Posted From: 188.8.131.52
|Posted on Thursday, 10 July, 2014 - 07:04 am: |
I have often wondered if mazola or similar could be used as hydraulic oil in situations where leakage would be a environmental disaster
A guy in Bristol put cooking oil in his brakes he got stopped by the police who found his brakes had failed and the fluid had jellied
He was prosecuted and fined
(Message approved by david_gore)
Post Number: 881
|Posted on Thursday, 10 July, 2014 - 09:53 am: |
There are a number of vegetable based hydraulic fluids. Texaco used to market Biostar, which was rapeseed based. I believe it's been discontinued. However, a company in Michigan called Hydro Safe is now marketing another rapeseed (canola) based product.
It must be something that's added (or not added) to the food-use version that makes it gel.
Post Number: 50
|Posted on Thursday, 10 July, 2014 - 09:46 pm: |
Absolutely forget about rapseed-based hydraulic oils. When getting hot they produce charred deposits everywhere in the hydraulic system. I know of a 40 ton Caterpillar bulldozer filled with that stuff needing the whole hydraulic system to be dismantled and cleaned out at costs of over $200'000.
You can get excellent biodegradeable hydraulic oils on ester base, developed over 30 years ago by the small Swiss oil company Panolin.
Post Number: 111
|Posted on Friday, 11 July, 2014 - 12:44 am: |
All this discussion about alternative fluids amuses me. Why don't people just use the fluids they're supposed to use?
If the original fluid is no longer available or costs a fortune then fair enough. Fortunately, RR363 is still available at reasonable cost while enough of us are buying it. But if people start cobbling together their own home-brew brake fluids there will come a time when Castrol raise the price of RR363 to an astronomical level, or will cease to make it at all. Then we will all be in trouble, or we will have to rely on unproven alternatives from dodgy suppliers.
It's not as if brake fluid was used by the gallon. It only needs to be topped up very occasionally and renewed every few years. When factored into the general cost of maintenance, the cost is negligible; and worth paying if it means that the genuine article remains available at a reasonable price.
I think we should all be grateful that a major manufacturer like Castrol is still producing RR363 for a reasonable price, and we should do all we can to encourage them.
Post Number: 438
|Posted on Friday, 11 July, 2014 - 01:40 am: |
I am curious at what price you would go over to the dot3/castor oil mix. Here in the US it retails at $30 per litre. I personally use RR363 but fully understand owners who prefer to use the substitute. I do agree with your argument that buying RR363 keeps the supply available from Castrol, which is one of the reasons I stay with it. $50 per litre and I would probably make my own "homebrew". What about you Bob - how much are you paying for it at the moment and at what price would you start looking at alternatives? Just curious.
Post Number: 120
|Posted on Friday, 11 July, 2014 - 03:55 am: |
Brake fluid is hygroscopic, not by accident. The thinking is that water in the brake line is bad because it can freeze, blocking the line, and it can boil, causing steam effectively evacuating the line. Now, how water gets in there is beyond me, but the pedantic engineer thinking is, "Let's assume that there is water where we don't want it..." and this was intended to mitigate brake failures due to ice or steam. So the thing we warn each other about and view as a nuisance is actually intentional with the ironic unintended consequence of actually attracting water to the brake system. I read it on the internet, so it must be true! :-)
As an aside, with our brake system, I don't think the steam problem even applys, since the return path is different from the supply path meaning steam will evacuate the return path, which has no impact on the effectiveness of braking. Or am I confused about the design?
I think what this means is that there is no good reason to substitute brake fluid and probably a lot of good reasons not to. If brake fluid is an environmental hazard, then it needs to stay out of that environment and a good way to do that is to stay in the brake lines! Old cars are a challenge because, among other reasons, they leak. We fix the leaks or suffer the consequences.
I use homebrew DOT 3/Castor Oil, but I don't have enough time to give any recommendation one way or the other. I do know from my experiments that it separates, but I can't give a good estimate of the rate of separation. The density of DOT 3 is slightly greater than castor oil, so the castor oil will separate and float on top. I only notice this in the lab in the glass containers I have sitting on the shelf soaking various materials for o-rings to see what happens to them; I do not notice this in the brake fluid reservoir sight glass, but this may be a consequence of the design of the sight glass, which draws from one specific level in the reservoir, or it may be that the pump re-circulation is sufficient to preserve the mixture. I don't know the answers to these questions. I have been considering a brake fluid reservoir modification to change the low pressure return from the accumulator to the top of the reservoir, rather than its current comfortable location at the bottom. A small tube should be sufficient... Maybe something with an impeller?
I haven't done it yet because it may not be necessary or it may not be effective, and I have lots of other more important projects, like rebuilding the A6 and getting my A/C working, which in Sacramento is a very high priority indeed. When I do this, I will probably remove the brake fluid reservoir again to give myself room to address a leak in the valve cover gasket at the same time and I will carefully observe the contents to determine if there has been any separation. Stay tuned...
I would add an emulsifier, if I knew what to add that would not impair the viscosity... Any suggestions? (-:
Post Number: 883
|Posted on Friday, 11 July, 2014 - 06:42 am: |
I don't know why your YAK363 (90/10 DOT3/Castor Oil) is separating at all, as mine never has, and I still have my original samples that have been through multiple winters and summers.
It may have something to do with the exact brand of DOT3 you're using. DOT3 is a specification, not a formulation, and while the various brands are substantially the same it's the little things that are probably causing the slight degree of separation you're seeing.
Brian, who admits to using YAK363 now and makes no apologies for that
Post Number: 126
|Posted on Friday, 11 July, 2014 - 06:50 am: |
These are samples I have sitting around that I watch, but are not exactly formulated. It is entirely possible that I exceeded the solution capability of the castor oil in the brake fluid (assuming that they are not mutually miscible) and I am seeing the castor oil equivalent of putting too much sugar on your cereal; it won't all dissolve. I have been much more precise when mixing for "production" and I keep it at the 10% range quite closely.
I didn't give it too much thought, and now with your report that you don't see any separation, I am greatly relieved, because that was the only downside I could foresee.
Thanks for the help,
Posted From: 184.108.40.206
|Posted on Friday, 11 July, 2014 - 06:31 am: |
The jelly in the brakes is a BBC news item
I posted it as a warning
There is no castor oil in brake oil
Castor oil is not that good a lubricant and adding it to brake fluid will not improve the oilyness of dot
Thicker oil doesn't oil better than thinner oil
Castor has been used for race engines in the past where the oil is changed every race
Now no one uses it because much better is available
The race guys change all fluids every race so oils are never used long enough to find how they last
I suspect that castor may break down at 2500 psi and 150 centigrade and turn into something else
All dot oils are cycle tested many times by regulation
Note there is no regulation of LHM}
(Message approved by david_gore)
Post Number: 885
|Posted on Friday, 11 July, 2014 - 12:50 pm: |
But there is castor oil in RR363 and is clearly listed in the safety data sheet.
As far as I can tell RR363 is a Castrol DOT3 (if memory serves, it's also DOT4 compliant as well) fluid with ethoxylated, propoxylated castor oil added as an additional lubricant.
The "ethoxylated, propoxylated" part appears to be related to shelf life and miscibility during very long term storage.
I don't know what Castrol may or may not be using in RR363 besides castor oil, but there's nothing else in the safety data sheets to indicate they've formulated the base fluid any differently than their typical DOT3.
I've already been running YAK363 long enough to know that heat and pressure aren't affecting the castor oil in any visible way. Since the stuff is still used as the lubricant of choice in model aircraft where the engines are running under far more stressful conditions than our braking systems it's not likely to be a problem.
I hope that the others who have been running YAK363/OMAR363 other than myself will chime in (again) with what their ongoing experiences have been. At least two of our regulars (and a couple of semi-regulars) other than myself have been doing so for five years or more.
It was also interesting to see that we may have yet another "RR363 Outage" if the H.D. Rogers/Classic Auto Spares website update just posted is accurate.
Post Number: 112
|Posted on Friday, 11 July, 2014 - 04:19 pm: |
"What about you Bob - how much are you paying for it at the moment and at what price would you start looking at alternatives? Just curious."
It's available from Opie Oils for £14.71 ($25) or FS for £24.25 ($41). It probably costs twice as much from Bentley! The Opie price is quite cheap, and it's not worth looking for alternatives. I don't know at what point I would start looking for allternatives, but it would be over £50. If a bottle lasts me 3 years, that's only £16 a year. Not much to pay for a safe braking system.
Omar M. Shams
Post Number: 416
|Posted on Saturday, 12 July, 2014 - 12:19 am: |
Brian and I have been using the YAK363 formula for many years now. I think I am up to 5 years now on 3 cars. The stuff works like a dream in my application ( hot country).
Posted From: 220.127.116.11
|Posted on Saturday, 12 July, 2014 - 08:11 am: |
Since I posted about castor oil I have found my UK gov oil info sheet
Castor oil is present in most brake fluids
Castor oil leaves a gummy deposit which if excessive quantities can block small holes and similar
In sleeve valve engines this is beneficial and seals the sleeves
The gum is easily removed by flushing or manually. Strip down and wipe
I have changed my mind because I also spoke to a Citroen guy who suggested Castrol R 15% dot 3 4 5.1 for DS and 10% for ID manual steering or Dot 5 silicon for show cars or no fluid at all and seal tank off. He also uses RR363
Lhm cars he only uses LHM however aero red oil can be used but why bother change 2 years not so much miles but time dependent
I have got some castor oil and dot and a epdm edpm seal in a jam jar
and I will check
The seal is 10.003 mm wide and with 1/2 kilo preassure
I don't really know what I am doing but will figure it out as time passes
(Message approved by david_gore)