Dave and James -
>When
disconnecting booster vacuum from the intake and plugging it, the problem
wasn’t there. The rebuilder advised it shouldn’t be the booster and let
it break in a little.
I don't know who your rebuilder is, but I would
advise finding someone that knows what they are doing. Boosters don't need to
'break in a little'. They are not like a new pair of shoes or jeans. LOL.
Either they work or they don't.
If you are not inclined to rebuild the booster
yourself, then I would recommend Booster Dewey, who has now been joined by two
other rebuilders and changed their name. Here is their website: https://www.powerbrakebooster.com/
I assume that the quality is still the same. But YMMV.
Ron
James,
Danny has good points. It could very well be your master, or
booster. I will say we had this problem recently on our K, after
installing a new dual reservoir master with a rebuilt booster.
When disconnecting booster vacuum from the intake and plugging it, the problem
wasn’t there. The rebuilder advised it shouldn’t be the booster and let
it break in a little.
Turned out the booster had been damaged by UPS in shipping, had gone back
to the rebuilder (due to the box being trashed), they checked it and then
resent it to us. When we installed it we had the sluggish pedal rebound
I mentioned (could lift pedal from underneath with foot, or it would come back
on its own after a second or two but brakes were engaged until pedal was back
up). After a few miles of seeing if it would break in, it did get a
little better, but then while trying to drive to the club mini meet the brakes
became suddenly jammed (pedal would not depress). Used the parking
brake to stop, disconnected the booster vacuum and plugged it, turned around
and drove back home fine on manual brakes.
Sent the booster back to the rebuilder and installed the old booster the
K came with in the meantime. Problem went away. (Why did I switch
out the booster in the first place? We we were changing over to Dot5 and
the old booster already had peeling paint from Dot 3 leaking on it).
So in our case, the booster not only was causing insufficient pedal
rebound, but also jammed the brakes after not many miles. And all that
while thinking the booster was rebuilt so should be good. I say this
because you might consider disconnecting your booster and trying manual brakes
until you can rule in or out whether the booster is safe.
V/r
D&K
Sent from my iPhone
On Jan 22, 2023, at 1:33 PM, dplotkin
<dplotkin@xxxxxxxxxxxxxxxxxxx> wrote:
James, I once experienced a similar failure on my 60 Buick. Pedal went
to the floor seemingly held by vacuum. Pedal came up with engine off.
Is your pedal returning with no vacuum, when engine is off,?
Most master cylinders have a spring inside to bring it back. I see this
external spring and bracket stuff when boosters or cylinders are wrong or
poorly repaired. I see lots of Treadlevacs that way.
Say whether the pedal is held by vacuum or gravity.
Dab
Sent from my Verizon, Samsung
Galaxy smartphone
-------- Original message --------
From: 'James Douglas' via Chrysler 300 Club International
<chrysler-300-club-international@xxxxxxxxxxxxxxxx>
Date: 1/22/23 1:12 PM (GMT-05:00)
To: "Chrysler 300 List Server
(chrysler-300-club-international@xxxxxxxxxxxxxxxx)"
<chrysler-300-club-international@xxxxxxxxxxxxxxxx>
Subject: {Chrysler 300} 300K Midland Booster
I just went to pull the 300K off the rack, I have the steering all back
in with the temp box. I went to back up and the brakes were locked.
The pedal did not return. Now I had the booster off. It looked
like it had been rebuilt at some time in the last 20 years. There was some
surface rust on the can and also some on the plunger. I took the can apart,
just the two shells and I cleaned everything on a wire wheel and gave the
parts some zinc paint. Nothing on the inside. I put it back together and
that was it. I reinstalled it after the steering was in.
Now one thing that has not worked well is the brakes since I
picked it up. I do plan on an entire rebuild, but that is after the
steering. There was a funky return spring and bracket on the brake
pedal arm that I took off. It did not seem to affect anything. But now I see
why.
Anyone have any ideas? The service manual does not have
anything on pressing the pedal down and and it staying there. I can pull it
back with my foot.
I doubt it is the MC but anything is possible.
Help!
--
For archives go to
http://www.forwardlook.net/300-archive/search.htm#querylang---
You received this message because you are subscribed to the Google
Groups "Chrysler 300 Club International" group.
To unsubscribe from this
group and stop receiving emails from it, send an email to
chrysler-300-club-international+unsubscribe@xxxxxxxxxxxxxxxx.
To
view this discussion on the web visit
https://groups.google.com/d/msgid/chrysler-300-club-international/CY5PR19MB617125ECCB9B7E689CB54F4093CB9%40CY5PR19MB6171.namprd19.prod.outlook.com.
--
For archives go to
http://www.forwardlook.net/300-archive/search.htm#querylang---
You received this message because you are subscribed to the Google
Groups "Chrysler 300 Club International" group.
To unsubscribe from this
group and stop receiving emails from it, send an email to
chrysler-300-club-international+unsubscribe@xxxxxxxxxxxxxxxx.
To
view this discussion on the web visit
https://groups.google.com/d/msgid/chrysler-300-club-international/63cd816a.050a0220.6540e.d4cfSMTPIN_ADDED_MISSING%40gmr-mx.google.com.
--
For archives go to
http://www.forwardlook.net/300-archive/search.htm#querylang---
You received this message because you are subscribed to the Google Groups
"Chrysler 300 Club International" group.
To unsubscribe from this group and
stop receiving emails from it, send an email to
chrysler-300-club-international+unsubscribe@xxxxxxxxxxxxxxxx.
To
view this discussion on the web visit
https://groups.google.com/d/msgid/chrysler-300-club-international/D39865C3-7B08-44A4-88CB-9D23BDF9B6EC%40gmail.com.
--
For archives go to
http://www.forwardlook.net/300-archive/search.htm#querylang---
You received this message because you are subscribed to the Google Groups
"Chrysler 300 Club International" group.
To unsubscribe from this group and
stop receiving emails from it, send an email to
chrysler-300-club-international+unsubscribe@xxxxxxxxxxxxxxxx.
To
view this discussion on the web visit
https://groups.google.com/d/msgid/chrysler-300-club-international/49D2C44BF89E4B48AA5AD266917B1EC6%40ThinkPadL520.