You can just put the Mityvac on the suction side of the booster, suck it
down and see if it holds vac. If it doesn't then the diaphragm is bad.
I replaced to MC on the TD, getting those line fittings back on the part
was a nasty unpleasant job. They are pretty tight anyway with the lines
being the way they are, and getting them lined up just right to get the
fittings started can either take 10sec or 30min. While brake fluid is
all over. Guess which they took...
--R
On 12/10/2010 5:48 PM, Max Dillon wrote:
Greg, tell me more about this test for the power assist unit. Have
Mity-vac!
-Max
-----Original Message-----
From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com]
On Behalf Of Greg Fiorentino
Sent: Friday, December 10, 2010 5:06 PM
To: 'Mercedes Discussion List'
Subject: Re: [MBZ] Symptom - sinking brake pedal
A failed vacuum pump can damage the power assist unit. This can be easily
tested with the Mity-Vac.
Greg
-----Original Message-----
From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com]
On Behalf Of Max Dillon
Sent: Friday, December 10, 2010 1:00 PM
To: 'Mercedes Discussion List'
Subject: [MBZ] Symptom - sinking brake pedal
OK folks, check my work here. After rebuilding the calipers on my '95 E300,
the service manual says to apply hard pressure to the brake pedal for a
short period of time, and then check for evidence of leaks. When I did this
test, no sign of any leakage, but the brake pedal slowly sank while I stood
on the pedal. I think the master cylinder is probably bad.
This car also has a very soft brake pedal feel compared to my '87 wagon;
feels a lot more like the '72 Buick I used to drive in high school. I've
bled the system with my pressure bleeder, and now it has new rotors and new
Akebono ceramic pads at all four corners. All this work did little to
improve the pedal feel (had Pagid pads on it when I got the car). The car
stops just fine, but the pedal is too soft in my opinion. This car was
driven by the PO with a failed vacuum pump, so maybe something was damaged
by too much driving with no vacuum assist?
Very respectfully,
/s/
Max Dillon
Charleston SC
'87 300TD 332k miles
'95 E300 277k miles
'73 Balboa 20
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_______________________________________
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To search list archives http://www.okiebenz.com/archive/
To Unsubscribe or change delivery options go to:
http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
_______________________________________
http://www.okiebenz.com
For new and used parts go to www.okiebenz.com
To search list archives http://www.okiebenz.com/archive/
To Unsubscribe or change delivery options go to:
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