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Discussion Starter #1
Hi!

I am going to replace the front spheres on my '91 Turbo next week, and have been studying the IETIS Manual and the "Crew'ed Jottings" #11 from the australian RR fforum for guidance. The info is pretty comprehensive, but I still have a couple of questions:

Removing Spheres:

1. In order to remove the horizontal #2 accumulator, apparently the valve body for #1 accumulator has to be removed. Is there any way not to have to do that?

Replacing the LHM and bleeding the system:
I'd like to replace the LHM fluid, as I have no idea how old it is. I'll be working alone on a car lift with the wheels off the ground.

1. The RR manual calls for first bleeding at points A & B at the accumulator valves. Then opening bleeding points at the pressure limiting valve, front wheel calipers and pressure switches and then depressing the brake pedal and starting the engine. Can I bleed these point one after the other, or do the all need too be open simultaneously? I can see myself making a royal mess of the workshop I am borrowing...
2. Same question for the rear brakes.
3. When bleeding the suspension struts, the car has to be on the ground, but does it matter for the other points?
4. How much fluid are we talking about? Is it easiest to remove the lids of the reservoirs too facilitate topping up?


Cheers

Es
 

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Watching with interest as I will be doing similar on my '89 Turbo R in the next few weeks (+front discs and pads). As to bleeding I think this prior post is the best I have seen:

 

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The "official instructions" for bleeding these cars turns the process into a Rube Goldbergian exercise that's far more complicated than it need be. Bleeding from the end points (calipers and rams) ensures that all the mid-points have had fluid pushed through them already.

Here is a link to the SZ Brakes & Hydraulics folder on my Google Drive. Many years ago Richard Treacy, who now owns a spare parts business in Australia, SpurParts, wrote up instructions for bleeding SY/SZ brakes easily, and I ended up splitting that information up to be for each era of car and putting a couple more details in. But the bulk of this information came directly from Mr. Treacy.

Everyone I know who's used these instructions has had zero issues with the process. So look at the three documents in the above noted folder, and particularly the easy bleeding instructions. The other two TSDs can come in handy at times, too.
 

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Hi!

I am going to replace the front spheres on my '91 Turbo next week, and have been studying the IETIS Manual and the "Crew'ed Jottings" #11 from the australian RR fforum for guidance. The info is pretty comprehensive, but I still have a couple of questions:

Removing Spheres:

1. In order to remove the horizontal #2 accumulator, apparently the valve body for #1 accumulator has to be removed. Is there any way not to have to do that?

Replacing the LHM and bleeding the system:
I'd like to replace the LHM fluid, as I have no idea how old it is. I'll be working alone on a car lift with the wheels off the ground.

1. The RR manual calls for first bleeding at points A & B at the accumulator valves. Then opening bleeding points at the pressure limiting valve, front wheel calipers and pressure switches and then depressing the brake pedal and starting the engine. Can I bleed these point one after the other, or do the all need too be open simultaneously? I can see myself making a royal mess of the workshop I am borrowing...
2. Same question for the rear brakes.
3. When bleeding the suspension struts, the car has to be on the ground, but does it matter for the other points?
4. How much fluid are we talking about? Is it easiest to remove the lids of the reservoirs too facilitate topping up?


Cheers

Es
I recently replaced the front spheres on my 1990 Turbo R and had to remove both valve bodies in order to remove the spheres as the spheres were too tight to remove while in place. I did bleed the brakes per the instructions provided by guyslp and the instructions worked perfectly. Joe
 

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In order to remove the horizontal #2 accumulator, apparently the valve body for #1 accumulator has to be removed. Is there any way not to have to do that?
No way, there is no space unless you raise the engine in order to access #2
I completely remove #1 as a complete unit, then, removed #2 as a complete unit, then separated the spheres from the valve body on the workbench. My spheres were also too tight to remove in the car.
How much fluid are we talking about? Is it easiest to remove the lids of the reservoirs too facilitate topping up?
A lot, I purchased 10 Litres, and I remember that I used 9. I removed the lids since it takes forever to fill via the special adapter hose.

I followed the brake bleeding video parts 1 and 2; the result was perfect:

 

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By the way, for those removing their spheres and valve bodies, pay careful attention to the torque tightening figures for the spheres to the valve bodies.

It is astounding just how often the "gorillacizing" method of tightening is used - tighter is better. Well, very often, it absolutely isn't and makes life far more difficult when later maintenance is needed.

The torque figures are generally far lower than many might think. I doubt that there's much, if any, difference for the torque figure (but do check) for the sphere to valve body than there is for the SY series cars, and in that case it's 55-60 ft-lbs, which is just the slightest bit tighter than the brass lug nuts for the wheels (45-50 ft-lbs).

I also always use just the tiniest bit of anti-seize on the threads and go for the low end of the torque range.
 
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Discussion Starter #7
Thanks so very much guys!
I've managed to organise an "assistant", which should make the procedure somewhat easier. And also ordered another 8 litres of LMH....
I'll let you know how it goes!

Cheers
Es
 

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Few remarks. On the Turbo R it was too tight, I had to remove sphere and valve body and replace some seals.connected to the valve body.
On the Continental R, with a little less place, they were factory tight and I could remove them with a sort of big oil filter key home made. Both sphere can be removed without removing vavle body. I did it and I am just a car enthousiast, not a talentuous mechnic as some of you. It is a quesiton of milimeter, but it is possible.
Lift the car, secure it safely, tage left frony wheel out...
Do not forget to pump about 100 times on brake pedal to depressure the system. Also you can use the bleeder on valve body, but pumping is an OBLIGATION

Bleeding:
Myself I bleed 10 bleeders alone, with engine iddling and a system ( for ex piece of woond) to block the barke pedal against front seat.
Front wheels / 2 caliper per wheel / 2 bleeder per wheel / 4 bleeders at front
Rear wheel / 1 caliper per wheel with double " piston" / 2 bleeder high and low per wheel / 4 bleeders at rear
2 Brake pressure switches / They should be under the bonnet on right side / 2 bleeders / very important to bleed them

You may have brown LHM when bleeding

Open slowly bleeders to avoid emulsion

Personnally I do not bleed suspension, normally it is self bleeding and circulating, not stuck like in brakes ( calipers...)

If you bleed suspension, be very carrefull as rear car may collapse .

Thrankly, if you bleed all brakes and switches, you are done. Brake pressure switches are in my opinion more important than suspension.

9liters LHM is fine, make sure to bleed enough to have LHM green new. Make sure to add LHM in tank regularly
 

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Discussion Starter #9
Thanks Jean!
Question though, do you bleed all of the points at the same time, or one after the other?

Es
 

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basically one at a time on the same circuit. Bleeding is also controlling where the air goes. so starting right after a pump and working away towards a wheel caliper on the same circuit will rid most of the air.
Same for the second circuit.
I would go for a drive for additional circulation and bleed again.
 

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I forgot..one of the worst practices is to overtighten the bleed nipple. Some are tightened so much, they no longer seal.
Check the torque, it is very low, so snug until dry mode.
 

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Discussion Starter #12
basically one at a time on the same circuit. Bleeding is also controlling where the air goes. so starting right after a pump and working away towards a wheel caliper on the same circuit will rid most of the air.
Same for the second circuit.
I would go for a drive for additional circulation and bleed again.
Hi Wraithman,

That makes more sense now!

Es
 

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That's exactly why bleeding at the end points until you have clear, bubble-less fluid is not only much easier, but guarantees that all points in the system ahead of those end points are clear of any air, too.

I will never understand why the weird bleeding method in the workshop manual was ever cooked up. I don't even bleed from the "mid-points" if that's all I've disturbed. I still bleed from the end points. It may use a little more fluid, but you are certain when the end points are looking good that everything between the pump and those end points will be, too.
 

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I bleed one by one. A respected specialist told me that cars with ABS need to be bled from the closest caliper to the ABS to the farest. That was also, as far as I remember th official procedure in the IETIS. As you have it you could see it.

Yes overtight bleeder destro them. I sugeest first you try to unblock bleeders, one by one, sometime they are hard. You need a 6 faces ( don't know how you call that) key not to dammage the edge of the bleeder). I have always bleeders in advance from different types in case there is an issue while bleeding, either damaging the bleder, either finding one with signs of worn.

I start with the 2 brake pressure switch, open very very slowly, no need to brake for those 2 , just engine idling. There is a lot of pressure there, avoid absolutely emulsion by opening too fast too much. Slowly is the best.

I take a lot of LHM from the 2 switches, to empty the 2 LHM tanks untill the low level light goes on. Make sure they work and your flotters work. Like this I strt bleeding calippers with fresh LHM

So in order:
2 brake pressure switches
2 bleeder front left wheel
2 bleeders front right wheel
2 bleeders left rear wheel
2 bleeders right rear wheel

Check regularly LHM level, each bleeder, sometime the flotter is not moving because stuck then suddenly disappear.
Refill LHM with original can with special pipe.

If you get brown LHM, at callipers or bleeeders, it means it is really old .
 

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One thing we all know; the brake/hydraulic systems on both SY and SZ cars are complex with many "corners" to hide the random bubble.
I usually burb whatever system I'm I'm working on, even midway. The temptation and satisfaction of "I got ya" moment when the rogue air bubble pops out is hard to resist.
 

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Discussion Starter #16
Hi!
I successfully replaced the spheres this evening, which was much less of a hassle than I had expected :)
I had to loosen the lover valve body, but other that it was easy.
My "assistant" will join me tomorrow for a bit of bleeding, which will no doubt be fun!

How does one dispose of the the old spheres?

Cheers

Es
 

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How does one dispose of the the old spheres?
Anyway do not throw it to the trash ;) Some months ago someone did it in Poland. Someone other found it and call for police, thought that it is hand granade or something like that. Anti-terrorists sappers analyzed that it was just used sphere from Citroen :D
 

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Discussion Starter #19
I got my local mechanic to dispose of the spheres. Haven't seen any bomb disposal crews in the neighbourhood yet :)
 
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