I did a brake flush yesterday, by myself for the second
time, on my 91 Civic LX (176k miles). I use the Mity-Vac
system ( a hand-held vacuum pump, connecting to a small
container to collect fluid, tubing, and adapters). It went
much more quickly. One concern I have is that, while the kit
has a well-fitting adapter for the front bleeder bolts, it
does not have a good one for the rears. The front setup
holds a vacuum really well as I bleed fluid. By contrast, on
the rears, massive air bubbling occurs, and I have to
continuously pump to maintain vacuum.
I think it's because the rear adapters fit so loosely that,
when I draw a vacuum with the pump, it sucks air in at the
I am thinking of buying a set of those one-way (that is,
check) bleeder valves that Pep Boys, for one, sells, to (1)
maybe get a better fit from adapter to valve; and (2)
minimize air introduction into the rear brake system.
Can anyone make other suggestions?
I want to stick with the Mity-Vac approach, as opposed to
getting a friend to push the brake pedal while I bleed at
each wheel. The Mity Vac system works really well on the
front. I am optimistic that some brainiac here can help me
getting the rears working better, or I'll stumble onto an
improvement for the rears.
A few comments for the archives:
-- I used a 32 oz ( = two pints) container of Valvoline
"exceeds DOT 3 and 4 requirements" brake fluid for the
flush. I had a second container ready, in case I found a lot
of dirt etc. in the fluid I bled. I did not. It seemed
pretty dirt free.
-- About 1.8 years and 22k miles have elapsed since the last
flush. The Owner's Manual recommended interval is 2 years
and 30k miles. I see a lot of folks here do a brake system
flush once a year. I was thinking of switching to a one-year
interval, but think I'll stick with two years using the more
expensive, supposedly more moisture resistant Valvoline
brake fluid. I live in a low humidity part of the country,
-- The brake pedal travel before and after the flush still
seems a little large. I'm thinking it's because in fact I am
not getting all the air out of the system, and if any part
is to blame, its the rear bleeder bolt/adapter set-up I'm
using. Or possibly it's the fact that yesterday just before
the flush I disassembled, cleaned, lubed, and inspected,
then re-installed the rear brake shoe assemblies, and so
they weren't quite seated right.
-- I do not see symptoms of a leaky master cylinder (e.g.
the brake pedal does not keep going down after I first hit
what seems "bottom").