If either of the rear brakes is locking up before the front, you might give
some thought to the brake proportioning valve. I can't say I've ever heard
of one giving a "soft pedal", but I suppose it's conceivable.
Good luck,
~alan
'71B
Reply to:
Alan Lott
GTA, Auburn Univeristy
Department of Rehabilitation and Special Education
My Office- (334) 844-2092
Department- (334) 844-5943
Fax- (334) 844-2080
-----Original Message-----
From: owner-mgs@autox.team.net [mailto:owner-mgs@autox.team.net] On Behalf
Of Florrie & Allen Bachelder
Sent: Friday, July 16, 1999 8:18 PM
To: mgs@autox.team.net
Subject:
Hi List -
' Sorry this is rather long, but I need some advice. Back in May I started
having problems with a soft low brake pedal on my '76 B. It's never been
firm like my non-servo Bs but it got quite a bit worse. A Roanoke Brit Car
Resto guy noted the engine idle was affected by the brake pedal and
suggested it was probably a vacuum leak in the servo. So I sent a servo
from my '76 parts car off to Apple Hydraulics and got it rebuilt.
While at it, I put in brand new master cylinders (clutch and brake) from
Moss and on advice of the same guy in Roanoke, flushed out the whole system
and converted to DOT 5. I did bench-bleed the MC first. Still got a soft
pedal and within three days my left front caliper was leaking (I've never
had a caliper leak in all my 15 years experience with MGBs).
' Was about to rebuild calipers (as I've done on other Bs) and discovered
Advance Auto has rebuilt calipers with OE pistons for $35.99 - with
lifetime warranty. So I flushed out the system - thoroughly - converting
back to Castrol GT/LMA DOT4 before installing rebuilt calipers. Again, I
bled the whole system thoroughly - starting with left rear, then right
rear, right front and finally left front. There's no DOT 5 left in the
system.
Still soft pedal. Pads are good. The brake hoses were replaced about two
years ago, as was the left rear wheel cylinder which I discovered leaking
at that time. Shoes looked good then. Car has gone about 15,000 miles
since.
The right rear wheel cylinder is the only item in the system that I haven't
replaced. It is working and although I haven't had the drum off, there is
no outside sign of leaking. I am aware that lots of DIYers put rear brake
shoes on wrong and mine are right - like in the Bentley illustrations. The
rears are set as high as I can get 'em without overheating the hubs - in
fact I had to back my left rear off a bit. Even when it was set too high,
soft pedal.
If I pump the brakes once, on the second application, they feel good. I
know this is a classic symptom of rears in need of setting up, but that's
not the problem. At its worst, the pedal may feel awful but the brakes do
work well - although the right rear tends to lock up first on hard stops.
I even turned the brake light switch in about 1/2-turn - which minimizes
the 1/8th-inch pedal freeplay and, not surprisingly, makes no difference.
The pedal does not "leak down" nor am I losing any brake fluid. In fact, I
swear the level in the reservoir went UP slightly after a 40-mile test
drive. Could there still be an air bubble in the system...? I suppose
although it seems unlikely. What could I be overlooking? Should I replace
rear brake shoes?
Many thanks!
Allen
******************************************
Allen H. Bachelder =iii=<
Sinking Creek Home for Wayward MGs
New Castle, VA 24127
USA
540/544-7333
******************************************
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