'68 Brake booster removal

[BAC]

Hi All,
I think the brake booster in the '68 might have a vacuum leak so want to take it out to inspect and/or replace.

Ideally I'd like to remove it without unplugging the brake lines from the master cylinder so I don't have to bleed the $*&%ing thing when I put the booster back.  So far I've managed to remove all the nuts under the dash and taken out the bolt in the engine bay so the booster wiggles freely on the mounting studs. 

So far I've tried removing the master cylinder from the booster but can't get enough clearance.  Also tried angling the booster with master cylinder still attached every which way but still can't get enough clearance to free the mounting studs in the firewall without the master cylinder fouling on the shock tower.

Is it possible to get the booster out this way and if not, what's the best method in order to minimise the amount of extra work I'll have to do when I put everything back?

[GEOFF289]

Good luck Brian.  While mine is a '66 I tried to do the same thing, leaving the lines attached, to adjust the pushrod and couldn't. 

There are, of course, much smarter people than me on here so maybe there is a way but I couldn't find it.

[sms777]

Why are you so scared of bleeding the brakes? If you have a small aircompressor buy one of those inexpensive Air Boy vacuum bleeders it makes bleeding a one man operation. I can bleed the whole car with one of those in 10 minutes. Besides your car will benefit from fresh brake fluid through it's system anyway. Otherwise you can keep on fighting with brakes lines attached and you will bend everything and scratch the hell out of your shock tower.
Also a lot easier if you remove the shock tower brace.   

[BAC]

Why are you so scared of bleeding the brakes?

Not scared, just would be nice once in a while to be able to do a job on the car without having to dismantle several other things as well.   

If it can't be done without taking off the brake lines then so be it, just wanted to make sure there wasn't an easier way to do it first...

[Reborn67]

Any chance to bleed and refresh brake fluid is always a good thing, haven't heard of one of those vacuum bleeders sms777 suggested but l will look into one of those,, l have always used an old cut down broom handle to wedge between the 'depressed brake' pedal and the base of the front seat, if there is nobody about to help, a bit tedious but you can do it by yourself...,

[sms777]

Here you go Andrew:

[Reborn67]

Sweet, thanks

[GEOFF289]

That Airboy looks pretty schmick but they're $100 or so and might not be justified if you're not bleeding brakes all the time like Chris is. There are way cheaper options that will do the same job if you only need it occasionally.

I have one like this https://www.ebay.com.au/itm/Hand-Held-Brake-Bleeder-Tester-Set-Bleed-Kit-Vacuum-Pump-Car-Motorbike-Bleeding/253307804680?hash=item3afa525c08:rk:1:pf:0 that has worked fine for both brakes and my clutch.

(You can borrow it Brian if you need to)

[BAC]

I have one like this https://www.ebay.com.au/itm/Hand-Held-Brake-Bleeder-Tester-Set-Bleed-Kit-Vacuum-Pump-Car-Motorbike-Bleeding/253307804680?hash=item3afa525c08:rk:1:pf:0

You can borrow it Brian if you need to

Thanks for the offer Geoff, pretty sure I have one similar to yours stashed away in the garage - somewhere...

[evan]

+1 for the power brake bleeder. Saved me so many headaches!

Mine looks like this & cost me around $85 IIRC. I don't even bother bench bleeding the M/C any more.

Evan.

[GLENN 70]

I have done it before but by taking the master cyl off 1st with the lines still on . But here is the cheeky way I did it . I had problems even getting the master cyl off and past the booster studs so I cut the studs back a bit ,to the ends of the nuts really ,that gave me enough room to get the master cyl off and out of the way . Other wise take the lines off and bleed the brakes which is no big deal really . The studs hang out about 12 mm ,  I also took that  side of the export brace off to get into it easier . I also put a towel down the side of the tower so I didn't scratch it .  It's up to you how you do it ,the right way or cheeky way 😳 .If the car is going before you go through that check the booster and check valve 1st .  You can do this with the booster still on . Question what's it doing ? .

[BAC]

I had problems even getting the master cyl off and past the booster studs so I cut the studs back a bit ,to the ends of the nuts really ,that gave me enough room to get the master cyl off and out of the way

I thought of that option but I'm not totally convinced it will work for me.  I have the Midland booster which has the thick metal spacer between the booster and the master cylinder so it sits further out and you can't cut as much off the studs.  I'll have another look and measure to see if it might be a goer.

check the booster and check valve 1st .

Did that earlier with my hand vacuum pump.  Check valve holds vacuum fine but the main body of the booster does not.

what's it doing?

Not providing as much assistance as it should.  I'm down a bit on vacuum anyway due to the cam but still around 15-16" at idle. Booster is probably leaking a little all the time but when you hold the brake pedal down you can hear a slow hissing sound coming from the area of the firewall where the booster is.

[GLENN 70]

Does the pedal go hard or is it hard all the time ? .  Have you tried with the booster vacuum hose blocked and disconnected ? To see if their is any difference . You might have to give in and take the lines off the master cyl and take it out ,then the booster .

[BAC]

Does the pedal go hard or is it hard all the time?

No way I'm going to put those nuts back on the booster studs under the dash now, but from memory it was hard all the time.

Have you tried with the booster vacuum hose blocked and disconnected ?

Yup, and put it back on again pretty quick - the pedal was rock hard so the booster is supplying some assistance.

You might have to give in and take the lines off the master cyl and take it out ,then the booster.

Will have a look at shortening the studs first and if that's no go then off come the brake lines...

[BAC]

Booster is OFF with brake lines still in place!   

Thanks Glenn. 

[shaunp]

Mustangs pretty much gravity bleed them self

[GLENN 70]

Well how did you do it ????

[BAC]

Well how did you do it ????

The cheeky way as recommended by your good self. 

[BAC]

New booster is in and working great.   

My old leaky Midland (rebuildable) is up for grabs if anybody needs it.