoe have own adjuster, should all be loose, moderate, tight, etc. Should the front shoe or back shoe adjustmenst be equal, etc.
__________________
Design is genius in its purest form.
27 T Modified
28 Ford Model A
52 Buick Special
offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 06-14-2012, 08:28 AM   #4
Saxon
Senior Member
 
Saxon's Avatar
 
Join Date: Aug 2008
Location: FL
Posts: 1,934
Default Re: Adjusting Hydraulic Brakes 39 Ford

I have to pull my drums on my truck this weekend to do what your asking.

I like to have a slight drag, then back it off one click. You don't want them freewheeling imho.

Also, on the later with the spoon adjuster. We always did adjustment by lifting car, spinning tire, and adjust till the shoes just started to drag. All wheels.
offline   Reply With Quote
Old 06-14-2012, 08:38 AM   #5
Saxon
Senior Member
 
Saxon's Avatar
 
Join Date: Aug 2008
Location: FL
Posts: 1,934
Default Re: Adjusting Hydraulic Brakes 39 Ford

Also you could have the shoes grind arched to drums. If needed.

http://fordbarn.com/forum/showthread...t=arched+shoes
offline   Reply With Quote
Old 06-14-2012, 08:45 AM   #6
George/Maine
Member
 
George/Maine's Avatar
 
Join Date: Jan 2011
Location: Mid Coast, Maine
Posts: 954
Default Re: Adjusting Hydraulic Brakes 39 Ford

you may want to try this way.
Remove drum center shoes bottom equal amount,now expand to 1/8 less then drum
12 -11 7/8 if they hit on top grind off whats in way.
That should get you good to go close enought.
offline   Reply With Quote
Old 06-14-2012, 09:29 AM   #7
LesIsMore
Grenade Inspector
 
LesIsMore's Avatar
 
Join Date: Apr 2008
Location: Ohio
Posts: 368
Default Re: Adjusting Hydraulic Brakes 39 Ford

Saxon,
I do the same thing, getting it in the air seems to be best way, ok, than I have it right, have to look at lines and M/C next.
__________________
Design is genius in its purest form.
27 T Modified
28 Ford Model A
52 Buick Special
offline   Reply With Quote
Old 06-14-2012, 11:25 AM   #8
JustplainJ
Member
 
JustplainJ's Avatar
 
Join Date: Apr 2007
Location: so.cal.
Posts: 914
Default Re: Adjusting Hydraulic Brakes 39 Ford

don't forget about the top adjuster's.......lots of guy's only do the bottoms.
start with the back shoes then go to the front with slight drag at all four drums.... if pedal is still spongy you have air in sys.or another problem
this is how I do mine pedal is very firm......
__________________
Rat ROD MY ASS! IT'S A HOT ROD.
offline   Reply With Quote
Old 06-15-2012, 12:12 AM   #9
fordor41
Member
 
fordor41's Avatar
 
Join Date: Jul 2008
Location: elmira, new york
Posts: 616
Default Re: Adjusting Hydraulic Brakes 39 Ford

Quote:
Originally Posted by JustplainJ View Post
don't forget about the top adjuster's.......lots of guy's only do the bottoms.
start with the back shoes then go to the front with slight drag at all four drums.... if pedal is still spongy you have air in sys.or another problem
this is how I do mine pedal is very firm......
alternate between the top and bottom adjusters with some pressure on the brake pedal.
offline   Reply With Quote
Old 06-15-2012, 12:37 AM   #10
JohnEvans
Old School HAMBer
 
Join Date: Apr 2008
Location: Phoenix AZ
Posts: 4,813
Default Re: Adjusting Hydraulic Brakes 39 Ford

Hate to say it ,but do a search. The 39-42 style with the bottom adjustable anchors take a very specific adjusting sequence for proper operation. And if your drums are over .040 OS and the shoes were not arced to the drum even with the correct adjustment you likely will have a spongy pedal until the shoes get seated.
__________________
Ya can't have toooo many tools or DOGS !!
offline   Reply With Quote
Old 06-15-2012, 01:01 AM   #11
Dirty Dug
Old School HAMBer
 
Dirty Dug's Avatar
 
Join Date: Jan 2003
Location: Edmonds,Wa,USA
Posts: 3,171
Default Re: Adjusting Hydraulic Brakes 39 Ford

I don't like bad answers. You're on the right track having them all loose. Adjust the bottoms first till they just start to resist then back off just a hair. Then adjust the tops until they do the same...You're done, further adjustments as brakes wear will be just the tops. What you have are excellent front brakes for a light hot rod. Don't ever let anyone tell you you need to upgrade to discs for better braking...
offline   Reply With Quote
Old 06-15-2012, 02:03 AM   #12
striper
Old School HAMBer
 
striper's Avatar
 
Join Date: Mar 2005
Location: Central Vic, Australia
Posts: 4,404
Default Re: Adjusting Hydraulic Brakes 39 Ford

********************** BRAKES **********************
‘39 THROUGH ’48 FORDS AND MERCS: These brakes were designed by
Lockheed. Hydraulic pressure expands the wheel cylinder cups which
push the shoes against the drum. The shoes are NOT self-energizing.
The Lockheed system is a front/rear shoe design with the bottom pivot
for each shoe firmly anchored to the backing plate. These require
considerably more pedal pressure to stop than self energizing brakes
because they rely solely on hydraulic pressure. The front shoes do
most of the stopping and use the longer friction band. The rear shoes
have the shorter friction band.
‘39-’48 LINCOLNS (and ‘49 and up Ford/Merc): These are
manufactured by Bendix. They are self energizing (often referred to
as duo servo) brakes. The shoes are linked to each other at the
bottom, but are not attached to the backing plate like the Lockheed
design. The system is a primary/secondary shoe (not forward/rear)
design. The primary is the front shoe in all wheels. The top of the
primary shoe is moved outward by hydraulic pressure to contact the
drum. The rotation of the drum “wedges” against the primary shoe and
moves it downward. Since the bottom of the shoes are not attached to
the backing plate, this movement is transmitted through the bottom of
the secondary shoe. This force moves the bottom of the secondary shoe
outward where it now “wedges” into the drum. This increases braking
and decreases brake pedal effort. This results in considerably more
braking force than the sheer hydraulic pressure design used in the
earlier Lockheed brakes. Since the Bendix uses self energizing
action, the primary (front) shoe has the shorter friction band and the
secondary (rear) shoe has the longer friction band.
F-100 BRAKES FOR EARLY FORDS: These are Bendix brakes.
Conversions require drums, backing plates, and hubs from a ‘53-’56
Ford F-100. These drums use the same large bolt wheel pattern as the
‘40 through ‘48 Fords do. One pair of Timken 14116 inner bearings,
one pair of CR Services 15214 oil seals, and both ‘37-’48 Ford
spindles are needed. The ‘39 through ‘41 spindles have a round flange
and require modifying because the wheel cylinder won’t clear the
spindle flange. Grind off the top of the flange that interferes with
the wheel cylinder. The ‘42-’48 spindles have a somewhat square
flange which clears the wheel cylinder and grinding is not required.
On both round and square flanges, the new inner bearing has a square
shoulder which conflicts with the rounded race on the spindle. Grind
the inside of the bearing race to round it slightly so the bearing
will fit snugly against the spindle’s mounting face. Every thing else
is a bolt up.
EARLY WIRE WHEELS ON ‘40 THROUGH ’48 DRUMS: When using early
spoke wheels, spacers are needed between the drum and the wheel
because the early drums have a taper where the wheel meets the drum.
The ‘40-’48 disc wheels did not have this taper. If the drums are
bolted up without the adapter, the drum won’t be seated tight against
2
the drum and all force is transmitted directly to the wheel lugs...
not a good thing.
SQUEAKING BRAKES: Squeaking can be caused by oil or brake fluid on
the brake linings. But squeaking can also be inadequate lubrication
in some locations. Put a small film of grease, or a single drop of
oil, wherever the metal part of the shoe contacts anything metallic.
This includes; the shoe to backing plate rub points, where the
emergency brake cable connects to the actuating arm, the emergency
brake actuating arm pivot pin and wave washer, where the emergency
brake cable exits the cable’s housing, the brake shoe holding pins and
washers, and wherever the springs etc. come into contact with the shoe
or backing plate.
An old trick we used to use was to stretch a screen door spring
around the brake drum to dampen drum vibrations. This worked.....
sometimes.
If your brakes have been in use for some time and they begin
squeaking, try going over the linings with 80 grit sand paper to
remove any glaze. Just scuff them enough to break the glaze.
************************* ADJUSTING BRAKES *********************
ADJUSTING ANCHOR PINS ON ‘39 THROUGH ’48 FORD/MERC BRAKES: These
are Ford Lockheed (not Bendix) brakes and use special brass washers in
conjunction with eccentric anchor bolts to position the shoe. The top
of the shoes are controlled by eccentric cams. The anchor bolts at
the bottom of the backing plate control the shoe position by rotating
eccentric washers at the bottom of the shoes. Make sure the anchor
bolts turn freely.
‘39-’41: These anchor bolts have locating marks indented on the
elongated head adjusting bolt. These anchor bolts extend through the
backing plates and are adjusted externally after loosening their large
external lock nuts. The elongated " head has either a punched dot or
a stamped arrow for reference when making anchor adjustments. After
adjusting the shoes, the adjustor lock nuts are tightened without
permitting rotation of the anchor pin adjusters.
‘42-’48: The anchor pins are essentially the same as the ‘39-’41
brakes but do not have any reference marks. But, unlike the ‘39-’41
brakes, the lock nuts are located internally on the inside of the
backing plate. The large round bolt heads on the outside of the
backing plate have no dots or stamped arrows, but have a plain round
head (similar to a carriage bolt). The drum must be removed to
loosen/tighten the anchor adjustor’s lock nut and to adjust the anchor
pins. Removing the drums to adjust the anchors is next to impossible
during brake shoe adjusting (the top adjusters have to be adjusted so
the wheel cannot be turned). It’s a lot easier if a groove is ground
across the rounded head for a bladed screwdriver. Then a screwdriver
can be used on the outside as a substitute for the 1/4" elongated bolt
used on “39 through ‘41 models. After adjusting, The drum has to be
removed to tighten the anchor pins lock nuts.
Always rotate the wheel in the same direction the wheel turns as the
car moves forward.
3
(1) Slightly loosen both anchor bolt lock nuts on one wheel. On ‘39-
’41, turn the 1/4" adjuster so the locator marks on the two shoes face
each other. On ‘42-’48, remove the drums and turn the anchor pins so
the wide part of their brass washers face each other and re-install
the brake drum.
All further adjustments are made by turning the anchor bolt
adjusters in a specific direction.....
(a) The front anchor bolt adjusters on both wheels on the
drivers side are turned counter-clockwise (looking at the back side of
the backing plate)...... the rear anchor bolt adjusters are turned
clockwise.
(b) The front anchor bolt adjusters on both wheels on the
passenger side are turned clockwise (looking at the back side of the
backing plate)......... the rear anchor bolt adjusters are turned
counter-clockwise.
(2) Back off the upper 11/16" cams on both shoes until the drum turns
freely.
(3) Turn one of the upper adjusting 11/16" cams until the wheel
cannot be turned. Then adjust its 1/4" anchor bolt in the correct
direction until the wheel turns (this lowers the shoe and moves the
toe of the shoe away from the drum which will result in fuller shoe
contact).
(4) Now repeat previous step (3) over and over on the same shoe until
turning the anchor bolt will not free-up the wheel.
(5) Back off the anchor pin very slightly until the wheel will just
barely turn. Tighten the anchor pin lock nut and proceed to the
backing plate’s other shoe before going on to the next wheel.
TIP: If you’re installing new shoes which have been arc-ground
to fit a newly turned drum, you normally won’t have to go through the
preceding exercise. Turn the dots/arrows on ‘39-’41 models (or the
wide part of the brass washers on ‘42-’48 models) until they’re facing
towards each other. This correctly positions the brake shoes and you
don’t have to go thru the anchor pin adjusting..... just adjust the
upper 11/16" cam adjusters.
***************** WHEEL & MASTER CYLINDERS *****************
WHEEL CYLINDERS ON FORD LOCKHEED BRAKES: Because these brake
systems rely solely on hydraulic pressure to push the shoe against the
drum, the shoes which have the longer frictional bands need more
pressure than the shoes with the shorter amounts of frictional
material. Most Lockheed wheel cylinders use two different sizes of
cups. The larger size cup is for the forwardmost shoe (longest
friction band).
HONING: Honing wheel and/or master cylinders during rebuilding is
critical. Use of cutting oil in place of kerosene or solvent when
honing hydraulic cylinders will produce a superior surface in
considerably less time. The hone scores made using cutting oil
provide a much better sealing surface than when using solvent or
kerosene. Be sure to thoroughly clean the cylinder after honing.
4
BLEEDING A REPLACEMENT MASTER CYLINDER. This is used only when
replacing a master cylinder. Because all of the air is usually
located at the master cylinder’s fitting connections, it will often
bleed back into the master cylinder with a little coaxing.
Top off the master cylinder and install the cap. Pump the brake
pedal about 10 pumps quickly (it’ll be close to the floor). Then
allow air to dissipate for a minute or so. Repeat another 10 pumps
and wait. Top off the brake fluid. Repeat it once more. After the
third time, the air should have bled off and you should have a firm
pedal. If you don’t have a firm pedal, try it a couple more times.
If you don’t have a firm pedal, there is air elsewhere in the system
and you’ll have to bleed the whole car. Beats jacking up the car and
bleeding each wheel. If you’re going to flush the system you get to
bleed all four wheels.
SILICONE BRAKE FLUID: Neat stuff and it doesn’t eat paint. I
don’t use it except in something that’s primarily a show car.
Reasoning? I find the brake pedal feels softer than when using
regular DOT 3 brake fluid. Also, the Rocky Mountains where I live,
have some fairly high mountain roads and passes. And for some reason
I don’t know, frequent and/or abrupt altitude changes will often cause
the silicone brake fluid to become somewhat cloudy because it’s
absorbed a very minute quantity of air. This makes for a soft brake
pedal that may go clear to the floor. After the car sits for a few
hours, the air dissipates from the silicone and the pedal returns to
its former status and feel. If I’m hauling it at speed into a neat
corner (we all play don’t we?) I sure get nervous if the brake pedal
feels spongy or like it’s going away..... my heart can’t stand too
much excitement anymore! However, many use silicone with absolutely
no problems. As with all this garbage, this is just my opinion.
(From rodnut on 1/30/03: Another problem is it will damage the
diaphragm in hydraulic brake light switches. Use a mechanical type
brake light switch.)
BLEEDING A DRUM/DISC BRAKE SYSTEM: If you’re running a
combination brake system (disc front and drum rear) you’re probably
using a proportional valve to limit hydraulic pressure to the rear
brakes. Bleeding this type of system is different than bleeding an
all-drum system. The proportional valve for the drums shuts down when
it senses any pressure in excess of the proportional valve’s pressure
setting. Consequently we can’t just have a buddy stomp on the brake
pedal and bleed the system. Pressure brake bleeders are mostly
limited to 15 psi to keep from activating a proportional valve or
metering valve. If you don’t have a pressure bleeder, have your buddy
push the brake pedal gently (like with only his big toe) so the pedal
applies very little pressure while you bleed the system.
SOFT BRAKE PEDAL ON A DISC/DRUM BRAKE SYSTEM: Sometimes after
you’ve worked on either the disc or drum brakes the pedal is soft and
feels like “it’s going away” when stopping. Scary isn’t it? The
cause is often the rear drum brakes are out of adjustment. Especially
5
if you’re just converting to front disc brakes. Adjust these puppies
fairly snug and see if it doesn’t help the pedal.
A disc brake rubber flex hose expands considerably due to high
hydraulic pressure unless it’s new or in top shape. Some come with
multi-bands of steel wrapped around them to strengthen them. Have a
buddy stomp on your brake pedal hard when your hand is wrapped around
your rubber flex hose. Does it expand? One cure I use (instead of
replacing it with another new rubber hose) is to use a steel braided
flex hose. These are usually cheaper than a stock Ford rubber flex
hose and help firm the brake pedal.
************************** BRAKE DRUMS *************************
PULLING A BRAKE DRUM WHEN A PULLER IS NOT AVAILABLE. These can
try the patience of any man. The following is certainly not intended
to replace a correct puller, but it’s saved me several times when the
correct tools weren’t available.
I use a bumper jack and the weight of the car to help break the drum
loose. Let’s say you want to pull the right brake drum. Get the car
on a reasonably level surface and block both ends of both front wheels
to prevent forward or backward motion. Release the emergency brake
and take it out of gear. Leave the right side wheel bolted to the
drum and remove the right axle nut and washer. Invert the nut and put
it back on the axle sans washer (don’t want to pound on the
castellated part) until it’s flush with the axle end. Jack up the
left rear side of the car with a bumper jack. Get it high enough so
the left rear wheel is off the ground a few inches. Grab a hand
sledge hammer (to persuade the drum to loosen). Go back to the right
rear wheel. Plant your butt against the fender or body and lean
against the car. Lean hard enough so it feels like it’s about to rock
off the bumper jack. Then hit the axle nut a few times while you’re
leaning hard against the car. The tipping weight of the car pulls
against the right wheel that is still on the ground. The drum will
usually come loose after only a few healthy swings. And if the
flathead gods are smiling down on you, you didn’t damage the axle
threads so bad that a couple of swipes with a file won’t cure.
INSTALLING AN EARLY REAR BRAKE DRUM: When installing a rear brake
drum on a ‘48 and older car, wipe a light coat of anti-seize compound
on both the axle taper and the key. This makes future drum removals a
lot easier. Tightening the axle nut is covered in the GEAR SECTION of
this garbage pile
__________________
VULTURES
Australia

http://www.readersdigest.com.au/most-trusted-professions-2013
offline   Reply With Quote
Old 06-15-2012, 02:04 AM   #13
striper
Old School HAMBer
 
striper's Avatar
 
Join Date: Mar 2005
Location: Central Vic, Australia
Posts: 4,404
Default Re: Adjusting Hydraulic Brakes 39 Ford

The above, as far as I know, is courtesy of Bruce Lancaster.

Pete
__________________
VULTURES
Australia

http://www.readersdigest.com.au/most-trusted-professions-2013
offline   Reply With Quote
Old 06-15-2012, 02:14 AM   #14
nailhead29A
Member
 
nailhead29A's Avatar
 
Join Date: Sep 2010
Location: New Zealand/ Western Australia
Posts: 795
Default Re: Adjusting Hydraulic Brakes 39 Ford

Holy shit Striper thats a 101 on Ford brakes, just putting a set in my car at the moment so that info couldn't have come at a better time.
Thanks for posting
offline   Reply With Quote
Old 06-15-2012, 03:21 AM   #15
fredeuce
Member
 
fredeuce's Avatar
 
Join Date: Jan 2009
Location: A shed somewhere in South Central, Australasia
Posts: 508
Default Re: Adjusting Hydraulic Brakes 39 Ford

Have a look at this previous thread. In particular the Service Bulletins that set out the procedure.

http://www.jalopyjournal.com/forum/s...ghlight=brakes
offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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 On

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 05:23 AM.