Larry, Jay, Steve, Dick, Jim, et Listers,
I'm happy to see so much interest in brakes. When I last logged on, I just
had time to poke a little fun at Jay's expense (I'm glad to see he got it)
It does show one of the great powers of the Internet that we can exchange
pages from manuals and all sorts of fun stuff that's even, at times,
enlightening if not entertaining.
Other than my hyperbole about chasing a Cobra, my post was just taken from
the two versions of the Rootes Manual, and on which I take no particular
sides being merely curious as to the facts. I have long since forgotten
just where and why I adopted the bleeding order I have used. It obviously
wasn't from the Rootes Manual, a fact of which, thanks to the List, I am
now well apprised. But, hyperbole aside, it's hard to imagine anything more
important that the optimal functioning of our Tiger's brakes, so the least
we can do is invest some small percentage of our efforts (and money)
relative to what we invest in our motors to getting them up to near optimal
performance. It's obvious that you guys feel the same way too, so no sense
preaching any further to the choir.
Regarding removing the brake fluid every year, I've never actually done
this myself, except as part of an overhaul, and, as I mentioned before, I'm
not sure how to get all the fluid out. I guess fully collapsing all the
slave cylinders, filling and collapsing again, repeat until satisfied is
the only procedure I can suggest. Unless, like your calipers Larry, there
are bleed screws top AND bottom (now I see the utility of this).
Like most everything, especially automotive things, you can always find
opposing expert opinions. I just did a search of the Web and came up with
several "expert" reports on this subject.
The first one says on single master cylinder cars, start nearest the master
cylinder and work progressively toward the farthest. On newer cars with
diagonal safety systems, the sequence should start with the wheel closest
to the master cylinder as before, however the next wheel in the sequence
will be diagonally aligned with that wheel. For example left-front,
right-rear, right-front, left-rear. The URL for this reference is:
http://www.weekendmechanicsclub.com/Features/Feature-Mityvac.htm
The second in order on the search list shows a nifty product, but has no
obvious instructions as to order:
http://www.ipdusa.com/Volvo/catalog/brake_bleeder.htm
Third on list, another interesting set of tips, but nothing on order:
http://www.vtr.org/maintain/brake-bleeding.html
Next on the list, some more on bleeding order (presumably for diagonal
braking systems) The order is (sitting in the drivers seat) right rear,
left front, left rear, right front.
http://3si.org/bleedingbrakes.html
Next on list says start at the farthest and work toward the master
cylinder. "The easy way to remember the brake bleeding pattern is to start
from the cylinder furterest away and work back." Can we trust someone who
says 'furterest'??
http://www.scruz.net/~barneym/toy_root/techneek/brakbled.htm
Well, there's only 8,289 more on the list, but I think you're getting the
picture. We have two basic schools of thought going here: those that start
at the beginning and work towards the end, and those that start at the end
and work towards the beginning. So who's right? Which way do you install
your toilet paper rolls? A recent survey says that 2/3 of those surveyed
install them with the loose end away from the wall and 1/3 put them with
the loose end next to the wall. NOBODY puts them on randomly; it's just
human nature to create order in our lives I guess. Maybe it's the same with
bleeding the brakes.
At 08:13 PM 5/30/00 -0400, Larry Paulick wrote:
>Hi Bob. I have been reading the brake bleeding sequence as posted. The
>books on brakes, the one I have im my library is an HP Book on Brakes by
>Pogh, have always stated to bleed the farthest wheel and work toward the
>closest to the MC.
>
>Manuals from most US car manufacturers also state the same thing. So
>right or wrong, I have been going with the published works of the brake
>experts and US manufacturers.
>
>I designed a new brake system for my MKI, and when sorting it out the
>same advise was given by Wilwood, Baier (spelling), Coleman, Dave Bean
>Engineering, and others.
>
>Their comments were, "Like Of Course Duffus". But, I just asked anyway,
>to confirm what I though I had been reading was correct, according to
>someone else.
>
>I also did not understand why anyone would bleed all of the fluid out of
>the system and start from a brake system with only air. The old seals
>can be severely damaged by having to pump them through the complete
>travel, where they will encounter corrosion, dried brake fluid, etc.,
>that can damage the old seals, much less new ones.
>
>Of course, if it works for you, keep at it.
>
>The best system, that I have used, is a pressure bleed system, going by
>several names, but EZ Bleed (spelling again) is what I use on my other
>cars. It uses low pressure, 5-15 psi, and pressurizes the MC, then you
>just open the bleeder screw. After getting the car up in the air, and
>wheels off, it takes less than 10 minutes to do the bleeding. Pressure
>bleeding is recommended by several car manufacturers who use ABS to get
>the air and old fluid completely out of the system. System is cheap,
>and I think I paid around $35.
>
>Now if I can just find extra MC caps for the Datsun 310 tandem master
>cylinder, I will bleed the Tiger with this system.
>
>Of course there are the bleed screws that have a check valve, where you
>step on the brake, and bleed with this valve open, as the check valve
>stops air from coming into the system when you let off the pedal.
>
>Sounds great, does anyone have experience with this system. Summit has
>them at $10 a pair. I would need 10 bleeder screws to do my brakes, and
>one for the McCloud hydraulic throughout bearing, so I am waiting for
>someone's experience before speeding $60 for bleeder screws.
>
>Anyway, that's my thoughts, and experience. Regular brake bleeding by
>any method is a really good idea that is over looked by many, and well
>worth the discussion.
>
>Larry
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