Torque specs, vac booster
Thread Starter
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Torque specs, vac booster
Hi all 
Need some torque specs from a factory manual for the brake booster.
Namely booster to firewall bracket, and master cylinder to booster.
Been around 13 years since i have done this job, but i seem to remember 15 ft/lbs and 13 ft/lbs.
The car is 1993, but i would expect they're all going to be similar at least from 90-96.
Also, the thickness of the unmounted booster should be in the manual too, rear mounting surface to front, i need to rebuild the booster and i can't find any of the info i had on this.
Thanks all
Need some torque specs from a factory manual for the brake booster.
Namely booster to firewall bracket, and master cylinder to booster.
Been around 13 years since i have done this job, but i seem to remember 15 ft/lbs and 13 ft/lbs.
The car is 1993, but i would expect they're all going to be similar at least from 90-96.
Also, the thickness of the unmounted booster should be in the manual too, rear mounting surface to front, i need to rebuild the booster and i can't find any of the info i had on this.
Thanks all
Melting Slicks
Joined: Feb 2003
Posts: 2,667
Likes: 809
From: Saskatoon Sask.
Never could figure out why so many people here get a woody over torque specs for mundane, unimportant tasks. Put the nuts/bolts on and tighten them. Done deal! Here is a challenge - go to any shop and watch the professional techs. Observe how many times they scurry for a torque wrench doing routine R and R.
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From: Louisville, Ky
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I did a quick search and the master cylinder torque to power booster is the same 84-96, 15 ft lbs. My 85 FSM shows 15 ft lbs for power booster to fire wall.
I'm guessing the thickness dimension you're looking for is actually the one across the long bolts the FSM calls tie rods? I'm showing, for an 85, a special tool is required, J-35498. It's check dimension is 98.1-98.4 mm or 3.86-3.87 inches. Again these are from an 85 FSM.
HTH,
Joe K
ETA: found J-35498 on eBay. $12.95 not linking because you are in AUS but I'm sure they're available there.
I'm guessing the thickness dimension you're looking for is actually the one across the long bolts the FSM calls tie rods? I'm showing, for an 85, a special tool is required, J-35498. It's check dimension is 98.1-98.4 mm or 3.86-3.87 inches. Again these are from an 85 FSM.
HTH,
Joe K
ETA: found J-35498 on eBay. $12.95 not linking because you are in AUS but I'm sure they're available there.
Last edited by Joe K; Dec 30, 2020 at 11:56 AM.
Thread Starter
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
I did a quick search and the master cylinder torque to power booster is the same 84-96, 15 ft lbs. My 85 FSM shows 15 ft lbs for power booster to fire wall.
I'm guessing the thickness dimension you're looking for is actually the one across the long bolts the FSM calls tie rods? I'm showing, for an 85, a special tool is required, J-35498. It's check dimension is 98.1-98.4 mm or 3.86-3.87 inches. Again these are from an 85 FSM.
HTH,
Joe K
ETA: found J-35498 on eBay. $12.95 not linking because you are in AUS but I'm sure they're available there.
I'm guessing the thickness dimension you're looking for is actually the one across the long bolts the FSM calls tie rods? I'm showing, for an 85, a special tool is required, J-35498. It's check dimension is 98.1-98.4 mm or 3.86-3.87 inches. Again these are from an 85 FSM.
HTH,
Joe K
ETA: found J-35498 on eBay. $12.95 not linking because you are in AUS but I'm sure they're available there.
I used to rebuild a fair few of these and i never used the tool they list in the manual, i used to use calipers to measure it.
Appreciate your help mate
Thread Starter
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Never could figure out why so many people here get a woody over torque specs for mundane, unimportant tasks. Put the nuts/bolts on and tighten them. Done deal! Here is a challenge - go to any shop and watch the professional techs. Observe how many times they scurry for a torque wrench doing routine R and R.
There are many good reasons to use the correct torque specs, in this instance the part is made largely from plastic, and it is part of a critical system within the car.
Now you and any 'professional techs' can do whatever you like but i won't, and i would never suggest anyone else ignore factory advice on torque specs either.
Thread Starter
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Yep, i have done lots of them on a few different makes and models years ago before getting out of it all, i always used a torque wrench on the plastic boosters. The same booster is used on a lot of cars from the mid 80s to the early 2000s.
A wobble extention made it much easier to get in there on the right angle.
A wobble extention made it much easier to get in there on the right angle.
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Melting Slicks
Joined: Feb 2003
Posts: 2,667
Likes: 809
From: Saskatoon Sask.
Yep, i have done lots of them on a few different makes and models years ago before getting out of it all, i always used a torque wrench on the plastic boosters. The same booster is used on a lot of cars from the mid 80s to the early 2000s.
A wobble extention made it much easier to get in there on the right angle.
A wobble extention made it much easier to get in there on the right angle.
Thread Starter
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Glad you made this post. I'm interested in how you made the angle measurements to calculate the torque setting adjustment of these fasteners that you claim are "critical". 1:46 is where it gets interesting.
http://www.youtube.com/watch?v=tRR96ILGORU
http://www.youtube.com/watch?v=tRR96ILGORU
But hey, you keep goin buddy
Melting Slicks
Joined: Feb 2003
Posts: 2,667
Likes: 809
From: Saskatoon Sask.
