 Brake Bleeding Question |
|
|
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
|
| orbit398 |
 Feb 17 2016, 02:47 PM
Post
#1
|
|
Member  Group: Members Posts: 139 Joined: 29-April 15 From: League city, Texas Member No.: 18,681 Region Association: Southwest Region  |
I just install a 19mm brake master cylinder on the car I am restoring. I couldn't bench bleed the master cylinder like normal American cars. Is there any tricks to bleeding the system? I plan to bleed them tonight and will have a helper pumping the brakes. I just hope it's not an issue and we spend lots of time pushing air around.
Just wondering. |
   |
 
|
  |
Replies
| era vulgaris |
Feb 17 2016, 02:59 PM
Post
#2
|
|
J is for Genius Group: Members Posts: 982 Joined: 10-November 13 From: Raleigh, NC Member No.: 16,629 Region Association: South East States |
"normal American" (IMG:style_emoticons/default/confused24.gif)
I've never owned an American car so I wouldn't know to what you're referring! I put a 19mm MC on my old 914 and didn't bench bleed it. Start bleeding at the caliper that's furthest from the MC, and then work your way to the closest one. Your helper will start to feel the pedal firm up. I normally go through a couple times, and then go for a test drive. If it doesn't feel soft and I can lock the brakes up, it's good enough for me. I'm sure some others can chime in about the proportioning valve in the rear. I didn't have any problems, so I didn't mess with it. |
|
|
|
| orbit398 |
Feb 17 2016, 03:27 PM
Post
#3
|
|
Member Group: Members Posts: 139 Joined: 29-April 15 From: League city, Texas Member No.: 18,681 Region Association: Southwest Region |
QUOTE(era vulgaris @ Feb 17 2016, 02:59 PM)  "normal American" (IMG:style_emoticons/default/confused24.gif) I've never owned an American car so I wouldn't know to what you're referring! I put a 19mm MC on my old 914 and didn't bench bleed it. Start bleeding at the caliper that's furthest from the MC, and then work your way to the closest one. Your helper will start to feel the pedal firm up. I normally go through a couple times, and then go for a test drive. If it doesn't feel soft and I can lock the brakes up, it's good enough for me. I'm sure some others can chime in about the proportioning valve in the rear. I didn't have any problems, so I didn't mess with it. Thanks - I'll just do it normally with a helper. Assume it will be fine. Was just checking |
|
|
|
| Kansas 914 |
Feb 17 2016, 04:11 PM
Post
#4
|
|
Advanced Member Group: Members Posts: 2,999 Joined: 1-March 03 From: Durango, Colorado Member No.: 373 Region Association: Rocky Mountains 
|
Did you happen to install a URO 19mm master cylinder? You may or may not get a good pedal. Some folks on 914World have discussed this.
|
|
|
|
| screenguy914 |
Feb 17 2016, 04:42 PM
Post
#5
|
|
Member Group: Members Posts: 249 Joined: 6-July 09 From: So. Cal Member No.: 10,540 Region Association: Southern California |
QUOTE(Kansas 914 @ Feb 17 2016, 02:11 PM) Did you happen to install a URO 19mm master cylinder? You may or may not get a good pedal. Some folks on 914World have discussed this. If you attempt to bleed the system using an existing master cylinder, place a block of wood under the brake pedal to limit MC piston travel. This prevents over stroke which allows cylinder deposits to damage the hydraulic seals. This results in internal fluid leaks and an inability to properly pressurize the system to push fluid and air bubbles out of the system. Disk brake systems don't use a MC check valve. When bleeding, this allows brake fluid to simply flow out of the bleeder screws under gravity. This procedure allows air to escape from the brake line. Repeat for each caliper. Doesn't waste expensive fluid either (talk to those who use a pressure bleeder tank).   Sherwood |
|
|
|
| Kansas 914 |
Feb 17 2016, 05:14 PM
Post
#6
|
|
Advanced Member Group: Members Posts: 2,999 Joined: 1-March 03 From: Durango, Colorado Member No.: 373 Region Association: Rocky Mountains
|
QUOTE(screenguy914 @ Feb 17 2016, 03:42 PM) If you attempt to bleed the system using an existing master cylinder, place a block of wood under the brake pedal to limit MC piston travel. This prevents over stroke which allows cylinder deposits to damage the hydraulic seals. This results in internal fluid leaks and an inability to properly pressurize the system to push fluid and air bubbles out of the system. Disk brake systems don't use a MC check valve. When bleeding, this allows brake fluid to simply flow out of the bleeder screws under gravity. This procedure allows air to escape from the brake line. Repeat for each caliper. Doesn't waste expensive fluid either (talk to those who use a pressure bleeder tank). Sherwood All good advice! |
|
|
|
Posts in this topic
orbit398 Brake Bleeding Question Feb 17 2016, 02:47 PM
billh1963 914 Brake Bleeding
After talking to many owners,... Feb 17 2016, 02:55 PM
Bartlett 914 I like to bleed the brakes as shown in your pictur... Feb 18 2016, 12:11 PM stugray Excellent advice above, but I will add some more.
... Feb 17 2016, 05:32 PM motorvated I recently installed a new 19 mm master cylinder, ... Feb 17 2016, 06:20 PM |
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 8th June 2024 - 12:19 PM |
Invision Power Board
v9.1.4 © 2024 IPS, Inc.