John Morrison Posted July 16, 2005 Report Share Posted July 16, 2005 I'm in the process of stripping out the 4 engine bay to totally re-paint. The clutch and brake master cylinder bracket is in the usual state, all crud and old spilled brake fluid. Does any one manufacture a stainless steel replacement? or do I just re-furbish and try to take care when ever I bleed anything? John. Quote Link to post Share on other sites
MikeF Posted July 17, 2005 Report Share Posted July 17, 2005 Why not use silicone fluid? This behaves more like oil with respect to paint, so you get a small wipe off puddle instead of a blistery repaint job Quote Link to post Share on other sites
John Morrison Posted July 17, 2005 Author Report Share Posted July 17, 2005 Thanks Mike, Thought about silicone but I did not want to do all the brakes, wheel cylinders etc., now, and I think you need to go that way to do the job properly. Can still go down the silicone road sometime and have a ss bracket as well. john Quote Link to post Share on other sites
Guest GDalzell Posted July 25, 2005 Report Share Posted July 25, 2005 Careful with thr silicone. I has some good adivce at Malvern. Evidently it is thicker than DOT 4 and this stops the brakes releasing quite so quickly. cheers, Graham Quote Link to post Share on other sites
jonlar Posted July 25, 2005 Report Share Posted July 25, 2005 Hi Graham, John and Mike, I have to say I've used silicone fluid since 1984/5ish in Land Rovers and all sorts, I've never had a problems with rust in the steel parts, never had brakes sticking on, which I have had on some motors with glycol/mineral brake fluids which is hygroscopic - takes up moisture over time, hence why it needs to be changed on a regular basis. I know that it's said you should change all seals, but I never have and not had problems. What I have done is been careful not to give air any chance to get into the fluid (pour silicone into a jug, cover with cling film and allow to stand overnight for any air bubbles to rise, and then keep master cylinders topped up very gently to avoid introducing bubbles. What I've always done is to remove old brake fluid from master reservoir using a syringe (plastic food oil basters are good), open rear N/S brake bleed valve and introduce silicone to master cylinder and allow gravity to bring silicone through to nipple over several hours, then thoroughly bleed RNS, ROS, FNS, FOS (furthest to nearest to master - would it be reverse the sides on LHD cars?), sling ½ a cupful or so, from each point to make sure the whole system is thoroughly flushed through. Quote Link to post Share on other sites
tony13579 Posted July 28, 2005 Report Share Posted July 28, 2005 I have had my brake bracket powder coated, it looks great but I dont know wether that is brake fluid proof! you could also get it chromed... also note that 2006 compliant paint is going to be 2 pack or water based, not cellulose. I dont know how these react with brake fluid. If you want to be able to get touch-ups done I suggest you look at 2006 compliant paint with a spare 1 litre can. All the people I talked to hated sillicon fluid. If you have a brake problem it will take a day to get back on the road. Quote Link to post Share on other sites
Mychael Posted July 28, 2005 Report Share Posted July 28, 2005 Replacing conventional brake fluid every 12 months overcomes the moisture absorbtion issue. I realise this does Not answer your question about the paint. Why not try an engineering shop to see if they could fold you one out of Stainless steel. Mychael Quote Link to post Share on other sites
John Morrison Posted July 28, 2005 Author Report Share Posted July 28, 2005 Thanks Guys, question was prompted by a mate aquiring a 6 clutch master cylinder bracket in ss. Tried a fabricators, but he didn't really want to know so quoted me daft money. I will just clean up and spray Black, and be careful. john. Quote Link to post Share on other sites
jonlar Posted July 29, 2005 Report Share Posted July 29, 2005 All the people I talked to hated sillicon fluid. If you have a brake problem it will take a day to get back on the road. Hi Tony, I've got to ask what on earth is being referred to - total b******s in my experiences since 1980 ish, in a wide variety of vehicles. If it was half as bad as you make out, it would've gone off the market years ago! No-one would've bought it. Quote Link to post Share on other sites
Don Elliott Posted July 31, 2005 Report Share Posted July 31, 2005 I've used silicone fluid in my TR3A clutch and brake systems since 1990 and more than 84,000 miles of trouble-free touring. At that time I replaced all the seals and rubber hoses in the system. To top it up, it has to be poured in gently. You don't want to just pour it in as this will make bubbles which will take time to "float" out. I have never drained the system and while the purple fluid has turned black, it still works fine. Note that in a TR6, the same purple colour for the fluid will turn clear. It is thought that this is caused by the sun getting into the fluid through the translucent plastic reservoir. Don Elliott, 1958 TR3A Quote Link to post Share on other sites
jonlar Posted July 31, 2005 Report Share Posted July 31, 2005 Hi Don and thank you, I was beginning to wonder what I'd been doing wrong all these years! Quote Link to post Share on other sites
graeme Posted July 31, 2005 Report Share Posted July 31, 2005 Jon, You are not alone, I have also used Silicone fluid in my TR4A since 2001 with no problems at all. Surprisingly, the liquid has turned from purple to clear, so that blows Don's theory! Graeme Quote Link to post Share on other sites
BrianC Posted August 1, 2005 Report Share Posted August 1, 2005 Slightly off the original topic but closely related (because I was also considering the possibility of a stainless steel bracket): Assuming all the hoses, cylinders and/or seals are known to have been replaced on a car, how can one tell whether it has been filled with conventional or silicon brake fluid? Since colour appears not to be a reliable indicator, is there any obvious difference in feel (e.g. slipperiness) or smell? Other than contacting the previous owner, the only option would appear to be to smear a small sample on a suitably painted test piece and see what the damage is. Has anyone got any more scientific suggestions? Quote Link to post Share on other sites
jonlar Posted August 1, 2005 Report Share Posted August 1, 2005 Hi Brian, can't answer your question off the top of my head, but will try a little experiment tomorrow and come back tomorrow night! Quote Link to post Share on other sites
Don Elliott Posted August 2, 2005 Report Share Posted August 2, 2005 My silicone fluid is purple when new. After a time in my TR3A, it turns black. If I'm bleeding the clutch line, I collect the black fluid. Then I let it sit for about a week in a clean jam jar and the black bits settle to the bottom. The rest of the fluid is still purple telling me that it is silicone fluid. If your fluid is clear as in the TR6's, this method wouldn't be of any use to you. But if it has turned black, give it a try. Don Elliott, 1958 TR3A, Montreal, Canada Quote Link to post Share on other sites
jonlar Posted August 2, 2005 Report Share Posted August 2, 2005 Sorry Brian, didn't get the chance today to try - putting some silicone in a test tube with a couple of drops of water, shake and see if water settles out, and do the same with some mineral fluid. This won't help you know if silicone has been used before, only the PO could tell you that. As I said above somewhere, I've never changed seals when changing fluids, but just taken great care to extract as much of the old fluid and flush with replacing silicone. To date without any problems - maybe I've just been lucky? - and I'll do the same in future. Quote Link to post Share on other sites
jonlar Posted August 4, 2005 Report Share Posted August 4, 2005 Hi Brian and all, I've done this little experiment as scientifically as possible, with my wife adjudicating (she didn't know which fluid was which). Using 7ml Vacutainers (glass tubes which are evacuated of air for blood and fluid samples - medical and veterinary use - I'm only on Prescription drugs, but when this "nanny state" government of ours does away with Co-proxamol - as the result of David Kelly's "suicide", I honestly don't know what I'll do for pain relief, but that's as they say another story) and 20g needles, I drew up 6 ml of each fluid at my timber garage ambient temperature of 83ºF, the time taken for each type of fluid was within 1/10 sec of each other, both taking 10.5 secs, fairly reasonable evidence of very similar viscosity. Both tubes were then opened and excess 5 ml emptied from each, leaving 2ml, to which I added 2 ml of tap-water. Both tops were replaced and tubes vigorously shaken, the one containing silicone fluid actually dropped off, when held by the plastic top, whereas the mineral fluid one had to be pulled off - did this indicate better lubrication by the silicone - I'm not certain without pursuing this further. Within 2 minutes, the silicone fluid was separating out from the water (I'm not sure which has risen to the top yet - I'm leaving for a few days before opening again to ascertain which, I think the silcone has risen from the appearance of the meniscus at the meeting of the water and silicone), but the mineral fluid is as mixed as ever, air bubbles seemed to surface and disappear at equal speeds. You pays your money and takes your choice, but this is conclusive to my mind, something which is very evident though and that is water will not mix with silicone fluid, I know where my choice remains. Performance at racing temperatures I've got NO idea about and will leave to others more knowledgable and practised than me. The answer to your question Brian (sorry for the delay) is that you have to ask PO if seals have been changed or check servicing records, or withdraw a couple of mls of fluid and mix with water, if it mixes it's mineral, if it doesn't it's silicone, I'll probably get my wrist slapped by someone (anyone H&S trained....) for suggesting this, but stick your finger in the fluid, if it washes off easily with water it's mineral or glycol based, if your skin stays oily and water runs off it's silicone, water and silicone hate each other and will not mix. I've found if I've spilt fully synthetic engine oil on skin, it remains water-proof for hours - what's that all about........? Quote Link to post Share on other sites
BrianC Posted August 4, 2005 Report Share Posted August 4, 2005 Thanks for the report on a thorough and fairly conclusive experiment. The tests should be simple enough (even for a GCE O-level Chemistry Grade 9 failure like me!) and probably more reliable than relying on the colour. I will try on a couple of family cars at the weekend. Quote Link to post Share on other sites
BrianC Posted August 18, 2005 Report Share Posted August 18, 2005 Just in case you thought I'd chickened out, I did try the "finger-test" on the family cars. However, the results are not totally conclusive, as in all cases the fluid washed off easily (and also appeared clear, rather than purple or black). Given that only one of these was believed/suspected to have silicone, I guess it probably doesn't. Since I can't afford to syphon off a decent sample to test properly, as per jonlar's method, and I have no suitable equipment (my wife will confirm this!) I will either have to beg, borrow or steal a kid's chemistry set or wait until I need to change or top-up the fluid in this car. Quote Link to post Share on other sites
BrianC Posted September 1, 2005 Report Share Posted September 1, 2005 Quote (jonlar @ Aug. 18 2005,21:01) Hi Brian, you literally need only a couple of drops of fluid in clear container (you might even get away with a disposable plastic spoon), with a couple of drops of water, if it mixes it's mineral base. Re. the samples I did, the mineral fluid hasn't separated at all. The silicone is unmistakeable! Hope this helps. Regards, CoastGuardJon Jon, Thanks for the PM (sorry I have responded sooner but I have only just discovered it). I did, in fact, do exactly as you have suggested and used a transparent plastic spoon with a very small sample. As soon as water was added to the standard brake fluid it turned milky (like adding water or ice to Pernod or Ouzo, but probably less tasty) and still hasn't cleared several days later. I then revisited the suspected silicone fluid and noticed that when viewed under good lighting (or with a torch) it did appear in the master cylinder reservoir to be purple. When I added water to a half-teaspoon sample it did not mix. Even vigourous stirring just left lots of separate globules of brake fluid, with no sign of mixing with the water. All of which is a long-winded way of saying that your simple test for determining whether you have conventional or silicone brake fluid is highly successful and requires no special tools. I will update the original forum thread and try to put a separate link to it for others who have the same problem. I have asked a number of people the same question so I'm sure it deserves wider exposure. Many thanks for the help. Returning to to original subject of this thread, which I inadvertently highjacked: Would chrome or nickel plating of the original bracket be feasible (and cost-effective) as an alternative to stainless steel? Quote Link to post Share on other sites
jonlar Posted September 1, 2005 Report Share Posted September 1, 2005 As the result of seeing Brian's post, I've just checked the sample tubes, still no mixing of silicone with water, and no separation at all of the mineral BF/water. Quote Link to post Share on other sites
Mychael Posted September 1, 2005 Report Share Posted September 1, 2005 Brian C, I believe cadmium plating is the best for corrosian resistance but few places will do it due the health and safety aspect so I'm assuming it would be most expensive. You see cad. plating on aviation stuff like bolts. On another tack I asked a brake bloke about swapping to synthetic/silicon brake fluid, his reply was he avoids it on older cars as it's a hassle to bleed etc. I cannot comment, I've never tried it. Mychael Quote Link to post Share on other sites
jonlar Posted September 2, 2005 Report Share Posted September 2, 2005 Just a thought Brian, there was mention recently of a company that supply exchange calipers which are cleaned and plated as part of the re-con, these look very good, might be worth trying them for plating...........? Quote Link to post Share on other sites
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