Brake Caliper Rebuild Questions

Caroline, Rex,

Thanks for the info...

Randall Fox

 

"brake fluid is the recommended lube _if you don't have silicone handy_"

yes, there's a number of products like you mention. the important thing
is NEVER to use a normal grease - complete ruination.

 

"brake fluid is the recommended lube _if you don't have silicone handy_"

yes, there's a number of products like you mention. the important thing
is NEVER to use a normal grease - complete ruination.

 

Good one for the archives, Jim, particularly about where to apply the silicone
grease.

I couldn't quite get the pistons back in with thumb pressure. It sure didn't
take much force from the C-clamp (and I was on the lookout for applying the
force incorrectly, watching for tilting of the piston as I tightened the
C-clamp), so I'm not concerned.

More for the archives:
I think I bled each wheel altogether twice more. (Helluva workout in the last
few days. Makes me think about buying a hydraulic jack lift.) I used a different
Mityvac bleeder valve adaptor on the rear brakes and got the vacuum from the
Mityvac pump to hold better. Still, I never got the fairly solid stream that I'd
get at the front brakes. OTOH, I had teflon tape on the front bleeder screws
from the get-go. I never removed the (all rusty) rear bleeder screws. Next time
I do a bleed, I will replace the rear bleeder screws and teflon tape them.

It seemed like the brakes were still a tad mushy, but I was not sure. Thus the
extra bleeds. Then after more study I read that mal-adjusted rear brakes might
very well imitate air in the system. I couldn't find the "star wheel adjuster"
the first time I cleaned up the rear brakes last week and so hadn't touched it
on either side. I went at it again yesterday. Bustard technical manual Chilton
technical writers say simply that the adjuster is "located on the inboard side,
underneath the control arm." That's like saying the PCV valve is in the engine
compartment... somewhere...

I googled and someone wrote about his/her trailer brakes and how they have
little rubber plugs that have to be removed to get to the "star wheel adjuster."
Majestic's site indicated the existence of such an "adjuster plug" on the rear
brakes (as well as the adjuster). Someone else's Usenet post commented about how
the plug was on the inboard side of the brake backing plate. Someone else said
to use a flashlight to see it.

All true.

The plug is at about the 1 o'clock or 11'o'clock position (depending on the
car's side) on the inboard side of the drum brake's backing plate. If one really
wants to see the star adjuster well, skip the flashlight and take off the drum.

Overall, I had more luck making the adjustment with the drum off than through
the plug hole. Of course, one has to keep fitting the drum over the shoes etc.
to see how the fit is.

The star adjuster wheel itself is just a little 1/2-inch diameter or so gear or
circular ratchet.

The results of my rear brake adjustments: Noticeably less mush in the brake
pedal. I think it's better than when I first began this adventure, though I'm
still suspicious that my sloppiness in bleeding the brake system (the "gulp" at
the MC reservoir) led to more air than is desirable in the system. The parking
brake is much tighter, too.

The last time the rear brakes were adjusted must have been when I had the rear
brake shoes replaced, four years ago, around 112,000 miles.

 

Good one for the archives, Jim, particularly about where to apply the silicone
grease.

I couldn't quite get the pistons back in with thumb pressure. It sure didn't
take much force from the C-clamp (and I was on the lookout for applying the
force incorrectly, watching for tilting of the piston as I tightened the
C-clamp), so I'm not concerned.

More for the archives:
I think I bled each wheel altogether twice more. (Helluva workout in the last
few days. Makes me think about buying a hydraulic jack lift.) I used a different
Mityvac bleeder valve adaptor on the rear brakes and got the vacuum from the
Mityvac pump to hold better. Still, I never got the fairly solid stream that I'd
get at the front brakes. OTOH, I had teflon tape on the front bleeder screws
from the get-go. I never removed the (all rusty) rear bleeder screws. Next time
I do a bleed, I will replace the rear bleeder screws and teflon tape them.

It seemed like the brakes were still a tad mushy, but I was not sure. Thus the
extra bleeds. Then after more study I read that mal-adjusted rear brakes might
very well imitate air in the system. I couldn't find the "star wheel adjuster"
the first time I cleaned up the rear brakes last week and so hadn't touched it
on either side. I went at it again yesterday. Bustard technical manual Chilton
technical writers say simply that the adjuster is "located on the inboard side,
underneath the control arm." That's like saying the PCV valve is in the engine
compartment... somewhere...

I googled and someone wrote about his/her trailer brakes and how they have
little rubber plugs that have to be removed to get to the "star wheel adjuster."
Majestic's site indicated the existence of such an "adjuster plug" on the rear
brakes (as well as the adjuster). Someone else's Usenet post commented about how
the plug was on the inboard side of the brake backing plate. Someone else said
to use a flashlight to see it.

All true.

The plug is at about the 1 o'clock or 11'o'clock position (depending on the
car's side) on the inboard side of the drum brake's backing plate. If one really
wants to see the star adjuster well, skip the flashlight and take off the drum.

Overall, I had more luck making the adjustment with the drum off than through
the plug hole. Of course, one has to keep fitting the drum over the shoes etc.
to see how the fit is.

The star adjuster wheel itself is just a little 1/2-inch diameter or so gear or
circular ratchet.

The results of my rear brake adjustments: Noticeably less mush in the brake
pedal. I think it's better than when I first began this adventure, though I'm
still suspicious that my sloppiness in bleeding the brake system (the "gulp" at
the MC reservoir) led to more air than is desirable in the system. The parking
brake is much tighter, too.

The last time the rear brakes were adjusted must have been when I had the rear
brake shoes replaced, four years ago, around 112,000 miles.

 

I thought that star wheel, in between the two clevis pins, was supposed to
be turned by the self-adjusting lever??

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

 

I thought that star wheel, in between the two clevis pins, was supposed to
be turned by the self-adjusting lever??

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

 

True. For example:
_____
Most modern drum brakes are designed to self-adjust during application when the
vehicle is moving in reverse. This motion causes both shoes to rotate very
slightly with the drum, rocking an adjusting lever. The self-adjusters are only
intended to compensate for normal wear. Although the adjustment is "automatic,"
there is a definite method to actuate the self-adjuster, which is done during
normal driving. Driving the vehicle in reverse and applying the brakes usually
activates the automatic adjusters. If the brake pedal was low, you should be
able to feel an increase in the height of the brake pedal.
-- from Chilton's and Autozone's site for circa 1991 Civics, "Brake Operating
System: General Description"
_____

In addition, as I'm sure you're aware but for the record, parts drawings
identify the "self-adjuster lever" etc. that operates the star wheel adjuster.

But also --

1.
Chilton's and Autozone give a procedure for manual adjustment of the rear
brakes. It's under the "Adjustments: Rear Drum Brake Adjustment." I assume
manual adjustment is for 'non-normal wear.'

2.
Googling for {star wheel adjuster} or similar words on adjusting rear brakes
turned up some posts that talked about limitations in the self-adjusting
mechanism. IIRC someone (or two) claimed that you had to drive in reverse,
brake, then drive forward a little and do this repeatedly (to get enough turns
on the star wheel adjuster) to get a good adjustment. The persons(s) said it was
easier and more reliable to do the adjustment manually.

3.
_____
On vehicles with rear drum brakes, mis-adjusted brake shoes can cause a "long"
pedal and reduced braking, giving the illusion of air in the lines. If you're
trying to track down such a problem, adjust the rear brakes and test drive the
car before bleeding the system.
--from Chilton's and Autozone, "Bleeding the Brake System," typed in bold, right
before the first step for bleeding.
_____

I am a bit concerned I overtightened the shoes such that they are too close to
the drums. Guess this will just wear the shoes quicker. Also, I can't say I'm
100% confident the self-adjusting lever is doing its job. It seems a flimsy
design that doesn't hold the star wheel all that securely, so as to achieve only
the one-way rotation that should occur as the brake shoes wear.

OTOH, the star wheel adjuster wasn't that easy to turn in either direction. (I
pulled the lever out a little to rotate the star wheel adjuster such that the
shoes didn't press against the drum, as I was experimenting.)

I did put a couple of drops of "PB Blaster" on the star wheel adjuster-bolt
threads, where it mates to the clevises, as best I could, trying to minimize the
stuff getting onto anything else. This seemed to help.

Again, this is the first time I've ever personally (1) bled, and ultimately
effectively flushed, the brake system and (2) removed the rear drums and "brake
cleanered" the rear brakes' guts. I will certainly consider further commentary
on my approach here.

 

True. For example:
_____
Most modern drum brakes are designed to self-adjust during application when the
vehicle is moving in reverse. This motion causes both shoes to rotate very
slightly with the drum, rocking an adjusting lever. The self-adjusters are only
intended to compensate for normal wear. Although the adjustment is "automatic,"
there is a definite method to actuate the self-adjuster, which is done during
normal driving. Driving the vehicle in reverse and applying the brakes usually
activates the automatic adjusters. If the brake pedal was low, you should be
able to feel an increase in the height of the brake pedal.
-- from Chilton's and Autozone's site for circa 1991 Civics, "Brake Operating
System: General Description"
_____

In addition, as I'm sure you're aware but for the record, parts drawings
identify the "self-adjuster lever" etc. that operates the star wheel adjuster.

But also --

1.
Chilton's and Autozone give a procedure for manual adjustment of the rear
brakes. It's under the "Adjustments: Rear Drum Brake Adjustment." I assume
manual adjustment is for 'non-normal wear.'

2.
Googling for {star wheel adjuster} or similar words on adjusting rear brakes
turned up some posts that talked about limitations in the self-adjusting
mechanism. IIRC someone (or two) claimed that you had to drive in reverse,
brake, then drive forward a little and do this repeatedly (to get enough turns
on the star wheel adjuster) to get a good adjustment. The persons(s) said it was
easier and more reliable to do the adjustment manually.

3.
_____
On vehicles with rear drum brakes, mis-adjusted brake shoes can cause a "long"
pedal and reduced braking, giving the illusion of air in the lines. If you're
trying to track down such a problem, adjust the rear brakes and test drive the
car before bleeding the system.
--from Chilton's and Autozone, "Bleeding the Brake System," typed in bold, right
before the first step for bleeding.
_____

I am a bit concerned I overtightened the shoes such that they are too close to
the drums. Guess this will just wear the shoes quicker. Also, I can't say I'm
100% confident the self-adjusting lever is doing its job. It seems a flimsy
design that doesn't hold the star wheel all that securely, so as to achieve only
the one-way rotation that should occur as the brake shoes wear.

OTOH, the star wheel adjuster wasn't that easy to turn in either direction. (I
pulled the lever out a little to rotate the star wheel adjuster such that the
shoes didn't press against the drum, as I was experimenting.)

I did put a couple of drops of "PB Blaster" on the star wheel adjuster-bolt
threads, where it mates to the clevises, as best I could, trying to minimize the
stuff getting onto anything else. This seemed to help.

Again, this is the first time I've ever personally (1) bled, and ultimately
effectively flushed, the brake system and (2) removed the rear drums and "brake
cleanered" the rear brakes' guts. I will certainly consider further commentary
on my approach here.

 

i know it's frequently cited here, and it's not your fault, but imo,
reversing to adjust the rear drums is in the same league as using the
emergency brakes to adjust them - complete rubbish. anyone that's
watched the adjuster mechanism in action with the drum removed can
easily see how it works - there's no black magic or art involved - they
are designed to self-adjust in normal operation.

that said however, adjustment /does/ depend on the adjuster wheel being
free to rotate. if it's rusted, clogged or screwed in too tight [say
after new shoes have been fitted], it won't work and the assembly needs
to be stripped down, cleaned, lubed & reassembled. i also find that a
little manual pre-adjustment helps get the ball rolling. the adjuster
can then be heard clicking on release after each time the brake pedal
has been pressed hard. just keep operating the brake until the clicking
stops. then you should have a great feeling pedal and good brakes.

 

i know it's frequently cited here, and it's not your fault, but imo,
reversing to adjust the rear drums is in the same league as using the
emergency brakes to adjust them - complete rubbish. anyone that's
watched the adjuster mechanism in action with the drum removed can
easily see how it works - there's no black magic or art involved - they
are designed to self-adjust in normal operation.

that said however, adjustment /does/ depend on the adjuster wheel being
free to rotate. if it's rusted, clogged or screwed in too tight [say
after new shoes have been fitted], it won't work and the assembly needs
to be stripped down, cleaned, lubed & reassembled. i also find that a
little manual pre-adjustment helps get the ball rolling. the adjuster
can then be heard clicking on release after each time the brake pedal
has been pressed hard. just keep operating the brake until the clicking
stops. then you should have a great feeling pedal and good brakes.

 

Both of above sound like Chilton's "generic advice" again.:-(

The Honda/Helm manual for a '90 Civic describes the procedure for changing
rear brake shoes and the final step says to press the brake pedal to set
the self-adjusting mechanism.

Yeah I've never been convinced that a self-adjusting mechanism, as
implemented, can work effectively in the environment it lives in after a
few years of lubricant burn-off, clag and corrosion build-up. If there's
any drag, it's easy to check the drum temps after a drive.

At least the Honda drums are easy to get off - I recall my Beetles which
needed a 250ft-lb torque wrench to get the rear axle nut off.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

 

Both of above sound like Chilton's "generic advice" again.:-(

The Honda/Helm manual for a '90 Civic describes the procedure for changing
rear brake shoes and the final step says to press the brake pedal to set
the self-adjusting mechanism.

Yeah I've never been convinced that a self-adjusting mechanism, as
implemented, can work effectively in the environment it lives in after a
few years of lubricant burn-off, clag and corrosion build-up. If there's
any drag, it's easy to check the drum temps after a drive.

At least the Honda drums are easy to get off - I recall my Beetles which
needed a 250ft-lb torque wrench to get the rear axle nut off.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

 

Not true as a general statement. I have personally owned cars that were
specifically designed to only adjust the brakes when stopping in reverse
(anything GM from the 60s & 70s), and I have personally owned cars that only
moved the adjuster when the parking brake was set. I have also owned cars
with rear drum brakes that maintain adjustment in normal usage ('02
Pathfinder). Some don't even have an adjusting wheel, they use a sliding
wedge. Calling it all rubbish is rubbish. You have to look at the
mechanism used by the specific manufacturer to correctly answer this
question.

 

Not true as a general statement. I have personally owned cars that were
specifically designed to only adjust the brakes when stopping in reverse
(anything GM from the 60s & 70s), and I have personally owned cars that only
moved the adjuster when the parking brake was set. I have also owned cars
with rear drum brakes that maintain adjustment in normal usage ('02
Pathfinder). Some don't even have an adjusting wheel, they use a sliding
wedge. Calling it all rubbish is rubbish. You have to look at the
mechanism used by the specific manufacturer to correctly answer this
question.

 

fair enough, but can i please be forgiven for responding to a civic
question on a honda forum? parking/reversing adjustment for a civic
/is/ rubbish...

 

fair enough, but can i please be forgiven for responding to a civic
question on a honda forum? parking/reversing adjustment for a civic
/is/ rubbish...

 

I'll buy that.

 

I'll buy that.

 

I'm not sure exactly what you mean about "generic advice." The UK sites manuals
at
http://www.honda.co.uk/owner/workshopmanuals2.html are presumably identical to
Helm. These days I have been checking both the UK site (= Helm) and Chilton's.
Sometimes the Chilton's manual is more specific and accurate; sometimes the UK
site is. Sometimes the wording is identical in both. For example, in another
thread recently I noted that the UK site manual had the exact same words as
Chilton's and Autozone's for a description of the ECU (under PGM-FI operation).

I get the feeling that Chilton's somehow legally draws from the manufacturer's
service manuals to the same extent as Helm. Autozone states somewhere at its
site that it has licensing agreements with Haynes and Chilton, so the frequent
Chilton-identical wording at it is no surprise.

But on the subject of brake adjustments, from what I can tell, there do appear
to be significant differences between Chilton's/Autozone and Helm/UK site.

So I note for the archive that, from what I could see, none of the manuals at
the UK site indicate a procedure for adjusting the rear drum brakes like the one
in Chilton's and at Autozone. I gather you too searched Helm and found only the
point you cite above on this subject. Likewise, the UK site manual for 1995-1997
Civics states "Depress the brake pedal several times to set the self-adjusting
brake" as one of its final steps in re-assembling the brake shoes.

I'm more inclined to believe Chilton's and Autozone reflect reality better on
this point. Namely, the adjuster gets crudded up pretty easily, so one has to
get in there and make the adjustment by hand. Jim and you both seem to agree
that this makes the self-adjustment feature somewhat suspect. Or the manuals
should maybe emphasize more, "Ya gotta clean the mechanism up every so often."
Guess one could and should read that into the Helm manuals. Maybe
Chilton's/Autozone's instructions go a bit more toward this.

In addition, I do have to wonder why there is this plugged port on many cars
(and certainly 1991 Civics) that by design is dedicated to manually adjusting
the star wheel adjuster. As I suggested before, manual adjustment is for
"non-normal wear"? But that doesn't really make sense. The shoes should wear
gradually. I see no reason why, barring the decrepitness of aged parts,
including a loss of spring in the adjuster "lever," the self-adjuster shouldn't
work fine.

I am a little tempted to go back into my rear drum brakes and disassemble enough
so I can thoroughly PB blaster the adjuster and where it mates with the clevis
pins, then maybe anti-seize these. Maybe replace the lever mechanism, if
possible.

I continue to appreciate the improvement in how the brake pedal feels but also
remain a bit concerned that a perhaps "too tightly adjusted shoe" is fooling me
into thinking I don't have to bleed more air. Then too there is such a thing as
psychological "overconcern" and perfectionist thinking...

More experience, and as always continuing to read here, over time will tell me
more, I reckon.

snip

Is this just a rough feel kind of test, based on experience? If not, your
elaboration is welcome.

snip

Ohmylord. Naturally all the travails of folks here with the much lower torqued
crank pulley bolts come to mind. I guess it's easier to figure a way to hold the
Beetle wheel hub steady than the Honda pulley, though, when applying the 250
ft-lbs of torque.