Damaged Brake Booster
searcherrr
02-16-2007, 06:41 AM
Could someone look at these pics and tell me if you think I have a damaged brake booster? I'm thinking I do, but this is the 1st time I've ever had to deal with one before. Contributing to this thought I cannot adjust my brake pedal height to the proper spec level because I've got the adjustment bolts at their limits in the current config with the booster I think is broken. From what it appears like in the photo below it looks like my current brake booster is sunken in some and it makes a popping sound when I press it with the pedal. All other brake parts have been replaced so this booster, proportioning valve (doubt it), and the brake pedal itself (doubt it) are the only remaining untouched brake parts causing this popping sensation when I press the pedal all the way down as well as it seems I'm unable to use full braking power due to not being able to adjust the brake pedal to the right spec height.
Here's a pic of a good one:
http://www.thinkrolland.com/3000GT/images/ExternallyLinked/3000GT-BadBrakeBoosterCompare-0003.jpg
http://www.thinkrolland.com/3000GT/images/ExternallyLinked/brakepedalxv7.jpg
Here's a pic of the one I think is bad (damaged):
http://www.thinkrolland.com/3000GT/images/ExternallyLinked/3000GT-BadBrakeBoosterCompare-0005.JPGhttp://www.thinkrolland.com/3000GT/images/ExternallyLinked/3000GT-BadBrakeBoosterCompare-0005-smaller.jpg
Here's a pic of a good one:
http://www.thinkrolland.com/3000GT/images/ExternallyLinked/3000GT-BadBrakeBoosterCompare-0003.jpg
http://www.thinkrolland.com/3000GT/images/ExternallyLinked/brakepedalxv7.jpg
Here's a pic of the one I think is bad (damaged):
http://www.thinkrolland.com/3000GT/images/ExternallyLinked/3000GT-BadBrakeBoosterCompare-0005.JPGhttp://www.thinkrolland.com/3000GT/images/ExternallyLinked/3000GT-BadBrakeBoosterCompare-0005-smaller.jpg
Stealthee
02-16-2007, 08:51 AM
Have you beld the lines? I have never heard of anyone adjusting the brake height on a 3s. Also the booster looks normal. Thats how they are shaped.
searcherrr
02-16-2007, 04:12 PM
Have you beld the lines? I have never heard of anyone adjusting the brake height on a 3s. Also the booster looks normal. Thats how they are shaped.
Naa dude, you don't understand I've been waiting nearly 2 years to make her road worthy again and everything else is done. I even rebuilt the Master Cylinder and of course bled properly. It did what its doing before and after all the work I put in. If you look more closely at the pic of the old one it is sunken in around the rod and if i compare by "feeling" around (on the new one ) that accordian looking rubber gasket there is a solid steel cylinder around that rod that goes all the way up to that gray felt looking thing that you can see thru the circular holes of the accordian gasket you feel a solid object underneath. If I measure from the base of that accordian gasket to the top of it on the old and new the ole one is shorter by about 1 inch than the new one and that distance is the exact distance I have left to get my brake pedal into proper brake pedal height.
I'm not trying to disprove you or answer my own question, but I feel from your response you've not seen what I see. It is this sunken-in-ness on the old one that has me questioning and because whenever I press the brake pedal there is an internal popping sound coming from where the booster is under the hood whenever I push the pedal all the way down. So what you (or anyone else) think? I mean this can't be the first time these conditions have been found on an old brake booster.
Naa dude, you don't understand I've been waiting nearly 2 years to make her road worthy again and everything else is done. I even rebuilt the Master Cylinder and of course bled properly. It did what its doing before and after all the work I put in. If you look more closely at the pic of the old one it is sunken in around the rod and if i compare by "feeling" around (on the new one ) that accordian looking rubber gasket there is a solid steel cylinder around that rod that goes all the way up to that gray felt looking thing that you can see thru the circular holes of the accordian gasket you feel a solid object underneath. If I measure from the base of that accordian gasket to the top of it on the old and new the ole one is shorter by about 1 inch than the new one and that distance is the exact distance I have left to get my brake pedal into proper brake pedal height.
I'm not trying to disprove you or answer my own question, but I feel from your response you've not seen what I see. It is this sunken-in-ness on the old one that has me questioning and because whenever I press the brake pedal there is an internal popping sound coming from where the booster is under the hood whenever I push the pedal all the way down. So what you (or anyone else) think? I mean this can't be the first time these conditions have been found on an old brake booster.
searcherrr
02-16-2007, 11:25 PM
bump - No One ? Look Better At The Pics Please.
Decipha
02-17-2007, 12:01 AM
check your vac line going to the booster make sure its not deteroriated... usually when a booster goes bad the pedal gets stiff, check to see if its holding pressure... start the car and push the pedal as far down as you can, wile the pedal is down shut the car off but keep holding the pedal down for about 30 seconds... it shouldn't do down any furthur... if it does than your booster isin't air tight
searcherrr
02-17-2007, 03:33 AM
check your vac line going to the booster make sure its not deteroriated... usually when a booster goes bad the pedal gets stiff, check to see if its holding pressure... start the car and push the pedal as far down as you can, wile the pedal is down shut the car off but keep holding the pedal down for about 30 seconds... it shouldn't do down any furthur... if it does than your booster isin't air tight
The vac line that was on there was suspected to have a leak from visual inspection, but a leak test produced no noticeable leak sounds. I replaced the vac line (with built-in check valve) anyway. I have already performed the 3 booster function tests in the service manual and the booster passes all 3, but that isn't my concern. I don't think the manual covers a test that should be in there. I do suspect there is a vacuum leak somewhere else in the engine as I cannot get the base idle to set correctly even with the booster out of the loop. I plan on doing a HOT vac leak test after the engine is fully warmed up. I've done all my other tests while the engine was cold, but I was thinking the only time when I can't get a stable idle is when the engine is fully warmed up. So if I do have a leak somewhere else you think it contributed to the failing of the booster? You think I could pull the rod of the booster back and that it would reset the diaphargm in place from the "too far inward" position it is in now? See if you look at that accordian looking gasket you can see how sunken in it is. Think I can pull it back?
The vac line that was on there was suspected to have a leak from visual inspection, but a leak test produced no noticeable leak sounds. I replaced the vac line (with built-in check valve) anyway. I have already performed the 3 booster function tests in the service manual and the booster passes all 3, but that isn't my concern. I don't think the manual covers a test that should be in there. I do suspect there is a vacuum leak somewhere else in the engine as I cannot get the base idle to set correctly even with the booster out of the loop. I plan on doing a HOT vac leak test after the engine is fully warmed up. I've done all my other tests while the engine was cold, but I was thinking the only time when I can't get a stable idle is when the engine is fully warmed up. So if I do have a leak somewhere else you think it contributed to the failing of the booster? You think I could pull the rod of the booster back and that it would reset the diaphargm in place from the "too far inward" position it is in now? See if you look at that accordian looking gasket you can see how sunken in it is. Think I can pull it back?
searcherrr
02-17-2007, 11:47 PM
BUUUUUUMMMMMP !
Come on you mean none of you mechanic tech heads out there have seen this condition on a brake booster? LOL - I guess in all the time I've been waiting for someone to confirm based on the pictures I could've had it apart and tested by now. I just think from "feeling it" and "looking at it" that its broken because it makes sense because I can't adjust my brake pedal to the proper height.
Come on you mean none of you mechanic tech heads out there have seen this condition on a brake booster? LOL - I guess in all the time I've been waiting for someone to confirm based on the pictures I could've had it apart and tested by now. I just think from "feeling it" and "looking at it" that its broken because it makes sense because I can't adjust my brake pedal to the proper height.
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