On 3/17/2015 11:05 PM, firstname.lastname@example.org wrote:
Which is actually what started this:
On 3/16/2015 8:54 PM, Jim Wilkins wrote:> Next question:
> How do you seal the air leak along the bleeder threads when vacuum
> bleeding? I didn't want to squirt on something incompatible that might
> get back into the cylinder.
I've replaced brake lines and/or wheel cylinders on every vehicle I've
owned, since I keep them in good condition a long time. The thread
leakage had never been an issue for me until I had to diagnose and
cure a spongy pedal, and couldn't distinguish leakage at the bleeder
from air in the lines.
The advice I was hoping for was a recommendation of a compatible or
insoluble heavy grease to put on the bleeder threads. The only "brake
grease" I have is for the caliper slides and rear self-adjuster, and
its strength is a high temperature tolerance to keep it off the
friction surfaces rather than compatibility with the fluid and rubber
On Wednesday, March 18, 2015 at 5:20:09 AM UTC-7, Bob Engelhardt wrote:
I've used HandiTak for that (and have heard that plumber's teflon tape
also works, but cannot confirm).
<(Amazon.com product link shortened)>
It deteriorates incontact with brake fluid (I was sloppy), but it seals well enough to
do a vacuum bleed.
For me it means connecting a Mityvac or HF bleeding kit to the wheel
cylinder bleeder, pumping to 25", opening the bleeder and watching the
fluid and maybe air flow out. Normally I stop when the fluid turns
lighter, then torque the bleeder to spec, blow out the remaining
water-absorbing fluid, replace the rubber cap and top off the master
Now that I'm retired and not driving 50 miles in stop-and-go freeway
traffic every day the fluid doesn't heat up enough to darken.
And there is NO WAY air or anything else is going to get in to the
system due to leakage around the bleeder screw threads doing it that
way. What's the big issue about the threads not sealing 100%???
When the screw is closed the threads don't have to seal anything
because the tapered seat does the sealing..
Right. As I said, the problem appeared only when I was trying to
refill a spliced line and I couldn't tell if the bubbles meant I
needed to keep flushing my limited supply of genuine Honda brake fluid
through. That's when I woke up the neighbor and asked for help pushing
the pedal, which blew out the residual air in a different line that
was making the pedal very soft.
Today I asked about bleeding at the dealership while stocking up on
more fluid. They always have someone to pump the pedal. They also gave
me a trade-in value. At least the 15-year-old car is worth something
to me. Maybe I scared it into behaving for a while.
On Thursday, March 19, 2015 at 4:27:20 PM UTC-7, Clare wrote:
>> Describe what you call a vacuum bleed please - there are so many
The two-person bleed procedure pressurizes the brake lines and blows crud out of
them. A one-person vacuum bleed is also possible, using atmospheric pressure
at the master cylinder and pulling a vacuum at the bleed port with a "Mityvac" brand
hand pump. The problem there, is that the (loose) bleed valve can fill the little
waste bottle with brake fluid from the lines, or with air from the lines, or with
air that leaks past the threads of the valve. Even if air doesn't get into
the brake lines, there's no way to know when the bleed is good enough,
unless you smear some sealant around the valve threads.
I've never seen a professional mechanic put sealer on a bleeder
thread.. I've never put sealer on a bleader screw.. I have a little
battery operated electric vacuum bleeder. I have a mighti-vac. I
virtually never use them for bleeding brakes. So much easier to
gravity/pump bleed. The pressure bleeder was the cat's meow back when
I was at the dealership. Clamp the fitting on the master, dial up the
pressure on the tank, open the bleeder 'till the bubbles stop, Close
the screw. repeat on the other 3 lines.
It wasn't foolproof. Couldn't pressure bleed a '60's Vauxhaul with
twin leading shoe brakes while sitting level. Reverse bleeding is the
"secret weapon" in cases like that. Standing the car on it's nose
overnight works too. Don't want to have to do that too often!!. (line
went into the "top" cyl. with a jumper line from the top cyl to the
bottom cyl, and the bleeder on the bottom of the bottom cyl, of all
I would and have used "SIL-GLYDE Lubricating Compound" for stuff
like that. Been using it to protect/seal the reservoir/pumps area on my
Magna motorcycle for many years now. The tube I have is very old, given
to me by a professional mechanic. He was giving me advice on how to
rebuild the front disc brakes on my truck. See:
(Amazon.com product link shortened)
Haven't noticed any thing odd/weird going on when I change the fluid in
the reservoirs on the cycle yearly.
Yep, that's the right direction. Thanks.
Here is some discussion for and against using it on disk brake piston
They make/sell it with several different names. I don't know if it is
all the same or not. That article doesn't really say which version the
original poster was using but I got the feeling it was the stuff for
stopping squeals. Lots of other useful suggestions there though. For
some info on the different "Glydes" see:
They seem to like that "Glyde" name :)
These are somewhat helpful:
My shop manual is similar. The text says to "Coat the piston, piston
seals and caliper bore with clean brake fluid", but doesn't mention
the piston seal grease.
I suspect that a grease meant to go on the piston seals won't cause a
problem if a bit of it leaks in from the bleeder screw, although they
must have a reason for specifying a different grease on external
On Tue, 17 Mar 2015 23:05:53 -0400, email@example.com wrote:
Most of which have disc brakes. That cuts way down on the mess left
from a leak.
It's messy, and fluid can leak into the brake area beneath the
cylinder on older cars and trucks. Not much (more of a seepage) and
not on the shoes, but some. I prefer a cleaner job.
The low pressure used would make it seem less troublesome.
I have 53k miles on my '07 Tundra now, and need to check/replace pads.
Do you have any specific suggestions or tips toward brake jobs for
them? You've been in the loop considerably more recently than I.
There is zero pedal undulation, so I doubt I need to turn the rotors,
unless that's a recommended procedure. I haven't yet looked into it.
I know the brakes have been wearing because I've needed to adjust the
emergency brake cable twice now. (step on/step off style) It's a
4-wheel disc setup, which I adore. It was the brake system alone which
killed my enthusiasm for the Tacoma and sold me on the Tundra. The
Tacoma took both feet and all I had to make it stand on its nose, and
it still wouldn't. The Tundra danced to a stop quickly and easily,
with little pedal pressure, nearly ripping up the macadam in the
Always bear in mind that your own resolution to
succeed is more important than any one thing.
Only thing I have done was to pull the bleeder and dab some silicone
grease on the threads. I suppose you could crack the bleeder and coat
the thread area with common RTV or even silly putty. It would stop the
leak around the threads, but if you have drum brakes you might still get
leaks past the cups.
I use a pressure bleeder for the vehicles that won't reliably gravity bleed.
I don't vacuum bleed mine. I get someone to help me. When working in
the trade, that's what apprentices were for - I'd pump the pedal and
HE would get sprayed!!!.
I've actually found that single handedly I can usually bleed most
brakes pretty well by JUST cracking the bleader and forcing the last
air out past the threads.Releasing the pedal slowly doesn'r draw in
enough air to cause a problem. Disk brakes bleed themselves.
I can ask the retired neighbors who call on me when their stuff
breaks, IF they aren't asleep or away at the VA.
In the past a pipe or broomstick resting on the brake pedal and
pulling against the steering wheel with bungee cords has been enough
to pump the old discolored fluid out of the wheel cylinders. Vacuum
bleeding does that pretty well too, when I know that the pedal is
solid and the bubbles I see in the tube are only from the air leak at
In this case the long line to the rear had mostly drained so I used
vacuum to refill it quickly.
On Mon, 16 Mar 2015 19:23:11 -0400, firstname.lastname@example.org wrote:
Newp. Iffen you didn't buy them from the dealer, you bought a used
car. Like gravity, it's the LAW!
Well, if you're not smarter than the cheap Chiwanese part, then... ;)
I had a fun half hour this morning. Y'know that new battery I bought
a couple weeks ago? The old one decided it would die on me this
morning on the way to a job. I lucked out, listening to my intuition
those weeks ago, so I was back on the road in 20-some odd minutes.
However beautiful the strategy, you should occasionally look at the results.
-- Sir Winston Churchill
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.