Brake Booster Replacement - a Hint

[courtenay]

Here's a hint if you ever have to replace the brake booster - sell the fricking car as is!! While I've removed the master cylinder from the booster, I haven't even contemplated how I'm going to get the frigging thing out of the engine compartment yet. I've been contorting my 6'3" body under the dash - 3 of the four nuts bolting the thing to the firewall are easy to get at, but the fourth (top right) is a killer!!!
Anyone interested in a rust free, low mileage (68,000kms) '80 Fi? I'm about ready to consider offers....
The good news is it's keeping me self isolated....

[SteinOnkel]

Yeah, it's a pain. But there's a trick.

Grab an impact gun and a lot of extensions. Daisy chain them. Make sure the socket is on a wobbly one. Use one hand to guide the socket onto the nut then use the other to pull the trigger.

Also, everything on these cars is much harder than on their contemporaries, I've noticed. It's like every. single. time. you are missing the last 1/4" to get a proper tool on whatever it is you are trying to loosen or tighten. How they ever assembled these cars on an assembly line is beyond me.

[spider2081]

I found the black metal plate the brake booster mounts to appears symmetrical it is not. Its important to mark the original plate and booster alignment. Then transfer the plate to the new booster retaining the identical alignment. If the plate is upside down the studs will pass through the fire wall but the boosters brake rod will not line up with the brake pedal.

Often its best to remove the driver seat when working under the dash. Replacing the booster is easier with 2 people, one inside the car and one outside.

[RRoller123]

+1 a hundred times! I had to put a long wood clamp across the plate, (inside the car) to pull it back into alignment, because it had a natural spring set into it from the stamping. Just would not align. Pain in the fing butt.

(Then after I put it in, I realized it was 90 degrees out of orientation (the brake cylinder would be over on its side), and I had to take it all out and do it again. Be careful with this! Oh the pain...)

[18Fiatsandcounting]

Agreed. I replaced the booster on my '71 a few months ago, and the car learned a few new swear words that it hadn't heard before. It can be done, but it's not for the faint of heart. As for Steiny's question of how the factory assembled these in the first place, my guess is the the booster was installed way before the rest of the interior was installed (dash, steering column, seats, engine, etc.).

-Bryan

[RRoller123]

That makes sense.

[tdskip]

Thanks for the good tips gentlemen.

[courtenay]

Thanks for the tips, guys. Waiting for a rainy day to take another run at the mother. Got to take advantage of sunny days to get the yard in shape.

[axelbaker]

Here's a hint if you ever have to replace the brake booster - sell the fricking car as is!! While I've removed the master cylinder from the booster, I haven't even contemplated how I'm going to get the frigging thing out of the engine compartment yet. I've been contorting my 6'3" body under the dash - 3 of the four nuts bolting the thing to the firewall are easy to get at, but the fourth (top right) is a killer!!!
Anyone interested in a rust free, low mileage (68,000kms) '80 Fi? I'm about ready to consider offers....
The good news is it's keeping me self isolated....

I'll trade you. I've had my booster out and in already. It's the rest of the brake system. I can't get a good bleed. I've rebuilt or replaced all the wear parts and some of the not normally wear parts. I just can't seem to track down my bubble/leak.

Best of luck, it is doable, and it is a pain in the ass. Move the seat all the way back and make your self comfortable .... upside down.

[RRoller123]

Take the driver's seat out, well worth the minimal effort, makes it much easier to get comfortable under there, on a stack of heavy moving mats.

[courtenay]

Question for guys who have done this job - were you able to remove the booster from the top and did you have to disconnect the speedometer cable to get it out?

[18Fiatsandcounting]

Yes and yes to your questions, but I think you mean removing the clutch cable rather than the speedometer cable. The speedometer cable runs inside the car down to the transmission tunnel (that is, nowhere near the brake booster). The clutch cable is the one that runs over top the brake booster.

-Bryan

[courtenay]

Thanks, Bryan. Shows you how much I know about this job. Oh joy!
Cheers, Bruce

[RRoller123]

Just changed my Speedometer cable. It is the one that exits the passenger compartment directly underneath the brake fluid reservoir. Have to remove the brake reservoir clamp from the firewall (not drain it or anything) and carefully tilt the reservoir forward on its lines to get at the spot where the rubber grommet goes through the firewall. (on my '80)

[18Fiatsandcounting]

Thanks for setting me straight RRoller. It's been about 30 years since I've been around a 1980 or so model, so my memory dims.

So for Bruce, you may indeed have been correct and I was the one in error. Regardless, you still can remove the booster as you suggested, although it is a bit of a PITA.

-Bryan