wheel cylinder rebuilding

[theclay]

OK....first off...i haven't posted in forever...been really busy.

For about the past year we've been having problems with the brake pedal going dead...once it was a leaky fitting...next it was air in the lines...then we realized that our mechanic put in DOT 3 brake fluid from the start since he didnt know about the importance of using the girling/castrol. So we finally figured out that the brake fluid was causing the problem. We rebuilt the master cylinder and flushed the system thoroughly with the new fluid. That fixed the problem for a while...then i lost pedal again. When i did have pedal it was pulling to the right, so we suspected the right front wheel cylinder as being the problem, since it had not yet been replaced from the beginning. I replaced that, and that solved the problem temporarily. Now we are back to the same problem. I need to rebuild all the wheel cylinders.

Long story short, the parts houses have the kits, but they list them as being front and rear specific. Is there any real difference between the front and rear cylinders other then the way the fitting is cast?

Besides that...anything else i could try to fix the brakes...?

[CanuckIIA]

I just checked the Rovers North catalogue and they are different part numbers. I know that the cylinders are different on every corner and I am guessing that the bore in the cylinder is different front and back to "balance" the system better.

My 1964 88" has rear backing plates, shoes and drums on all four corners, but the cylinders on the front are still from the fronts and I think Mark Nault from Wise Owl mentioned this specifically because it is important.

Check your cylinder bores and hopefully they won't be as bad as mine were. I had to buy a hone. Oh well, at least I have one now.

[onslow]

Originally Posted by theclay

OK....first off...i haven't posted in forever...been really busy.

For about the past year we've been having problems with the brake pedal going dead...once it was a leaky fitting...next it was air in the lines...then we realized that our mechanic put in DOT 3 brake fluid from the start since he didnt know about the importance of using the girling/castrol. So we finally figured out that the brake fluid was causing the problem. We rebuilt the master cylinder and flushed the system thoroughly with the new fluid. That fixed the problem for a while...then i lost pedal again. When i did have pedal it was pulling to the right, so we suspected the right front wheel cylinder as being the problem, since it had not yet been replaced from the beginning. I replaced that, and that solved the problem temporarily. Now we are back to the same problem. I need to rebuild all the wheel cylinders.

Long story short, the parts houses have the kits, but they list them as being front and rear specific. Is there any real difference between the front and rear cylinders other then the way the fitting is cast?

Besides that...anything else i could try to fix the brakes...?

If you can strech to it dont rebuild the cylinders as in my experience it never lasts long however the same can be said for cheap pattern parts,if you can get them genuine lucas/girling/lockheed components should be used for the extra cost is worth the trouble,ensure the brake cylinders are fitted the correct way up dont laugh ive seen it on a lwb!!!

Secondly general rule of thumb for series brakes 109 lwb 2.6/1 tonne fronts are the biggest followed by standard 109 fronts then 109 rears which are the same as 88 fronts then 88 rears,a small number of landrover brake master cylinders can only be bled with a compressed air brake bleeder although I find this to be most effective on all landrover vehicles.

[theclay]

forgot to mention i have a 65 IIa 88...so its more worthwhile just to get all the cylinders replaced?

Also...as of now i have zero brakes...its a miracle i havent gotten into an accident...so theres no such thing as streching it anymore...AB sells all four for around 100 bucks..but they arent the genuine girling...worth it or not?

[pickuprover]

Yes replace all wheel cyclinders, especially if they are aluminum cast ones, as you cannot really hone the cyclinders. As well, you might want to replace the flex hoses, sometimes they get weak which allows the tube to swell, taking fluid and power away from the cyclinders. If they have never been replaced, I might order them as well if I were you.
The other thing to check would be the cams. Although some will say this never happens, it has to me, so.... The snail cams set the distance of the pads to the drum. If one is closer to the drum, it contacts first, and causes the thruck to pull. You said that rebuidling the cyclinder temporarily fixed your problem, but maybe it was that the cams are vibrating one brake tighter, and the other side loose. (definately more noticeable if this is on th front.) If there is not sufficent tension on the snail cams, then replace....

[CanuckIIA]

Adjusting, (or at least checking) the cams is VERY recommened. I did new shoes, front drum, flex lines and rebuilt front cylinders last fall. I finally took it to my mechanic because I just couldn't get it bled worth a damn. But now, it brakes about as well as my 4Runner.

Makes me wonder how bad my 4Runner brakes have gotten.

Looking back, if I had more money last year, I would have liked to go for new cylinders, as I imagine my home done hone job couldn't have been top quality. But no sign of leaks yet.

[antichrist]

The rears are 1" dia, fronts 1 1/4".
You can hone the cylinders if done properly.
For $100 I'd probably just replace them all. For a bit more, replace the MC as well.
Definitely replace the flex lines unless they are near new. Old flex lines are one of the biggest culprits for soft pedal. They may look fine, but internally they are swollen, and your pedal travel get's used up pushing the lines back to orginal size, with little left to move the cyl pistons.

[RageRover]

Not to get too far off track but, I was told in my Hydraulics Brakes session at college, that you can mix DOT 3 and DOT 4, the only difference is that DOT 4 has a higher boiling point than DOT 3, but not by much. So I am not sure why DOT 3 is would affect the brakes in the hydraulic action.

They do have this stuff called DOT 5 which is like a synthetic brake fluid used in high speed/high performance motor sports, and that is purple colored. It has a rather high boiling point, and cannot be used in a conventional system or more-or-less mixed in with DOT 3 or 4.

They also have this stuff called DOT 5.1 which can be mixed with DOT 3 or 4.

Just my two cents.

[MPi-KMS-72]

Pat,

The problem with regular DOT3 in a series is it can eat the high natural rubber seals. You need Girling or Castrol LMA OR Silicone Brake fluid.


The Clay,
The wheel cylinders are a different size F+R because it is a sort of brake proportioning. They are interchangeable- that is you could swap Cylinders F to R but you really don't want to do that.

I honed the cylinders I had on my 1965 88"-they were old, I'm not sure how old but after careful honing and new seals they've lasted another 10 years. Usually I find that the major cause of replacement around here is broken and seized bleeders/fittings. The bores are almost always recoverable as long as they aren't too pitted, if you flush your brakes frequently or use silicone brake fluid it really cuts down on the amount of water in your brake cylinders and hence on the corrosion in them.

[RageRover]

Matt, yeah now I understand what you're saying. I also forgot too that the Series Rovers had 4 wheel drum brakes.

Also I didn't exactly know that you can overhaul wheel cylinders too. I know that overhauling a caliper is a compromise to buying new ones, didn't know you could also do the same with wheel cylinders.

[pickuprover]

Make sure you check to make sure that the cylinders are cast iron, not aluminum if you are planning on honing them.... (a magnet will tell you which is which if there is a question..) you cannont use a brake hone on the aluminum ones... (although if they are not in too bad of shape, a scotch bright pad and some very, very fine emery cloth has been used, but only for a quick fix to get you home...).

[onslow]

Originally Posted by MPi-KMS-72

Pat,

The problem with regular DOT3 in a series is it can eat the high natural rubber seals. You need Girling or Castrol LMA OR Silicone Brake fluid.


The Clay,
The wheel cylinders are a different size F+R because it is a sort of brake proportioning. They are interchangeable- that is you could swap Cylinders F to R but you really don't want to do that.

I honed the cylinders I had on my 1965 88"-they were old, I'm not sure how old but after careful honing and new seals they've lasted another 10 years. Usually I find that the major cause of replacement around here is broken and seized bleeders/fittings. The bores are almost always recoverable as long as they aren't too pitted, if you flush your brakes frequently or use silicone brake fluid it really cuts down on the amount of water in your brake cylinders and hence on the corrosion in them.

DOT3 is fine in any LR product it will NOT affect seals in anyway the DOT system is only a way of grading performance,hence DOT 2 and DOT 3 fluids where the original grades used by landrover so mixing them is fine just be carefull with some fully synthetic oils as previously stated and some vehicles like old jaguars used a special mineral oil which is to be avoided (not easy to come by anymore anyway)

[MPi-KMS-72]

Originally Posted by onslow

DOT3 is fine in any LR product it will NOT affect seals in anyway the DOT system is only a way of grading performance,hence DOT 2 and DOT 3 fluids where the original grades used by landrover so mixing them is fine just be carefull with some fully synthetic oils as previously stated and some vehicles like old jaguars used a special mineral oil which is to be avoided (not easy to come by anymore anyway)

You would think so but
no that is actually not true- at least here in the USA. They are performance grades not compositional gradings. Generic USA DOT3 can and has wreaked havoc with Series Land Rover seals here in the USA for many years. This might be an issue only with USA DOT 3. I don't know about UK DOT3 products but I do know I've seen seals left in samples of different fluid and the US DOT 3 was clearly not compatible. Like all things it might vary by brand of fluid, and by the composition/source/brand of the seals. A well meaning friend of mine happened to fill my resevoir with Walmart "tech" brand DOT3 last summer and my clutch hydraulics took a crap shortly thereafter. I've known many other people who have run into the same problem so there definately have been some compatibility issues.

BRAKE AND CLUTCH FLUID:
Castrol LMA or other DOT 4 brake fluid

Change interval: Once a year on an average.

TIP: DOT 4 brake fluid is hygroscopic. This means it will absorb moisture that will damage brake components. In very damp climates or with extended deep wading the brake fluid should be changed more often to achieve maximum service life from brake and clutch hydraulic systems. You would not need to change the fluid as often in arid climates.

TIP: Brake fluid is very corrosive on paint. Take care not to spill brake fluid on a painted surface. If some spills clean it up immediately and wipe with a wet cloth to dilute any residues.

TIP: Castrol LMA brake fluid was designed to work with your rubber hydraulic components and provide maximum trouble free service life. However any DOT 4 brake fluid will work. You should not use DOT 3 brake fluid in your system.

DOT5, or Silicon brake fluid will work properly in your Land Rover's hydraulic systems but do NOT mix it with any other hydraulic fluid. It has the advantage of not being corrosive to paint or hygroscopic. The disadvantages of using DOT 5 brake fluid are expense and that it can carry tiny air bubbles in the fluid for a long time. This can make the hydraulic systems very hard to bleed for a reliable hard pedal.

TIP: If you should decide to convert from DOT 4 hydraulic fluid to DOT5 fluid you must replace all the rubber parts of the brake system. The different types of brake fluids affect rubber components differently. A seal that has been immersed in DOT4 (or DOT3) fluid will almost always leak when later immersed in DOT5 fluid.

The best time to switch over is when your old brake system is tired and in need of new master and wheel cylinders. Don't to forget to replace the flex hoses at the same time.

http://www.britishpacific.com/series...Rovertech.html

Brake fluid
• Castrol LMA ** use DOT 4 fluid only — not the more common DOT 3

http://www.robisonservice.com/servicedep/rover_tips.asp

Remember- USE CASTROL LMA GTX or other DOT4 eq. or better brake fluid, NOT DOT3 in your British car! DOT4 should be changed every 2 years.
DOT5, Silicon is OK too. I'm currently running some long term tests on it, with good results. It should perform much better for a low usage or stored vehicle as it won't absorb water, and therefore should result in very low corrosion levels. DOT4 may be preferable for high use, or competition vehicles.

http://www.lrfaq.org/Series/Drivetra...Operation.html

The original brake cylinders used natural rubber in the seals. When Series Rovers were new, owners were strongly cautioned to use only Castrol/Girling LMA, a vegetable-based fluid. Any other fluid would deteriorate the seals, resulting in loss of braking. Girling eventually changed to a neoprene seal which is compatible with modern, glycol-based brake fluid. As long as the entire system has the modern neoprene seals, a DOT 3 or DOT 4 fluid can be used. Unless you have some old parts fitted or in the kit box, you don't have to use vegetable-based fluids (Castrol/Girling LMA) anymore. I use DOT 4 brake fluid.

http://www.bayourovers.com/trick14.html

From: David Cockey <dcockey@tir.com>
Subject: Re: Dot4

Mike Johnson wrote:

> >Don't ever, ever, ever use ANYTHING other than the Castrol girling
> juice
> >of the gods.... the other stuff will rot your rubber inards on the
> whole
> >brake system..
> Another chapter from the book of urban myths. But to each their own I
> suppose. People feel a sort of religious attachment to certain
[ truncated by list-digester (was 11 lines)]
> Champion spark plugs, oil, oil filters, octane grades, tires and so
> on.

Maybe folklore, as in has a basis in fact. I've heard for 20 years or
more that Girling uses/used a different type of rubber than most other
brake part makers which is incompatible with the usual North American
brake fluid. The Castrol is compatible. I also thought DOT 3 vs. DOT 4
is a matter of boiling point, etc, and don't know if the Castrol
formulation is needed to get the DOT 4 pertformance or if Castrol just
happens to be DOT 4 also. Silicon brake fluid is supposed to also be
compatible with Girling rubber. However, the usual folklore is don't mix
silicone and non-silicone brake fluid. Again, just because it is
folklore doesn't mean it is false.

One potential incompatiblity of silicone is with hydraulic brake light
switches as used in pre-67 vehicles. An item in the US British car mag a
few years ago claimed that the hydraulic pressure switches have
electrical contacts exposed to the fluid. Supposedly minor arcing can
occur each time the contacts open and this causes the problem.

Regards,
David Cockey

Date: Sat, 6 Dec 1997 22:03:39 -0500 (EST)
From: David Scheidt <david@math.earlham.edu>
Subject: Re: Dot4

On Sat, 6 Dec 1997, David Cockey wrote:

> Mike Johnson wrote:
> > >Don't ever, ever, ever use ANYTHING other than the Castrol girling
> > juice
> [ truncated by lro-lite (was 11 lines)]
> Maybe folklore, as in has a basis in fact. I've heard for 20 years or

more that Girling uses/used a different type of rubber than most other
brake part makers which is incompatible with the usual North American
brake fluid. The Castrol is compatible. I also thought DOT 3 vs. DOT 4
is a matter of boiling point, etc, and don't know if the Castrol
formulation is needed to get the DOT 4 pertformance or if Castrol just
happens to be DOT 4 also. Silicon brake fluid is supposed to also be
compatible with Girling rubber. However, the usual folklore is don't mix
silicone and non-silicone brake fluid. Again, just because it is
> folklore doesn't mean it is false.

Girling components are said to contain a higher amount of natural rubber
than american stuff. (The folklore about that is the British wanted to
support the colonial rubber industry.) DOT 3, DOT 4 and DOT 5 are
standards about performance, not content. DOT 3 and DOT 4 are both almost
exclusivly glycol or glycol-ether based, depending on brand. DOT 5 stuff
is silicone, though there is said to be a glycol based DOT 5. The
differences are mostly the boiling points of the stuff (from memory, don't
shoot me if I wrong:

Dot 3 dot 4 dot 5
dry boiling pt 400 448 500
wet 285 310 356
). If your brake fluid boilds, the bubbles are compressable, which goes
the sort of spongyness we all know and love. It should be noted that
these are american standards. (Lucas-)Girling have a seperate set of
standards, which cover not only boiling point, but also things like how
quickly they eat the seals. So there are DOT-3 fluids that won't eat
brake components, and DOT-4 that will. If the can or spec sheet says that
it meets all Girling standards, then you are probably safe. Castrol
GT-LMA meets these standards, so you should be able to use it with no
problems. So does the Prestone Super-Heavy duty fluid, which I have never
used.

Silicone brake fluids are a different kettle of fish. Silicone is pretty
inert, so your seals are safe. Silicone is also not hyrdoscopic (doesn't
absorb water), so you will have less corrosion of pistons, cylinder walls,
and bleed screws. It also doesn't need to be changed as often, partially
off-setting its much higher cost. (About US$15 a litre, as opposed to
US$5/litre for GTLMA) The problem with silicone fluids is they are very
slightly more compressable than the glycol based stuff. The
compressablity also increases with temperature, indpendently of actual
boiling. No one seems to use silicone fluids in high performance
situations any longer, due to these concerns. They are also not
recommended for ABS-equippped vehicles for this reason. (But also because
they are expensive, so no one uses them, so manufactures don't test with
silicone, so don't want to risk a lawsuit.) There is probably not much
reason not to use silicone fluids in Series truck, other than it is quite
expensive. Drain, flush with isopropyl alchol, and dry with dry
compresed air. Replace all of the rubber bits, which makes the fluid look
cheap, but this is necesary to make sure that you don't have any gylcol
fluid in the system.

Brake fluids are essentially miscible, so don't need to worry too much
about mixing types. However, if you put any glycol-based in a silicone
system, you are adding water (or the potential for water), which is why
you are using silicone in the first place, right? If you have to get
home, though, it is not going to cause a catastrophic failure.

I should add the usual disclaimers: I am not an qualified expert on brake
fluid, hydraulics, or most things automotive. I also use nothing but
Castrol GTLMA. It is religion folks, not science.

Regards,

David/mr. sinclair (with all new rubber hydraulics since september)

http://www.fourfold.org/RoverWeb/lro...971207.html#12

From shute!@mtcamm.monsanto.com:car-list-rejects@transfer.stratus.com Mon Nov 2 11:35:37 1992
Return-Path: <twakeman@apple.com>
Date: Mon, 2 Nov 92 09:26:09 -0800
From: Teriann J. Wakeman <twakeman@apple.com>
To: lro@transfer.stratus.com, sgm@hplb.hpl.hp.com
Subject: Re: Brakes need pumping for good stop !!

You need DOT4 brake fluid. Castrol LMA does the job. You need this fluid
because the British empire included a number of colonies that produced
natural rubber. Several trade agreements later, your Land Rover brake hoses
were made of natural rubber. DOT3, the slightly cheaper more common
variety destroys your rubber brake hoses.

As an asside, you really should flush out your brake & clutch hydrolics
one a year. Brake fluid is hydroscopic & the water it picks up can corrode
the hydrolic pistons.

You might spens some time looking for leaks around the cylinders. If you fix
the softness and it comes right back, suspect the master cylinder.

As long as you keep the rubber side down, and fluid in the resivour there is
no angle that should let air into your brake line.

TeriAnn

Series II 109

http://www.fourfold.org/RoverWeb/lro...1992/9211.html

[pickuprover]

Originally Posted by onslow

DOT3 is fine in any LR product it will NOT affect seals in anyway the DOT system is only a way of grading performance,hence DOT 2 and DOT 3 fluids where the original grades used by landrover so mixing them is fine just be carefull with some fully synthetic oils as previously stated and some vehicles like old jaguars used a special mineral oil which is to be avoided (not easy to come by anymore anyway)

Onslow, I would dissagree.... everything I read about the DOT 3 is that it will eat your rubber seals... as far as I am concerned, if it is a series truck then the castrol LMA or girling fluid is the only ones to use...

[MPi-KMS-72]

You really wouldn't think this would be a problem, especially in today's litigation prone society. I was always sceptical of the warnings myself. "surely this must have been solved long ago? This is probably the continuation of a 30-40 year old issue that has evolved into a wife's tale..."-

Maybe it has finally been solved but I know I've seen seals damaged and hoses swelled so much there was no room for fluid to flow through them. Maybe we just have really crappy DOT3 here in the States? Maybe some vender's here sell crappy seals that originate in India or Thailand or some other place where they are natural rubber? Maybe some people have used NOS seals that were 30 years old?