98 GS 300 Brake Master Cylinder - ClubLexus - Lexus Enthusiast Forums


98 GS 300 Brake Master Cylinder

Reply
 
 
 
Thread Tools Search this Thread
Old 04-02-14, 06:29 PM   #1
Aerostar
Driver School Candidate
Thread Starter
 
Join Date: Feb 2011
Location: MO
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Default 98 GS 300 Brake Master Cylinder

Hi Guys,

Just did the timing belt job. The Schley tool made the job SO much easier! Got the O-ring kit from Jeff Tsai for the VVTi cam gear and now with new NGK iridium plugs and a new set of plug wires everything is just amazing.

NOW I've got the Brake Master Cylinder re-pressurizing too often and its kind of loud so after searching the forums I ordered a new BMC unit- only it does NOT have the little electric motor on the bottom and the "soup can shaped" accumulator (I think that's what its called.)

I was wondering if anybody had any experience with scavenging the old "bottom half" and installing it on a new master cylinder?? I'm hoping I can do it because if not I may have to buy a complete new/used unit. Do I need any o-rings, etc? Anybody have a manual??

Many thanks for any help.

Rich
Attached Thumbnails
98 GS 300 Brake Master Cylinder-98-gs-bmc.jpg  
Aerostar is offline   Reply With Quote
Old 04-06-14, 06:39 PM   #2
Aerostar
Driver School Candidate
Thread Starter
 
Join Date: Feb 2011
Location: MO
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Default BMC replacement

Well,

I changed it out. Got everything to hook up. Now I just need to bleed the system out and flush the brake lines and bleed them too. I'll look around for a DIY brake bleed for the 98 GS300.

Lucky it was the new style. Had to go to a buddy's house and switch the sensor because it takes such a deep well socket.

Whew!
Aerostar is offline   Reply With Quote
Old 04-06-14, 06:56 PM   #3
rgarjr
Lexus Champion
iTrader: (1)
 
rgarjr's Avatar
 
Join Date: Feb 2004
Location: Southern California
Posts: 1,934
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Cool, where did u get that master cylinder? These things are very problematic on the 98-00.
rgarjr is offline   Reply With Quote
Old 04-07-14, 04:49 PM   #4
Aerostar
Driver School Candidate
Thread Starter
 
Join Date: Feb 2011
Location: MO
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Default 98 Master Cylinder

I got it on E-bay. I got got the brakes bled today with the help of my lovely Mrs. BUT I still get the "chirping" . Brakes are not soft and stop well but I get the chirping near the end of the charge cycle. Think I need to change the charging can and the motor too? Or is there a way to bleed it better to make sure that's not the problem. Possibly bench bleed before re-installing. I hate to have to take it off again.

Thanks.
Aerostar is offline   Reply With Quote
Old 04-07-14, 05:35 PM   #5
rgarjr
Lexus Champion
iTrader: (1)
 
rgarjr's Avatar
 
Join Date: Feb 2004
Location: Southern California
Posts: 1,934
Thanks: 0
Thanked 0 Times in 0 Posts
Default

I have had that annoying chirping sound on 2 master cylinder/abs pumps, both of them on 98-00 models. I think the chirping is caused by the motor, I mean what else can make that sound. Don't think the ABS modulator (actuator valves) are making it.

Bench Bleed, I guess you can fill it up with brake fluid and don't hook up the lines and pump it a bit.

Last edited by rgarjr; 04-07-14 at 05:41 PM.
rgarjr is offline   Reply With Quote
Old 04-07-14, 11:24 PM   #6
Aerostar
Driver School Candidate
Thread Starter
 
Join Date: Feb 2011
Location: MO
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Default

I tried bleeding it at the bmc connectors but still the "chirping".

Broke down and ordered the $1100 booster motor/accumulator assembly- OUCH.

Motor seemed to run and pressurize but would Chirp at the end of the pressurization.

Will take it all back out, install the motor and accumulator and put it back on.

Hope it works!
Aerostar is offline   Reply With Quote
Old 04-09-14, 09:06 AM   #7
rico23
Driver School Candidate
 
Join Date: Jan 2013
Location: NY
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Damn that hurts .. Have a sound coming from right behind my firewall soon as I turn on engine and sometimes when I break is that same sound you were hearing ? Have 01 with 90k on it changing out my rotors and pads in week or 2
rico23 is offline   Reply With Quote
Old 10-10-14, 11:23 AM   #8
Alphaman19
Pole Position
 
Join Date: Feb 2012
Location: NJ
Posts: 237
Thanks: 0
Thanked 2 Times in 2 Posts
Default

@AeroStar - I'm getting that chirping sound also (really embarrassing when someone else is in the car) .

Question: Did you have any issues putting the new pump/accumulator onto the new bmc unit?
I see that there's a red plastic sleeve/cover on the fluid line connecting the pumpaccumulator to the the bmc unit.
I think I can disconnect it w/o issue but wanted to see if you had any issues.
Alphaman19 is offline   Reply With Quote
Old 11-04-14, 08:25 AM   #9
RyanV
Lexus Test Driver
iTrader: (9)
 
RyanV's Avatar
 
Join Date: Jan 2008
Location: Texas
Posts: 1,304
Thanked 0 Times in 0 Posts
Default

Did you install a 01+ brake master?

I've got the chirp too on my 99' Gs400. Brakes work fine though, does the chirping indicate an actual problem?

It just sounds like it's coming from under the dash when I tap the brakes sometimes. I can be in park and tap the brakes and after I release the pedal I'll hear this audible screech chirp under the dash.

I do have an opportunity to buy a complete 2001 brake master unit today for $200. I want to make sure I can actually install that unit on my 99 Gs400. I keep reading about a sensor that needs swapped out, but I can't find the thread detailing that info.

Thanks,
Ryan
RyanV is offline   Reply With Quote
Old 11-04-14, 11:36 AM   #10
Alphaman19
Pole Position
 
Join Date: Feb 2012
Location: NJ
Posts: 237
Thanks: 0
Thanked 2 Times in 2 Posts
Default

Any 98-2005 bmc from any GS/SC will work.
As for the pressure(?) sensor, you actually have to disconnect it before you take the old unit out.
I'm not sure what year the configuration of the switch changed, but just compare your current one and the new one. If they're different, just unscrew you old one and put it in the new one. You'll see what I mean.
It's the kinda thing where a picture is worth a thousand words
Alphaman19 is offline   Reply With Quote
The Following User Says Thank You to Alphaman19 For This Useful Post:
Kingme600 (01-27-17)
Old 11-04-14, 02:22 PM   #11
RyanV
Lexus Test Driver
iTrader: (9)
 
RyanV's Avatar
 
Join Date: Jan 2008
Location: Texas
Posts: 1,304
Thanked 0 Times in 0 Posts
Default

Yeah no kidding. One guy made it sound like you have to take the entire brake master assembly apart before you can get a wrench around it. I just want to confirm because I'd rather not have to disassemble the entire unit.
RyanV is offline   Reply With Quote
Old 11-05-14, 05:55 AM   #12
RyanV
Lexus Test Driver
iTrader: (9)
 
RyanV's Avatar
 
Join Date: Jan 2008
Location: Texas
Posts: 1,304
Thanked 0 Times in 0 Posts
Default

Nevermind, looks like a large socket will easily pull that front facing sensor.
RyanV is offline   Reply With Quote
Old 01-27-17, 11:02 PM   #13
Kingme600
Driver School Candidate
 
Join Date: Jan 2017
Location: Ca
Posts: 4
Thanked 0 Times in 0 Posts
Default Master brake cylinder helpp

I just replace my masters brake cylinder on my 98 Lexus gs300 bleed it and all drived fine but brakes were very stiff..I drove the next day stop at a light and let go of brakes it didn't move had to gas it and rpm @3 while going under 25 on my way home I smelled smoked .. check my tires my rotors was all hot help me out always one thing after another thanks
Kingme600 is offline   Reply With Quote
Old 01-28-17, 06:28 AM   #14
Alphaman19
Pole Position
 
Join Date: Feb 2012
Location: NJ
Posts: 237
Thanks: 0
Thanked 2 Times in 2 Posts
Default

Quote:
Originally Posted by Kingme600 View Post
I just replace my masters brake cylinder on my 98 Lexus gs300 bleed it and all drived fine but brakes were very stiff..I drove the next day stop at a light and let go of brakes it didn't move had to gas it and rpm @3 while going under 25 on my way home I smelled smoked .. check my tires my rotors was all hot help me out always one thing after another thanks
Check you caliper slide pins. They're products gummed up and not allowing the caliper to "float" to and fro when applying or releasing the brakes.
Alphaman19 is offline   Reply With Quote
The Following User Says Thank You to Alphaman19 For This Useful Post:
Kingme600 (01-30-17)
Old 01-30-17, 09:27 PM   #15
Kingme600
Driver School Candidate
 
Join Date: Jan 2017
Location: Ca
Posts: 4
Thanked 0 Times in 0 Posts
Default

Quote:
Originally Posted by Alphaman19 View Post
Check you caliper slide pins. They're products gummed up and not allowing the caliper to "float" to and fro when applying or releasing the brakes.
Thanks I'll pull it out on my next day off .. somone else also said can be brake liner idk yet once I check it out I'll let u know
Kingme600 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Fuel Injector Seals sparkyguy Performance & Maintenance 0 03-24-17 04:48 PM
Broke your ABS/VSC sensor? Here's how to fix it! JeffTsai GS - 2nd Gen (1998-2005) 76 03-15-17 08:36 AM
TX 1995 Lexus sc300 2jzgte vvti swap Felts Lexus Vehicles Classifieds 5 09-23-15 02:54 PM
TX 2002 Black GS300 SPORT DESIGN-- Reduced for Quick sale by 4th of july weekend. B4TM4N Lexus Vehicles Classifieds 5 05-15-15 01:09 AM
2JZ water pump question hoosier58 Performance & Maintenance 1 09-26-13 04:56 PM


Tags
300, brake, gs, master

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not 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 Off
Pingbacks are Off
Refbacks are Off

Forum Jump


All times are GMT -7. The time now is 01:41 AM.


Copyright © 2000-2017 Internet Brands, Inc. All Rights Reserved
 
  • Ask a Question
    Get answers from community experts
What's your question?
Send