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Which brake fluid

PostPosted: Thu Apr 19, 2012 7:30 am
by jono
Time to fill up my braking system for thsi first time - calipers all rebuilt by Classic Car Automotive, new master cylinder etc (servo removed).

What is the current wisdom on brake fluid - can someone simply tell me what I should buy and how much of it :?:

Many thanks

Jon

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 8:01 am
by garyeanderson
Some reading for you with someone elses opinion

http://www.buckeyetriumphs.org/technica ... /Fluid.htm

Maybe a liter of Castrol LMA will get you going if you have trouble bleeding the system, if not a 12oz can will do it but you'd be lucky, better get a couple of 12oz.

Gary

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 8:07 am
by elansprint71
If the whole system has been replaced- pipes etc, you would be best buying plenty of fluid, it's not expensive; reason for this is it will take ages to get all the tiny bubbles out of the system. I think I bled mine six times when everything was changed and then again after six months.

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 8:33 am
by jono
Just called Classic Car Auto:

"any good DOT 4" "NO don't use silicone, it's rubbish you'll have nowt but trouble"

That's good enough for me.

Jon

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 8:37 am
by UAB807F
I'd agree with Pete, brake fluid is cheap enough compared with what you've already spent on parts.

I tend to buy the biggest container that halfords do, I'd guess it's 4L. Way too much but I know that I can renew brake & clutch completely, bleed, test drive & then bleed again without worrying if I'm going to run out. It sounds crazy I know but the nearest motor factor is 10 miles away from us and when you factor in the hassle of driving there twice, petrol, etc, and it's just not worth the chance of running short.

I always end up with some left which I generally seal as best as I can to keep out air and use in the clutch system or for the odd "emergency". Write the date on the can and chuck it away when it's past it's sell-by date ? 2yrs ?

Brian

ps - read your post while composing this, I just buy dot 4 as well.

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 8:56 am
by oldelanman
jono wrote:Just called Classic Car Auto:

"any good DOT 4" "NO don't use silicone, it's rubbish you'll have nowt but trouble"

That's good enough for me.

Jon


Not Classic Car but it seems that there's a consensus on that.......


Servo warning 001.jpg and


I agree with the others - buy plenty it's cheap enough -I bought a litre initially and it wasn't nearly enough.

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 9:37 am
by Robbie693
I never seem to learn - I always buy the middle size and end up going back for more :roll:

One thing I found last time though - Halfords are a rip-off! I bought twice the amount (DOT4 Mintex brand) for less than half the price at a local motor spares place...

Robbie

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 9:52 am
by bcmc33
jono wrote:Time to fill up my braking system for thsi first time - calipers all rebuilt by Classic Car Automotive, new master cylinder etc (servo removed).

What is the current wisdom on brake fluid - can someone simply tell me what I should buy and how much of it :?:

Jon,

This is something I saved from this forum some time ago - written by someone that knows.
Brake Fluid Information.doc
(73.5 KiB) Downloaded 628 times

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 9:53 am
by Baggy2
Ive been using Silicon in my elan and other Classics for more years than I care to remember. Since doing so I have never had any problem and in particular Ive never had pistons seize due to rust even after long periods where the car has not been used. of course you pays your money and takes your choice but I would be interested to know why silicon gets the big thumbs down.
All the best
Baggy

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 7:05 pm
by Galwaylotus
Baggy2 wrote:Ive been using Silicon in my elan and other Classics for more years than I care to remember. Since doing so I have never had any problem and in particular Ive never had pistons seize due to rust even after long periods where the car has not been used. of course you pays your money and takes your choice but I would be interested to know why silicon gets the big thumbs down.
All the best
Baggy

One reason is that it is more compressible than DOT 3 or DOT 4 (or for that matter DOT 5.1). It seemed to be all the rage in the '70s for a while until the racers discovered that characteristic. If silicone fluid was better, it would be original fitment by manufacturers.
I buy 500ml containers of Ferodo DOT 4 (recent cost ?5 each) as it's readily available in my motor factor's so there's never much waste and the container stays "factory sealed" until I need it. 8)

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 8:39 pm
by alexblack13
Baggy2 wrote:Ive been using Silicon in my elan and other Classics for more years than I care to remember. Since doing so I have never had any problem and in particular Ive never had pistons seize due to rust even after long periods where the car has not been used. of course you pays your money and takes your choice but I would be interested to know why silicon gets the big thumbs down.
All the best
Baggy



Me too guys... I like it in the clutch too because of the heat issue. I have re routed the pipe away from the exhaust and fitted a stainless flexy pipe up to the master. But absolutely no issues at all. Even during that heat wave we endured at le mans 2010.. That was bloody hot that was... Never missed a beat.. (I am whispering in case it hears me talking about it).. :roll:

Brakes are good and a nice firm pedal.. I will be changing it this summer before it starts getting used for real..

AB.....

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 8:41 pm
by alexblack13
OOPs by mistake... removed... :roll:
ab

Re: Which brake fluid

PostPosted: Thu Apr 19, 2012 10:22 pm
by Baggy2
One reason is that it is more compressible than DOT 3 or DOT 4

For general road use does this really matter?

If silicone fluid was better, it would be original fitment by manufacturers.

I guess the higher cost might be an influence?

Re: Which brake fluid

PostPosted: Fri Apr 20, 2012 8:53 am
by Chancer
All my race cars used silicone fluid, I never noticed it being any more spongy in extreme conditions than glycol fluids.

The only thing that ever happened was the rear calipers on a Caterham 7 would get very hot with heat soak in the paddock between sessions as the caliper was at the top, this was aggravated if the handbrake was inadvertantly used, in that instance you would have a very long pedal until after doing a few dabs during the out lap or parade lap, this also afflicted those using traditional brake fluids.

For me the absence of corrosion and no moisture take up would make me choose it every time.

Re: Which brake fluid

PostPosted: Fri Apr 20, 2012 12:08 pm
by elanmac
I have used silicone brake fluid for the last 12 years in my Elan and before that in my mk1 sprites. never had a problem. The reason silicone fluid is in not used by the manufacturers is probably due to the loss of revenue with fluid changes every two years. A similar thing was with vacuum cleaners needing new dust bags, their was no effort to make cleaners bagless until Dyson showed the way. Now most vacuum cleaners are bagless using old technology.
Mac