Do-it-yourself booster overhaul (1 Viewer)
- Thread starter lostmarbles
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inkpot
SILVER Star
Howdy! I learned a neat trick that is an option to clamping the housing. Use vacuum at 25 - 30 # like for air conditioning. Hook it up to the vacuum port that goes to the engine. Mount one side of the housing in a vice, twist the top half with a BIG breaker bar to get the cam locks released, and then slowly bleed down the vacuum and the inner spring will open the can right up. After replacing the inards, turn on the vacuum first, then set the top on using body weight to compress the spring. Once the seals make contact, the pump will compress the rubber gasket enough to allow you to engage the camlocks. This will work for the older brake boosters that just have a barrel hoop style ring holding it together. I have done a 72 FJ-40, and a 76 FJ-55 this way. John
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- #23
Thanks for the comments. I was sidetracked today so I didn't even look at that booster. (I can get sidetracked alot so there's no guarantees on when the booster work will be finished.)
I went to a local 4x4 event instead. Here's a pix of what I was watching. The cruiser pix inserted in all 4 corners are all 40 series cruisers taking part in today's competition.
Don't you feel ashamed going to a 4x4 event in an ordinary car? Especially in the likes of a Nissan Pulsar? - (Oh - the drawbacks of tinkering with your fourby.)
Thanks again Mark for the tickets to the event (if you are reading this).
I went to a local 4x4 event instead. Here's a pix of what I was watching. The cruiser pix inserted in all 4 corners are all 40 series cruisers taking part in today's competition.
Don't you feel ashamed going to a 4x4 event in an ordinary car? Especially in the likes of a Nissan Pulsar? - (Oh - the drawbacks of tinkering with your fourby.)
Thanks again Mark for the tickets to the event (if you are reading this).
- Thread starter
- #24
Back to the booster work. It's a fine day today so my outdoor workshop is open.
Here's a photo of the syringe I find indispensable for brake/clutch work. It enables me to "cleanly" empty the reservoirs of fluid. You can even use it to flush/suck debris from the very bottom of the reservoirs where it tends to settle out.
I've also included a pix "trekker" (fellow MUD member) supplied of himself in one of his recent posts. Judging from the pix I'm sure he'll be able to supply you with used syringes like mine.
Here's a photo of the syringe I find indispensable for brake/clutch work. It enables me to "cleanly" empty the reservoirs of fluid. You can even use it to flush/suck debris from the very bottom of the reservoirs where it tends to settle out.
I've also included a pix "trekker" (fellow MUD member) supplied of himself in one of his recent posts. Judging from the pix I'm sure he'll be able to supply you with used syringes like mine.
- Thread starter
- #25
Next step was to simply push the piston/diapragm assembly out from the firewall-half of the shell. (Just hand pressure).
Does anyone know what lubricant was used during assembly? There's still a lot of it there and it looks very much like Vaseline!
Then I pried out the circular ring (with a small screwdriver) which revealed 2 felt rings and a foam ring that comprise the air filter. (Actually from the photo above it appears I did this BEFORE not AFTER.)
Does anyone know what lubricant was used during assembly? There's still a lot of it there and it looks very much like Vaseline!
Then I pried out the circular ring (with a small screwdriver) which revealed 2 felt rings and a foam ring that comprise the air filter. (Actually from the photo above it appears I did this BEFORE not AFTER.)
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- #26
Then I removed the zinc-plated plate (3 screws) and the washer located on the other side.
This revealed three fingers that could simply be lifted out.
This revealed a circlip.
And that picture was the last I thought I'd ever see of that circlip!!!!! Wouldn't ya know it. No sooner had I lifted the circlip clear than it simply vanished from the end of my circlip pliers. And it didn't even have the courtesy to say "p-i-n-g" to indicate where it was going. Neither was there any sound to indicate where it had fallen. (That can be the case with outdoor workshops!!!)
This revealed three fingers that could simply be lifted out.
This revealed a circlip.
And that picture was the last I thought I'd ever see of that circlip!!!!! Wouldn't ya know it. No sooner had I lifted the circlip clear than it simply vanished from the end of my circlip pliers. And it didn't even have the courtesy to say "p-i-n-g" to indicate where it was going. Neither was there any sound to indicate where it had fallen. (That can be the case with outdoor workshops!!!)
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- Thread starter
- #27
Well. This is one of the luckiest days I've ever had in my outdoor workshop. I didn't consider it worthwhile even looking for that circlip. But then, even with my failing eyesight (oops I forgot I am upsetting other age-compromised people with my remarks about my age) - There it was bringing joy to my heart - Lying in the drainage channel at the bottom of my driveway.
Once the circlip was off, that valve/piston thingy (whatever it is - I should really study the manual while typing this!) was able to be simply pushed out through the other end of the diaphragm assembly/contraption.
There is a washer sitting beneath the circlip that I have put back on the shaft for the photo. (Taking these photos does slow me down but then they should help me reassemble it all correctly too.)
Now I must go off back outdoors to carry on (and give my good-for-nothing son back MY computer).
Once the circlip was off, that valve/piston thingy (whatever it is - I should really study the manual while typing this!) was able to be simply pushed out through the other end of the diaphragm assembly/contraption.
There is a washer sitting beneath the circlip that I have put back on the shaft for the photo. (Taking these photos does slow me down but then they should help me reassemble it all correctly too.)
Now I must go off back outdoors to carry on (and give my good-for-nothing son back MY computer).
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- #28
I've used a die grinder with a mini cutting disk to engrave the match marks deeper so they won't be obscured by painting:
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- #29
Wrong, wrong, WRONG
Now for confession time! I've found I've been wrong on two counts. (-at least that I've found - Please tell me if there are more).
Firstly, that tear in the boot does matter. It allows dust and grit to reach the plastic "sleeve" that slides in and out of a seal as the booster diaphragm moves.
Secondly, The gasket between the master cylinder and booster ISN'T there to do anything really. (Certainly not to aid the seal around the m/cyl pushrod in stopping air from entering as I had thought). This is evident from the drain groove pressed into the booster shell beneath where that gasket sits. This groove must be there to allow fluid leakage from the m/cyl to drain into the engine bay rather than get sucked into the booster. (But I note that some MUD members still complain of fluid getting sucked into their boosters.)
Next week I intend taking the diaphragm and seals (which look good) into a local clutch/brake specialist (along with that torn boot) to see what they can supply. (XXXX aren't likely to be any use are they????)
Now for confession time! I've found I've been wrong on two counts. (-at least that I've found - Please tell me if there are more).
Firstly, that tear in the boot does matter. It allows dust and grit to reach the plastic "sleeve" that slides in and out of a seal as the booster diaphragm moves.
Secondly, The gasket between the master cylinder and booster ISN'T there to do anything really. (Certainly not to aid the seal around the m/cyl pushrod in stopping air from entering as I had thought). This is evident from the drain groove pressed into the booster shell beneath where that gasket sits. This groove must be there to allow fluid leakage from the m/cyl to drain into the engine bay rather than get sucked into the booster. (But I note that some MUD members still complain of fluid getting sucked into their boosters.)
Next week I intend taking the diaphragm and seals (which look good) into a local clutch/brake specialist (along with that torn boot) to see what they can supply. (XXXX aren't likely to be any use are they????)
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Nice lawn you got there 
snip...
I've also included a pix "trekker" (fellow MUD member) supplied of himself in one of his recent posts. Judging from the pix I'm sure he'll be able to supply you with used syringes like mine.
That's not me... I was just poking a little fun in my post while installing my transmission! For the record, this is Gregg Valentino. He is in the Guinness Book of Records as the man with the biggest biceps in the World. His arms have a circumference of 28 inches... I'm really a skinney bugger.But I do use syringes like the type you used. These things are great for sucking up stuff.
Not back to your regular scheduled program!
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- #32
Not back to your regular scheduled program!
Ah. Glad you're not offended by my reference to your photo Trecker. I tried to PM you twice (belatedly seeking permission to do that) but I think I failed in both attempts. (The messages never got stored in my "sent messages" folder so I presume they never went. I was then too scared to try a third time in case you would receive all 3 and I'd have proven that I'm an idiot!)
- Thread starter
- #33
How the booster works
I always like to work out how things work. It enables me to avoid making costly mistakes in reassembly.
Consequently I've been thinking about how this booster works and I think I've got it. (Tell me if I'm wrong?)
The vacuum on the mastercylinder side of the diaphragm is present all the time (if your vacuum system is working properly). This means that all "control" must be on the pedal-side.
When you're not using the brakes, the air valve situated in the "booster rod assy" ensures the pedal side of the diaphragm is also under vacuum so the big spring keeps the diaphragm back towards the pedal side. (No boost pressure.)
When you put your foot on the brake, that pedal pressure is transmitted straight through (via the rod assy) to the main (outer) piston in the mastercylinder to apply the brakes on all 4 wheels. At the same time, the air valve opens the pedal side of the diaphragm (by the movement of the rod assy within that black plastic sleeve attached to the diaphragm plate) to the atmosphere (and closes it to the vacuum) allowing atmospheric pressure to apply pressure on the diaphragm plate. This pushes against the circlip on the booster rod assy to apply extra pressure to the mastercylinder piston (above that applied by your foot). (The air enters the pedal side of the diaphragm through the holes in my torn rubber boot (and the underlying air filter pads) that used to sit inside the cab behind the brake pedal.)
Releasing the brakes shuts off the air and re-applies the vacuum to the pedal side. (Any air that was there is then immediately sucked out by the vacuum.) So the diaphragm moves back.
This is a bit of a simplification because the movement of the diaphragm (in response to atmospheric pressure when the brakes are applied) tends to re-shut the air valve. In this way, FULL boost pressure is applied only when FULL pedal pressure is applied.
How did I do? Have I got it right?
I always like to work out how things work. It enables me to avoid making costly mistakes in reassembly.
Consequently I've been thinking about how this booster works and I think I've got it. (Tell me if I'm wrong?)
The vacuum on the mastercylinder side of the diaphragm is present all the time (if your vacuum system is working properly). This means that all "control" must be on the pedal-side.
When you're not using the brakes, the air valve situated in the "booster rod assy" ensures the pedal side of the diaphragm is also under vacuum so the big spring keeps the diaphragm back towards the pedal side. (No boost pressure.)
When you put your foot on the brake, that pedal pressure is transmitted straight through (via the rod assy) to the main (outer) piston in the mastercylinder to apply the brakes on all 4 wheels. At the same time, the air valve opens the pedal side of the diaphragm (by the movement of the rod assy within that black plastic sleeve attached to the diaphragm plate) to the atmosphere (and closes it to the vacuum) allowing atmospheric pressure to apply pressure on the diaphragm plate. This pushes against the circlip on the booster rod assy to apply extra pressure to the mastercylinder piston (above that applied by your foot). (The air enters the pedal side of the diaphragm through the holes in my torn rubber boot (and the underlying air filter pads) that used to sit inside the cab behind the brake pedal.)
Releasing the brakes shuts off the air and re-applies the vacuum to the pedal side. (Any air that was there is then immediately sucked out by the vacuum.) So the diaphragm moves back.
This is a bit of a simplification because the movement of the diaphragm (in response to atmospheric pressure when the brakes are applied) tends to re-shut the air valve. In this way, FULL boost pressure is applied only when FULL pedal pressure is applied.
How did I do? Have I got it right?
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- #34
Solutions sometimes come to me in the middle of the night and such was the case here.----- The rubber in the old diaphragm is so soft, thick and pliable that it MUST be just as good as the day it was made. Being liberally coated with lubricant during the original assembly, not having to move much (due to proper brake maintenance during its lifetime), and living in the dark with a vacuum on BOTH sides (now I know how the booster works I can say "both") for almost all its life - means it has been effectively sitting in "controlled atmosphere storage". (In my refrigeration background this term is used for getting the maximum storage life for chilled apples!) So I won't bother trying to replace it. (I had been "umming and ahhing" over this decision.) So I've bagged it like a "crime-scene specimen" in a snap-lock plastic bag and will put it on a storage shelf - Well Err -on the upturned concrete mixer bowl - in my filthy/cluttered garage.
On the subject of vacuum, my BJ40 has always held vacuum well. I can leave it parked for 2 weeks and it'll still have good vacuum. I know this because whenever I pump the brakes A LOT without the engine running (like during brake line bleeding work) the "poor vacuum" alarm will s-c-r-e-a-m at me when I next try starting it.
On the subject of vacuum, my BJ40 has always held vacuum well. I can leave it parked for 2 weeks and it'll still have good vacuum. I know this because whenever I pump the brakes A LOT without the engine running (like during brake line bleeding work) the "poor vacuum" alarm will s-c-r-e-a-m at me when I next try starting it.
So, lostmarbles, I've seen several age remarks in your postings. How old are you? that is if you don't mind me asking
that is if you don't mind me asking
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- #36
More "verbiage" (Good word choice MACE!)
You'll have noticed I've altered my thinking about reusing all the old stuff. Ideally I'd like to be confident of another 30 years fault-free operation once this booster is finished.
This brings me to today's chore - Which is approaching the local clutch/brake counter-salesperson for any generic parts I can use.
I know I've posted in support of the "I hate my Toyota Parts Salesperson" thread but really I sympathise with such people. My current full-time job is a "bus driver" so I know how rude people can be. (I often have fun with such people in my own way.)
Really why should a vehicle manufacturer provide parts for a vehicle indefinitely once it has rolled off their production line? And being rude to people harms yourself more than them by creating "low self-esteem".
A "plus" of the parts problem is that it makes our vehicles rarer and more desirable as fewer and fewer remain on the road!
So today I'll front up to the partsperson with a friendly smile and armed with all the information to try and make their job easy.(- Hey - Why can't bus passengers think like this and have their blasted fares ready when they board the god-damned bus???)
I'll have the torn boot (in another crime-scene bag). I can tell them that the booster-outer-shell to m/cyl-pushrod seal I want has OD 41mm and ID 12mm. I can also tell them the firewall-side-booster-shell to diaphragm-plate-sleeve bush/seal has OD 2 inches and ID 1 1/2 inches (Yeah. Seems to be a mixture of metric and imperial)
Will let you know how I get on in the next thrilling instalment.
You'll have noticed I've altered my thinking about reusing all the old stuff. Ideally I'd like to be confident of another 30 years fault-free operation once this booster is finished.
This brings me to today's chore - Which is approaching the local clutch/brake counter-salesperson for any generic parts I can use.
I know I've posted in support of the "I hate my Toyota Parts Salesperson" thread but really I sympathise with such people. My current full-time job is a "bus driver" so I know how rude people can be. (I often have fun with such people in my own way.)
Really why should a vehicle manufacturer provide parts for a vehicle indefinitely once it has rolled off their production line? And being rude to people harms yourself more than them by creating "low self-esteem".
A "plus" of the parts problem is that it makes our vehicles rarer and more desirable as fewer and fewer remain on the road!
So today I'll front up to the partsperson with a friendly smile and armed with all the information to try and make their job easy.(- Hey - Why can't bus passengers think like this and have their blasted fares ready when they board the god-damned bus???)
I'll have the torn boot (in another crime-scene bag). I can tell them that the booster-outer-shell to m/cyl-pushrod seal I want has OD 41mm and ID 12mm. I can also tell them the firewall-side-booster-shell to diaphragm-plate-sleeve bush/seal has OD 2 inches and ID 1 1/2 inches (Yeah. Seems to be a mixture of metric and imperial)
Will let you know how I get on in the next thrilling instalment.
- Thread starter
- #37
Tis very easy for you to find out.So, lostmarbles, I've seen several age remarks in your postings. How old are you?
I did hide it from my "public profile" for a while but my age is back there now.
But I'm really only a youngster. The supervisor at work who I get on with best is 74. And he can easily "drink me under the table". He presently often drinks a dozen beers a night while watching the "rugby world cup" on TV and is still fully mentally-alert. (My goal too but it's s-l-i-p-p-i-n-g a--w--a--y.)
I want never to "grow up". I look at some of the "restrained/pompous" people out there and wonder how you ever get like that.
Nothing as childish as "playing in the mud" really is there?
- Thread starter
- #38
What did I gain with my smile and good preparation when fronting up to the partsman??? Well - Sweet f........all!!!!!
The shop couldn't give me any clue as to what generic replacement parts they could supply. Now mere words can't describe how I feel. I've left my beloved BJ40's very private parts on the counter for strangers to fondle willy nilly!!!!!
Say......... Perhaps there's a connection explaining why so many of my passengers board the bus looking so grumpy and without their fares/tickets ready???? I'll have to ponder that one.
Without the booster, my mind is starting to wander from the "job in hand".
Say...... You folks in "the states" and Canada must struggle to avoid getting an "inferiority complex". You must feel like the last in a line of siblings, getting hand-me-down clothes and getting to use the last of the dirty bathwater. I mean ---- Did you realise that not only are you driving cruisers that we (in New Zealand) have thrashed to death, but you're even getting the days that we've been using before you.
For instance - Today is Tuesday 16 October here. I bet you're still using "yesterday".
Another thing while I'm at it - "Days" are shorter than "months" - which in turn are shorter than "years". If you look closely - and think hard - there's a natural progression at work there. I say this because some of you get it wrong. You don't express a date in this "natural progression order". In other words, you MUST express today's date as 16.10.07 (like in the bottom RH corner of my photographs). OOOPs. Forgot! Your date is yesterday's ---- Start again - ---You MUST express today's date as 15.10.07. (Lesson over.)
Sorry! My scarred mind (from decades of abuse) wanders wildly when not confined to an immediate task.
I'm to ring back the partsman. I'll let you know how I go.
The shop couldn't give me any clue as to what generic replacement parts they could supply. Now mere words can't describe how I feel. I've left my beloved BJ40's very private parts on the counter for strangers to fondle willy nilly!!!!!
Say......... Perhaps there's a connection explaining why so many of my passengers board the bus looking so grumpy and without their fares/tickets ready???? I'll have to ponder that one.
Without the booster, my mind is starting to wander from the "job in hand".
Say...... You folks in "the states" and Canada must struggle to avoid getting an "inferiority complex". You must feel like the last in a line of siblings, getting hand-me-down clothes and getting to use the last of the dirty bathwater. I mean ---- Did you realise that not only are you driving cruisers that we (in New Zealand) have thrashed to death, but you're even getting the days that we've been using before you.
For instance - Today is Tuesday 16 October here. I bet you're still using "yesterday".
Another thing while I'm at it - "Days" are shorter than "months" - which in turn are shorter than "years". If you look closely - and think hard - there's a natural progression at work there. I say this because some of you get it wrong. You don't express a date in this "natural progression order". In other words, you MUST express today's date as 16.10.07 (like in the bottom RH corner of my photographs). OOOPs. Forgot! Your date is yesterday's ---- Start again - ---You MUST express today's date as 15.10.07. (Lesson over.)
Sorry! My scarred mind (from decades of abuse) wanders wildly when not confined to an immediate task.
I'm to ring back the partsman. I'll let you know how I go.
- Thread starter
- #39
Just rang up the auto brake/clutch specialist. They say it could take "a couple of days" to find any generic parts that will fit my booster.
That's the beauty of dealing with a small business staffed by enthusiasts. (At least I'm hoping they fit that category. It certainly seems like they do because a large profit-focused company wouldn't be bothered with me - Would they?)
One of the benefits of owning a vehicle for decades is that I could give them the old details off the booster identification label (that have since worn off). That is:
44610-60030
OG 04770
AISIN SP**** CO JAPAN
The *s represent letters/numbers that were indecipherable even back then (when I recorded those details).
That's the beauty of dealing with a small business staffed by enthusiasts. (At least I'm hoping they fit that category. It certainly seems like they do because a large profit-focused company wouldn't be bothered with me - Would they?)
One of the benefits of owning a vehicle for decades is that I could give them the old details off the booster identification label (that have since worn off). That is:
44610-60030
OG 04770
AISIN SP**** CO JAPAN
The *s represent letters/numbers that were indecipherable even back then (when I recorded those details).
pbgbottle
Forum Lifer
not sure if you would be interested but toyota lists a booster rebuild kit for the booster . a major one or a minor one .also they don't list just a part # for that torn boot actually just looked closer they only show one rebuild kit for your booster ,you must have front drums ?
edit just read your last post i must of been typing when you posted it #44610-60030 =75/01-80/07 fj40/55,hj45/bj4?
booster for front drum brake
actually just looked closer they only show one rebuild kit for your booster ,you must have front drums ? edit just read your last post i must of been typing when you posted it #44610-60030 =75/01-80/07 fj40/55,hj45/bj4?
booster for front drum brake
