Javelin brakes

[pat lockyer]

Paul if you go back to DOT 3/4 and all the system is relativly new then i would just renew all the seals in the wheel cylinders and master cylinder.
fit new brake hoses and flush the system with a vacum bleeder is favorit.

Years ago silicone seemed the best thing for cars and military vehicles that had long times of not being used, now the probs with the stuff have come to light it is not to be recomended.
If it was the best thing since sliced bread most manufacture's would use it.
It seems that only one use it and that is the Harley Davidson motor bike.

Never never use it with a modern car that has ABS.
If you go rallying or raceing use DOT 5.1 or you may end your day rather early.

[Forumadmin]

Well I have to reply to that. I have done 15 years racing and rallying with Silicone on Alpine stages that would test any set of brakes and stages in Morocco that saw other cars boiling their brakes.
After the trouble with failed wheel and master cylinders that I had with Glycol based fluids, I will never use Glycol in my Jowetts.

[pat lockyer]

I would like to hear what the JCC LTD would say on this subject, if silicone is used by recomendation and a fatality etc occured through an accident and silicone was proved the caused would they or others get sued [remember Jowetts have single not dual braking]

Will look up new guides lines on non standard use of products and mechanical changes to vehicles with regard to insurance cover,small print no doupt.

[Keith Clements]

JCC LTD would not recommend anything; it is totally at the discretion of the member what they put in their car. If anything, the liability would be on the seller or manufacturer of the fluid.
Since many parts on the car are in some way modified, and in every case with a better and safer design. insurance should not be a problem. If you are worried, declare it to the insurance company.
I will say it again. Old cars that are left for long periods with glycol in the braking system are more likely to have failing brakes through leaking or sticking cylinders. The insurance company could probably determine that you have not renewed brake fluid every 24 months as stated on the can! So where are you then with cover?
My personal experience, and take this advice totally at your own risk, is to use Silicone. I am not the world's expert; use the internet to make your own mind up. There is no such thing as an expert, only informed opinion. You may have to read and learn about many chemical and physical subjects, take advice from many learned sources, make your own decisions on the quailty of those sources and weigh up the balance of opinion and risk across many criteria. I have done that and you know my decision. I have put my life on the line with that decision many, many times.

[pat lockyer]

I will say it again. Old cars that are left for long periods with glycol in the braking system are more likely to have failing brakes through leaking or sticking cylinders. The insurance company could probably determine that you have not renewed brake fluid every 24 months as stated on the can! So where are you then with cover?

Keith in reply to the above, i personaly find the way to cover any possible insurance probs is to use what the mamufactures Jowett specify.
Use DOT 3/4 glycol [or synthetic higher spec] change every two years as recomended or stated on the can.
Not a hard job.

To use silicone it should still be changed more frequently due to its failings.
If failure within the braking system was proved silicone the cause, the insurance companys would have a field day!
Why risk it in the first place.
Just change the recomended fluid [Dot 3/4] as stated every two years.
Hope this helps you and others to enjoy the highways and byeways in total relaxed trouble free motoring.

[Keith Andrews]

Both Mineral and silcone brake fluids are good products IF USED and MAINTAINED CORRECTLY
Silicone is for high end towing (transporting a 65 ton army tank), heavy vechiles, and higher end racing application.
Silicone has a wide temp range use and works under exterme low temps (Artic) It also has a far higher compression rating, thu under normal and mid range racing appilcations one will not notice any difference.
Silicone like mineral based requires regular changing every 2 yrs.

Mineral/glycol Will do any normal usage and up to mid range racing and towing caravans etc. Mineral based, because of the gycol content absorbs miosture, this is not a problem if the system
is in good order..no leaks
Containers are kept sealed
Caps kept on master cylinders while breeding
Dont EVER reuse fluid.
If a leak occurs, replace ALL the fliud.

If a vechicle is not reguarly serviced regardless of the type, seals and other problems can occur with both...

A race car, after a meet, not only has engine serviced (often even between races) but brake cooling systems all stripped and checked before the next meet.

A vechile if stored for more than 6 months, regardless of fluid type should have the brakes checked....It issue is not what fluid is used but rather seals sticking, distorting over time.,,, A vechile stored should have regular engine starts, work the brakes and roll the wheels anyway...If u have crossplys put the vechile on blocks, otherwise they will get flat spots (radials dont)

Both Keith and Pat are correct....without regular maintance as per factory manuals and reconmendations of the fluid manufacture, and something goes wrong...insurance can go out the window...u dont want to hit a Lamborgini

OK the above is strickly by the book..
There is a huge safety margin built into both products...A brake system in top order regardless of the type of fluid will last well beyond the 2 yr margin..Im sure if many where to admitt have taken out to well over 5 yrs without problems for decades. I dont reconmend the practice.

Run which ever you choose...it is the correct maintaince that is the issue.
Personally
In the camaro (400hp 3600lbs and tow upto 1 1/2 tons tare), and all our other cars I run mineral based.
If I was to race NASCAR or heavy V8s speeds up around 150mph, endurance racing (200 miles plus)or running around the Artic circle I would be using silicone....

[pat lockyer]

It also has a far higher compression rating, thu under normal and mid range racing appilcations one will not notice any difference.

Keith A, regarding the above bit i dissagree.
As silicone fluids are compressible then the pedal would have a mushy feel and in most cases a slightly more pedal travel.
I can give some tips on useing silicone to give the best resaults but am not in favor of the stuff.

Hope keiths luck does not run out!

[Keith Andrews]

Keith C s luck?...no such thing as luck...the effort put in determines the action. lol
Brakes do not fail due to fluid choice in normal cars like his yours and mine...
They fail because maintenance is not carried out or not carried out correctly.
Both systems are good as each other.

As to choice...well its like the Ford /chev Intel/AMD
Sure there are slight differences, but not what we would notice.
And like the above, silicone / mineral dont mix yet they both work.

Discussions like this are good...
I learn a lot at the same time.
And no doubt those who read such debates get to see understand the different points of view then can make their own balanced choice...with a few tips along the way.

[pat lockyer]

I was refering to what had been said by Keith C with silicone needing no maintenace re post =

Posted: Sat Aug 12, 2006 1:02 pm Post subject:
If you use silicone there should be no need to bleed or do any other maintenance, unlike other fluids, as the silicone does not attract the moisture and cause ruting or condensation in the cylinders. However, regular use is always better for the mechanical parts.

I call this luck, it will be just a matter of time before &^%$&*(&()))Bang!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Keith Clements]

My issue with glycol is that even if you do change the fluid every two years (which, by the way, I did used to do) I found that after leaving a car unused for six months caused the wheel cylinders to rust. This was because they were coated in a thin film of glycol that absorbs moisture. Also the boundary where the seal finished also oxidised, or sulphated, the aluminium of the cylinder. Of course, if you use the brakes, this boundary moves and so polishes off any oxidant/sulphate. After such a period of non use the brakes would invariably stick on, or worse, leak where the oxidation was bad.

I have had no such problems with silicone. In my research I have not seen anywhere that silicone fluid should be changed regularly. Fluid that I have taken out when overhauling the system prior to a major rally has always been clean, unlike when using Glycol.

Simply changing fluid I do not think is good enough. You should make sure that all cylinders, including the master cylinder, are cleaned. Also take off and clean out the reservoir that can harbour a host of nasties. Fit a fluid level warning sender into it.

Check the brake springs, wheel bearing seals (or use Admax b3 grease) and the drums.

We seem to have disagrement on the relative compressability of both fluids. Can anyone point to a quantiative analysis of them please? I doubt any difference would be noticeable; but if we have the numbers we can probably work it out! Put it this way, my Jupiter and Javelin brakes seem to be better than most.

Regarding 'if Silicone was the best then manufacturers would be using it'. Possibly not, as it costs twice as much and they would not have so much service revenue. Anyway, for a much used car Glycol is adequate. Also modern systems may well not be suited to Silicone.

[pat lockyer]

My issue with glycol is that even if you do change the fluid every two years (which, by the way, I did used to do) I found that after leaving a car unused for six months caused the wheel cylinders to rust.My issue with glycol is that even if you do change the fluid every two years (which, by the way, I did used to do) I found that after leaving a car unused for six months caused the wheel cylinders to rust.

Reply to Keith C.
This happening in such a short time i can only put down to useing the car through a ford or similar with water being being pressent when the car was laid up.
This is not good for either types used but luck may be with the silicone in this instance.

Some tips on not useing the silicone.Dot 5.
The society of automotive engineers standard j1703 testing of fluids and brake components.
Regarding elastomer compatibility,brake manufacturers depend on there elastomers to swell up to 5% to properly seal.
With glyco this happens consistontly as they were engineered for glyco at the OEM level.
Silicone is now well known for its inconsistent swelling with elastomers and somtimes the brakes can start to leak after changing over to silicone.
because three different types of rubber can be used in brake systems if swelling agents have been added to the silicone fluid, they do not act consistontly.
Other failings is that silicone may not lubricate pistons as well as glycol + other points already mentioned before.

If you have a servo fitted and as most servos do in time,start to leak fluid into the inlet side[vacum] when the seals leak.
If you run silicone and when this burns within the engine the silicone is formed into silica SAND, this will quickly wear down the internal parts of the engine! another recked engine!
Glycol will not.

As for cost being high for a reason for manufacturers not to use silicone this cannot be as DOT5.1 was developed at great cost by the manufacturers and is almost i think as expensive as silicone but far exceeds it in many ways.
Stay with dot 3/4 and change the fluid every two years or every six months if brakes are submerged in water!

[PAUL BEAUMONT]

Hey guys, this is getting a bit heated isn't it? Maybe we should all back track a bit to a few basics. Brakes are essential to a motor car of any vintage (and to good health) I personally am not a great fan of fiddling around with original specifications unless there is good reason to do so, but here surely the point needs to be that Brakes, INCLUDING FLUID need maintaining like the rest of the vehicle. More than that, sudden changes in performance, sudden one sided pulling, sudden loss of fluid etc NEED INVESTIGATING IMMEDIATELY. It is worth remembering that if the vehicle is used regularly changes can occur very slowly and imperceptably. KEEP AWAKE and if you feel that your brake performance has deteriorated then INVESTIGATE AT ONCE. For the vehicles that we run and the use that we put them to is there a need for long life fluid?. Surely it is better to spend a bit less a bit more often. I would prefer to spend time and money being sure that everything is working rather than trusting what it says on the tin!
Then again, I run a Bradford which may have crude caps (Mr Wills) and buckled rims with stretching studs, but does have brakes operated by steel rods! BRING BACK GIRLING MECHANICALS say I!!!!!!!!!!!!!!!!!

[paul wilks]

I think I have inadvertently opened up a can of worms by asking what, in all honesty, I thought was a straight forward question about my braking system.

I think on reflection I will be renewing with silicone and watching what happens. If 'things happen' which shouldn't then I will probably have no other option than to renew all brake seals and hoses and revert to Dot3/4. Please pray for me that that doesn't happen!

In the longer term perhaps I should sell the Javelin and buy a Bradford(?)


Paul

[Keith Andrews]

Hey guys, this is getting a bit heated isn't it?

I think I have inadvertently opened up a can of worms by asking what,

Nope....Its a balanced discussion, and everyone is making good pionts and arguements that have substance

Brake failure.....u die its worth a discussion.

Then again, I run a Bradford which may have crude caps (Mr Wills) and buckled rims with stretching studs, but does have brakes operated by steel rods! BRING BACK GIRLING MECHANICALS say I!!!!!!!!!!!!!!!!!

Fix the buckled wheels, rebuild the steering box and use 90 oil, no kingpin play or play in joints, and u will be amazed how well a Bradford drives...the old concept "a bradford wanders down the road" is rubbish.
And the mechanical brakes work as well if not better than most modern cars...just have to press a little harder under unexpected braking.

In the longer term perhaps I should sell the Javelin and buy a Bradford(?)

Ahhh theres a man coming to his senses