Do-it-yourself booster overhaul (1 Viewer)

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Joined
Sep 3, 2007
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8,870
Location
New Zealand
I note from MUD that most people seem to just visit the wrecking yard and obtain a replacement 2nd-hand booster when theirs starts to give problems. But I've kinda got attached to all the original parts on my BJ40. (Also - Better the devil you know than the one you don't.) Besides, my booster is not giving me problems. It's just getting on to 30 years old without a service. - So in my books, it must need relubricating at the very least. (Yes. I never believe in the "If it ain't broke - Don't fix it" way of thinking. I believe in "Keep up the maintenance to maintain reliability".)

My garage is full of stuff like motorbikes, a concrete mixer (all in bits OF COURSE) plus lotsa tools, welders, a lathe etc - So I can't get the BJ40 in there and it stays permanently out in the weather. It's pissing down today. So I thought I'd start this thread rather than try and bring stuff inside and work on it on the kitchen table (which tends to upset the wife a tad).

Trouble is - This could get embarrasing if my "booster overhaul" turns into a disaster. (I saw that happen to a magazine contributor who was putting replacement seats in his forty series only to find after about the 2nd mag instalment that the new seat frames were too flimsy to weld onto. -- Whereapon he abandonned the whole thing.)

Here's some pix of the area to start with:
BoosterA.jpg

BoosterB.jpg

BoosterAA.jpg
BoosterA.jpg
BoosterB.jpg
BoosterAA.jpg
 
The pix were taken yesterday when it was a brilliant fine day.
I removed the air cleaner and then the clevis pin that connects the booster rod to the brake pedal.
BoosterF.jpg
I then used a big syringe (used by vets when injecting big farm animals) with clear plastic tubing on the end to extract the fluid from the reservoirs before unbolting the m/cyl from the booster, disconnecting the brake lines and removing the m/cyl.
BoosterE.jpg
BoosterF.jpg
BoosterE.jpg
 
The vacuum line was cut and the 4 nuts were removed (inside the cab) that hold the booster to the firewall - Enabling the booster to be removed.
Booster 002.jpg
Booster 002.jpg
 
The pushrod was able to be just "lifted out" from the mastercylinder side of the booster.
I then carefully removed the plastic non-return valve and grommet. I used silicon spray to help ease it out because I have read on MUD that people often break them if they're not careful.
Booster 005.jpg
Booster 005.jpg
 
I then marked the booster to ensure easy reassembly and made a device for clamping the booster halves together for disassembly/reassembly. (The bolts are mismatched because they are the only ones I had lying around.) Ah yes - I'll also have to remove that little clip before I can turn the "body connector ring" to release the two halves.
Booster 007.jpg

Booster 009.jpg
Booster 007.jpg
Booster 009.jpg
 
Well that's as far as I've got at this point in time. Except I have cleaned up the firewall where the booster sat and touched up the paintwork there. I've done little things like replacing the windscreen washer piping and altering the method by which it was held in place.
(I'm having some trouble with the pix as some won't allow me to reduce them in size low enough to be included.)
Booster 015.jpg
Booster 015.jpg
 
Now get this straight: windscreen, bonnet, mudguard, firewall etc. These are all the "queen's english". Where does your lingo come from?
 
Nice looking engine compartment, I wish you had been PO of the BJ42 I acquired from NZ ,although I am not unhappy at all with the cruiser or the seller,I got what I paid for and all is well.
 
i dont know. Somewhere not related to where I live. maybe scotland or wherabouts:D
 
Nice looking engine compartment, I wish you had been PO of the BJ42 I acquired from NZ ,although I am not unhappy at all with the cruiser or the seller,I got what I paid for and all is well.
Thanks Joe. Not sure what "the condition of 4-sale vehicles" is like for IH8MUD members elsewhere in the world but I'll bet it's mostly much the same as here. Except maybe for issues connected with "access to beach driving" (nowhere here is far from the sea so driving in salt water is often the fate of many cruisers) and "climate" (it's generally quite wet here).
Then again, some of you have salt on your roads in Winter (Fall) and we don't.
As you would have too, we have the people with the "Go hard or go home" attitude (I LOVE watching them) and those that believe a REAL 4x4 must always be dirty.
As a vehicle gets old and loses value, most people treat it with less and less respect. That is until/if it reaches "collectible status" when peoples' attitudes start to change. I think the "collectibe-status" is only just approaching for 40 series cruisers here. (That's why they're still cheap here compared to the USA or Canada.)
Good ones are getting rare though because they are being snapped up for "off-road competition work" which destroys many (at least as far as "viable restoration" is concerned.
The group here most likely to own mint-looking low mileage landcruisers (that they don't really want) are farmers. (My opinion only.) They often have sufficient income (certainly much more than I do) to replace a vehicle well before it is "knackered" and often have the shed space to simply leave it sheltered and unused till it is "discovered" by an enthusiast (like one of us).
But the average condition of a 40 series cruiser here is "pretty bad" in my view (nothing at all like the average Californian or Saudi owner's rig from what I can see on MUD ) and I'd guess you're getting some of the best of them as "NZ imports".
Cheers
 
Still raining solidly after 36 hours so my outdoor workshop is still closed. But I've figured how to load those images that were previously too large to load. One shows the tear in the boot which is the only wear/damage I've found so far. (I'll try and find a replaceent for that boot but really the tear doesn't cause any harm other than to theappearance.) The other shows the spray I used to ease the non-return valve from the rubber grommet.

Booster.JPG

BoosterG.jpg

Booster 012.jpg

The shot of the BONNET shows that I've really been misleading people so far about how clean and shiny the paintwork is. There are many parts I haven't yet cleaned up or painted.
Booster.JPG
BoosterG.jpg
Booster 012.jpg
 
Damn. Think I jinxed myself when I said the climate was wet here. It's still raining continuously after 72 hours. (Bet you Aussis are jealous though!)

Anyway in the past hour I cleared a small space in the front of the garage to work in shelter and pulled apart the booster.

While it was clamped in SST445(a) (which is my plywood special service tool) I knocked the little tab on the "body connector ring" around to the right to release the two halves.

BBO1.jpg

BBO2.jpg

This was initially hard to do (wouldn't budge) so I had to remove the booster from my SST, spray the ring with silicone, and tap the top of the ring with a hammer and punch all round, before reinserting the booster back in the SST. (Lucky I'm old and patience comes with old age.) Then it came apart easily.

BBO3.jpg
BBO1.jpg
BBO2.jpg
BBO3.jpg
 
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VERY pleased with what I found inside. After almost 30 years use, it looks like all moving parts remained lubricated and are in good condition. The diaphragm itself looks great. (Which it should do when you think about it. - It works in the dark with a vacuum on one side. Most people know that sunlight and oxygen are two things that promote the breakdown of rubber. (Mineral oil is a bigger culprit and it can't get there either.)

BBO4.jpg

BBO5.jpg

BBO6.jpg
BBO4.jpg
BBO5.jpg
BBO6.jpg
 
I thought I'd come unstuck with this project by being unable to obtain replacement parts like the seals and diaphragm. But now I think I may just reuse the old stuff (apart from that split boot) once it's been cleaned and plenty of fresh lube has been applied. (Unless I uncover more real faults.)

At this point in time, I'm not sure whether I'll use my "rubber grease" or my "silicone grease". Probably the silicone?????

BBO7.jpg

Actually, in this country I think parts suppliers WANT you to stuff up your brakes/clutch seals and boots because proper brake lubricants seem to be near impossible for me to obtain. If I ask at the counter of "XXXXXXXXXXX" (which is the largest chain-store parts supplier) their "kids" (yeah - I'm an oldie) will point me to "standard grease" and look at me cross-eyed when I question its suitability. Both the products in the photo were purchased by me years' ago from "god-knows-where".

I've still got to take apart the "black" side of the booster and I'll clean and paint outside of the shells to make the whole thing look "mint" before putting it back in the "nice corner" of the engine bay. (I'll tackle the other grimy corner with the heater fan assy next.)
BBO7.jpg
 
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Oh yeah. Something I should have said at the start. I belive this to be a "7 1/2 inch single-type AISIN booster".

Sidetracking - Working on things yourself all the time you get to think about things a lot of others don't. ------Like the fact that any leakage in the vacuum system will be represented as increased "engine blowby" since the vacuum pump discharges any air it sucks in into the engine crankcase. (Now own up - Who's thought of that?) (I should add that this applies only to diesels of course!)
:cheers:
 
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Enough with the "being old" remarks.... I use to be old myself, but I pulled out of it.......:cheers:
 
Why did you need to clamp the housing together in the wooden clamp? will it fly apart? Is it under heavy spring load? I was thinking about overhauling mine and don't want to put an eye out.
 
Why did you need to clamp the housing together in the wooden clamp? will it fly apart? Is it under heavy spring load? I was thinking about overhauling mine and don't want to put an eye out.

Good question! I thought the spring pressure must be really high too when I saw the picture of the STEEL special service tool in my Toyota Manual! (I even thought my plywood might break!) But no. The spring is quite weak as you can imagine when looking at the size of it in the photos. (It would certainly "shoot apart" without the clamp but I wouldn't think with sufficient force to cause injury.)
However the clamp does need to be reasonably sturdy because it must SQUASH the rubber diaphragm that also acts as the "seal" between the 2 halves during reassembly. (Without the pressure, you'd have great difficulty turning the "body connector ring" to hold the reassembled booster together.)
My manual shows great care being taken with the torque applied to the clamping bolts on the Toyota SST too. But the shells of the booster are really very solid and I believe my plywood would break before I was ever able to apply sufficient "squashing pressure" to distort the thick pressed-steel shell. So I can't see any point in this fussiness either.
:cheers:
 

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