Brake servo & master conversion

[jezza89]

Hi all,

I have an 84 RRC with the old style master cylinder and brake booster:

https://www.aulro.com/afvb/images/imported/2016/09/1065.jpg

See the 4 bolt one as above. These are literally rare as hens teeth. I have already previously replaced my master cylinder with a newie, but turns out the booster is the problem.

Diagram of old assembly:
http://cat.lrparts.ru/1230_010502000.jpeg


Is it possible to replace the old assembly with a newer one?
I am just looking to pull off the old 4 bolt booster and master cylinder, then replace with the new 2 bolt booster (stc1286 which I have) and matching cylinder.

Diagram of new assembly:
http://cat.lrparts.ru/1230_010501920.jpeg

It looks like everything is comparable, but I will need to drill new mounting holes in the firewall for the 2 bolt servo/booster.

Has anyone done or considered this before?



Cheers,
Jeremy

[Davo]

I haven't had it done, but apparently you can get a servo rebuilt at a brake shop. Back when I was looking into it, I seem to remember the kits were available and I thought about doing it myself - though there is a bloody great big spring inside that put me off. I wound up getting a good servo from a member on here.

[Meccles]

If you contact Brookers Brakes in Maroochydore they have name and address of one guy in Sydney, who does all their booster rebuilds. And they said he could still do early RRC boosters. They said he was only person they trust to use. If you wanted to go that way. Get old booster and send it across.
Their number 07 54439305. Guys name was Sam from memory

[Mercguy]

The lockheed boosters are rebuildable if they haven't rusted through. Problem is, the kits are expensive - over 500 bucks.

A new late TRW booster isn't too pricey - about 375 or thereabouts.

I cannot see the brake pedal pivot point changing, but the worst case scenario you'd have that I can see, is that you'd need a later pedal box assembly from an RRC, and that will have the correct holes for the booster and then also the shaft length / pivot etc all matches. Personally I think a visit to a wrecker is a good idea, even if it is just for a look to see if there is any difference other than the stud pattern. and a 2nd hand booster master cyl and pedal box from a wrecker is likely to be a lot cheaper than a rebuild on your original early booster.

[jezza89]

The lockheed boosters are rebuildable if they haven't rusted through. Problem is, the kits are expensive - over 500 bucks.



A new late TRW booster isn't too pricey - about 375 or thereabouts.



I cannot see the brake pedal pivot point changing, but the worst case scenario you'd have that I can see, is that you'd need a later pedal box assembly from an RRC, and that will have the correct holes for the booster and then also the shaft length / pivot etc all matches. Personally I think a visit to a wrecker is a good idea, even if it is just for a look to see if there is any difference other than the stud pattern. and a 2nd hand booster master cyl and pedal box from a wrecker is likely to be a lot cheaper than a rebuild on your original early booster.


https://www.aulro.com/afvb/images/imported/2016/09/969.jpg
https://www.aulro.com/afvb/images/imported/2016/09/970.jpg


Didn't see the plate it all bolts to on the firewall! No drilling after all...

If I can swap the entire assembly, it should be easy! We have a couple of RRC wrecks in the family for spares... There's an 88 we have started stripping that has a newer setup... Might try and scavenge the bits...

Thanks for the tip :)

[350RRC]

Pretty sure a D1 pedal box bolts straight in, with the booster and MC you want. Someone will confirm hopefully.

DL

[Mercguy]

Having the manual trans doesn't help much, as most of the late RRC's here are auto, but that shouldn't be your main issue.

just FYI - I replaced the master cyl on my RRC earlier this year and it was about $250 for brand new gen-u-whine part.

I personally have quite rigid views about braking systems and maintenance, but not always able to perform overhauls on certain parts (because they are designed as throwaways, like late RRC master cyls)
So before you do a holus-bolus swapout, consider a seal kit for your clutch master and also see if the existing brake master can't be rescued or refurbed.
Then again, if you were going for the 'Upgrade' to vented front rotors and the dual circuit 4 piston callipers, I'd maybe also suggest considering late version defender callipers and master cyl as a substitute.

I recall doing a lot of research on this particular upgrade, and for me, obtaining the callipers (defender vented ones) was too difficult. So I went with 'overhaul and replace' and found the vented rrc setup (standard) as being adequate on the front.

What I vehemently dislike is the lack of vented rotors on the rear. I am looking for a solution to this still, using front rotors, to keep a 'factory' parts list... but it certainly doesn't rule out a future upgrade to a 2pc vented rotor / 6 piston calliper or some such.

Why you ask? because the way the setup is designed is an absolute bollocks-up by rovers engineers. Why the rotor has to be bolted to the inside of the hub is ****ing stupid. rotor change? oh, just pull your f-ing axles..... yeah really bright that is. dumbasses.

You can see why people go for 24 spline upgrades etc, so they don't have to pull out a whole axle to do a rotor change, but that still doesn't mean it was a smart idea to bolt the rotor to the inside of the hub, instead of the outside, or use a 2pc rotor, so the friction face could be removed with the hub in tact.

sorry, rant over. It's just one area where I have looked at the design methodology and noticed how dumb it really is. I know 'why' they wanted them mounted in this way, but servicability is shocking.

Have you considered the difference in dual circuit master and front callipers versus the defender single circuit master and calliper? just worth some thought.

It will depend on how you drive and whether or not you tow stuff I guess.

[jezza89]

My brakes on this car are incredibly spongy, and there is very little pressure from the assisted brakes. You really need to stand on them to get the car to stop quickly.
There is a constant hissing from the booster/master area whilst the car is running and for a short time after you turn it off - suggesting a vacuum or pressure leak.

I replaced the master cylinder a bit over a year ago on it. I noticed a slight improvement, but the issue remained.


I don't really do much towing with the old girl, maybe the odd 6x4 with mulch etc every now and then. I towed another RRC on a car trailer up from Albany though; which in hindsight was probably a bit dangerous.
I always drive to conditions and the car's/my own ability though, so it was a slow, cautious and slightly scary trip!

[jezza89]

Update-
Pulled the old booster out, and new one bolts up without problem.

Key difference is brake line orientation. I bent 3, but need 2 new lines to suit newer master.

Will get some pics up tomorrow.

[jezza89]

Update.



I fitted the new booster and a 2nd hand master.



Bolted up great. Bought a new set of lines and fitted them up.

https://www.aulro.com/afvb/images/imported/2016/12/541.jpg

As per link (http://www.rimmerbros.co.uk/Item--i-RA1195zz1)



New dot4 fluid went in and flushed the system as per rave guide.



Brakes work an absolute treat.

https://www.aulro.com/afvb/images/imported/2016/12/542.jpg

[jezza89]

Next thing on the agenda for brakes would be a brake upgrade up front to vented & slotted rotors...

But for now I've got to improve the steering, which can be another thread!

[Davo]

Thanks for taking the trouble to put up some photos. It's good to see what can be done.

[jezza89]

Update.
Have driven a bit further than down the road and back, and have found the brakes binding up a bit.

The pedal is very high and I'm only getting very limited travel.

Turns out I should have a spacer in between the booster and the firewall.

https://www.aulro.com/afvb/images/imported/2016/12/364.jpg
Number 15 in the illustration

Will need to compare pedals also as I seemed to have less problems when I pulled the pedal up

[jezza89]

With the spacer installed, the brakes work properly.

[goingbush]

Um, Copper brake lines are not legal in Australia !

[superquag]

Not arguing the point, but does anyone know "Why?" copper is not legal ?

[jezza89]

Does anyone have a link to legislation? I'm in WA so there is no regular testing etc anyway.

Link to current WA vehicle regulations here (https://www.slp.wa.gov.au/pco/prod/FileStore.nsf/Documents/MRDocument:29346P/$FILE/Road%20Traffic%20(Vehicles)%20Regulations%202014%2 0-%20[00-l0-00].pdf?OpenElement)
Not really any specific information regarding line material

These lines are a copper/nickel alloy, which is apparently OEM on many modern cars including volvos, but still digging for info.

Supposedly copper/nickel alloy lines are safer than steel as they don't rust?

[goingbush]

Apparently copper work hardens and cracks, thats what I'm led to believe anyway.

As an asides I just got my '73 Series 3 LWT registered for the first time in Australia, Its got the factory original steel brake lines, 43 years Old & not a spec of rust, had to get it approved by VASS Engineer and plated as complying with the relevant ADR's , inspected the original steel lines & didn't bat an eyelid . but looked harder & took photos of the brand new rubber hoses to make sure they complied with Aust standards .