30 coupe losing brake pressure - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum

Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Suspension - Brakes - Steering
User Name
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 08-11-2012, 04:27 PM
Registered User
Join Date: Oct 2005
Location: las vegas, nevada
Posts: 182
Wiki Edits: 0

Thanks: 1
Thanked 5 Times in 3 Posts
30 coupe losing brake pressure

Hi, need a little advise please. I have a 30 model A coupe 350/350 and disc fronts and drums rear. The system is fairly new, I ran my own steel lines and got a corvette cylinder from So-Cal. Im not running a booster and plumbed the two residual valves in with a wildwood proportioning valve. I bled the brakes and had good pedal and can see no leaks. It sat in my garage for a week and when I got in the pedal went to the floor. If I pump them, the pedal comes up but Im losing pressure somewhere. I had the cylinder for a year before installation and sat there dry for another six months before I pulled it and primed it. Kids could have pumped them playing in the car so Im wondering if it could be the master? Like I said everything looks dry at all conections so Im confused. Could be me cuz I aint getting any younger. anything you can come up with I'll check. Bill

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 08-11-2012, 05:34 PM
Cape Cod Bob's Avatar
Registered User
Last wiki edit: How to title a hot rod Last photo:
Join Date: Jul 2007
Location: MA
Posts: 1,293
Wiki Edits: 1

Thanks: 41
Thanked 54 Times in 43 Posts
Bill, I have had a similar ongoing problem in my sedan. So have several others on this forum if you do a search.
First I will reccommend going to MP brakes site and order a catalog. They have a lot of info on there maybe able to access it on their site.
Start with being sure that no air is trapped in the calipers. The bleed screw should be at 12 o'clock to get all the air out. Also rebleed the MC.
If you are running a combination valve be sure it is centered so pressure to both front and rear.
I assume underfloor MC so residuals are in place.
I don't think pressing the pedal dry would cause to much problem, however replacing the O rings may be needed. The feel would be different though.
When you pump them up does it hold. If not it would be the MC.Or a leak.
Master Power Brakes - Troubleshooting
Reply With Quote Quick reply to this message

Recent Suspension - Brakes - Steering posts with photos

Quick Reply

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Holley blue losing pressure part II inbredjedd Engine 2 09-12-2011 02:25 PM
Losing Fuel Pressure frickenbored Engine 10 07-02-2011 10:46 AM
engine problem with losing oil pressure F250 Hotrodding Basics 1 04-04-2011 10:21 AM
losing fuel pressure Cobra720 Engine 4 10-30-2010 01:40 PM
losing fuel pressure tg40 Engine 6 02-25-2006 09:43 AM

All times are GMT -6. The time now is 03:40 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.