Brake Booster Replacement - a Hint

[courtenay]

Epilogue...just realized I should have capped this off...
The starting issue was due to the distributor cap being loose. Simple fix...
Bleeding the brakes was a long process due to the plunger coming out of the booster not being adjusted quite right. It was out too far and wouldn’t allow fluid to get to the front brakes. Took the master cylinder off and turned it in a couple of turns and all was well. Took awhile to figure that one out!

[davidbruce]

Bruce, thanks for taking the time to post your epilogue. Too often members take the time to offer help but never hear the final outcome.

[geoff]

well I am finding all this very helpful because I am now convinced that I need to replace the servo.
Am I scared - well a little - but I have just replaced one of the exhaust pipes under the front of my Citroen GS so I have already experienced a few levels of this hell, so I am going to go for it.
Can anyone confirm that there is no possibility of repairing the servo - so I can get one on order - or is it worth removing it first and taking a look inside?
cheers
geoff

[18Fiatsandcounting]

Can anyone confirm that there is no possibility of repairing the servo - so I can get one on order - or is it worth removing it first and taking a look inside?

Given that new servos are less than $100, I'd just go ahead and order one. From what I hear, the issue is usually that the rubber bellows inside the unit has a hole or tear in it. While you might be able to find some way to repair this, I've never seen anyone selling repair parts, so it could be risky. In other words, the "fix" might be OK for a few months and then another issue would appear and you'd be back to square one.

However, I'm assuming that you've verified that the issue is not the vacuum hose that leads from the intake manifold up to the servo? With age, these often develop leaks. Or simply a loose connection on one end of the vacuum hose?

And yes, removing the servo will indeed test your mettle and patience...

-Bryan

[geoff]

thanks Bryan. I am sure it is not the hose, so I will go ahead and order one. After recently fitting the exhaust to my Citroen GS I am ready for this; let us see how Italian problems compare with french ones !
cheers
geoff

[courtenay]

You might want to consider replacing the master cylinder as well. It's old - and not that expensive.

A couple of hints....

Getting the booster out and in is a real challenge. You do not have to remove the clutch cable or speedo cable. You should disconnect the fuel line and move it out of the way. You will have to twist, turn and pull hard on the booster to get it out - and repeat getting it back in.
Remove the backing plate from the booster before you try to get the unit out - and put it back on once you get the new unit maneuvered back into place. Mark the orientation of the plate before you take it off. It only fits one way.
On my replacement unit, the little locking nut on the plunger coming out of the booster had to be removed in order to get the plunger at the correct setting to connect to the master cylinder. If the plunger is extended too far, you will not be able to bleed the front brakes.
Take the front seat out to work under the dash. The top right nut holding the booster is a PITA. Needs a long extension and a flex knuckle on your socket wrench. Getting it back on, with the spring bracket will involve some swearing and will no doubt require some installation fluid both during and after the job.
Good Luck!!

[SteinOnkel]

For the interior nuts, two 1/2Inch extensions and an impact gun are your friend.

[spider2081]

Remove the backing plate from the booster before you try to get the unit out - and put it back on once you get the new unit maneuvered back into place. Mark the orientation of the plate before you take it off. It only fits one way.

I made this mistake and thought the mounting plate was symmetrical, its not. For everything to align properly the relationship of the brake booster, the mounting plate and the firewall openings is dependent on the mounting plates proper positioning.

[geoff]

I live in France and my usual suplier who is in the Uk tells me that new servos are no longer available - although he does say that some are being sold in europe but are not very good. What are your thoughts- are they readily available in USA and can someone please suggest a supplier for me to copntact.
thanks
geoff

[courtenay]

I live in France and my usual suplier who is in the Uk tells me that new servos are no longer available - although he does say that some are being sold in europe but are not very good. What are your thoughts- are they readily available in USA and can someone please suggest a supplier for me to copntact.
thanks
geoff

I got mine from Vicks, but Auto Ricambi has them as well. I'd check both to ensure shipping arrangements.

[18Fiatsandcounting]

Just to give you one more option for suppliers:
https://www.midwest-bayless.com/p-21969 ... l-new.aspx

-Bryan

[geoff]

well today I removed the old sevo and it was a ba###rd of a job - but I did it without removing anything other than the master cylinder and yes, the seat. I was interested to read that Courtenay suggested removing the backing plate from the servo before trying to pull it out from the firewall. In principle this would indeed help but is it really possible to do that?
I will investigate this before I start the installation of the new one - when my hands - and back have recovered.
What I reallly hate is scratching the paintwork on the firewall and putting all that strain on the cables and pipework in order to do the job.

[18Fiatsandcounting]

I hear you, Geoff. For me, there is no easy way to remove the booster. My method: Remove the carb. Get the clutch cable out of the way. Remove the master cylinder. Remove the driver's seat. Contort your body and remove the 4 bolts that hold the booster to the firewall. Remove the clip and pin that hold the brake booster rod to the brake pedal. Curse and swear some (preferably in Italian). Pull the booster out from the top. Quaff a beer or two.

-Bryan

[courtenay]

well today I removed the old sevo and it was a ba###rd of a job - but I did it without removing anything other than the master cylinder and yes, the seat. I was interested to read that Courtenay suggested removing the backing plate from the servo before trying to pull it out from the firewall. In principle this would indeed help but is it really possible to do that?
I will investigate this before I start the installation of the new one - when my hands - and back have recovered.
What I reallly hate is scratching the paintwork on the firewall and putting all that strain on the cables and pipework in order to do the job.

It is possible, because I did it. You have to rotate it to undo the 4 bolts that are holding it on and then reverse the process once you get the servo back past all of the crap that’s in the way....which is much easier without the backing plate attached.
Good luck!
Bruce

[courtenay]

Rereading your post, you remove the backing plate after you’ve removed the servo from the firewall but before you try to manoeuvre the bloody thing through the crap that’s in the way...