CH12/LHS2/RR363 substitute

CH12/LHS2/RR363 substitute

Posted in the Rolls-Royce Forum

First Prev
of 2
Next Last
Jan Forrest

Bradford, UK

#1 Aug 29, 2007
For those who run earlier models needing vegetable/synthetic hydraulic fluid this page ...

http://www.candokaraoke.com/fluid.html

... may pique your curiosity.
Many have expressed concerns that RR363 is not 'made like it used to be'- perhaps due to the substitution of the original castor oil with a synthetic substitute.
As the basic design of the Rolls Royce hydraulic system is virtually identical to the one fitted to early Citroen DS/ID models it is reasonable to assume that the same fluid should be used in any varient of it.
The author of the site has concluded that a ratio of 9-10% of castor oil in otherwise pure DOT4 hydraulic fluid will give an identical viscosity to the original CH12/LHS2/RR363 with no known adverse reactions. Admittedly some Australian enthusiasts have gone as high as 15-18% castor oil with similar results although it has been noted that this quantity might be too high in many countries if the ambient temperature drops below freezing, when 'clumping' of the castor oil has been observed.
So far I've obtained 5 litres of DOT4 and I'm waiting for delivery of the 500ml of castor oil to mix into it. Once done, and time permitting, I shall flush through the hydraulic system of my Shadow 1 and replace all the old fluid with the new mix. Then after a few hundred miles I shall report back with my observations.
Omar Shams

UAE

#2 Jun 12, 2008
I have read the notes with interest. It has been a year since the above posting, and I am dying to know if the experiment has worked. Shall I swap the RR363 in my Wraiths to Dot4 and 15% Castor oil? I have already bought the castor oil.......... waiting to hear form someone please
Allan Maclean

Casuarina, Australia

#3 Mar 4, 2009
I have 1970 shadow and have noticed a very significant improvement in overall terms.This is due to the addition pure caster oil to dot 4 penrite.
Jan Forrest

Bristol, UK

#4 Mar 17, 2009
"I have read the notes with interest. It has been a year since the above posting, and I am dying to know if the experiment has worked. Shall I swap the RR363 in my Wraiths to Dot4 and 15% Castor oil? I have already bought the castor oil.......... waiting to hear form someone please "

The percentage of castor oil depends on ambient temperatures the car experiences. In any part of the world where the temperature dips below 5C that should not exceed 10%. There is little advantage to using more unless you already change the fluid twice per year: Before and after Winter.

NB: The fluid should be changed at least EVERY 2 years. More often in humid climates as it is strongly hygroscopic.

Unfortunately shortly after my original post I had a ... difference of opinion ... with the UK Revenue & Customs and the car has been stood for a full year without the opportunity to do any work on it. Luckily it is due for return this Friday when I shall be bleeding the whole system plus doing a few other jobs to recommission it for the road after its long sleep.
One important note! This susbstitute MUST NOT be used in any car with a system meant to be used with LHM (mineral fluid). There should be notices on the top of the reservoir to this effect. Ignore these warnings and the whole system - brakes and suspension - will require new seals and rubber hoses in a matter of weeks! The same goes for RR363 cars which are refilled with LHM.
Allan Maclean warrnambool

Kangaroo Point, Australia

#5 Oct 14, 2009
I also have a 1970 shadow and have added 2% of castor oil penrite dot 4 fluid. Changes noticed over a period of some 12 months add up to a better car in overall terms.Including the steering and cornering.

Since: Oct 09

Kallangur, Australia

#6 Mar 3, 2010
I have increased the original 2% of caster to 5% and there is a marked improvement in performace. Engine sound is a low level hum. Will do a full check on all lines at the end of the year.
Jan Forrest

Wakefield, UK

#7 Mar 18, 2010
Despite The Old Girl being stood on a windswept, gale lashed quayside for a full year the CO/DOT4 mix was as good as when it went in. Since then I've since completely overhauled the calipers and bled the hydraulic system. There was little difference between the old stuff that came out and the new that went in. That was nearly a year ago and, despite the long,cold winter we've had in Blighty (at least compared to the last couple of decades) the fluid as observed in the level windows is still 'sweet'.
According to the 'experts' on the Australian RR website you should use something called 'propoxylated ethylated castor oil rather than the BP or edible stuff due to it staying miscible with the DOT4 for longer - allegedly. I couldn't say.
Shadow 11

Ireland

#8 May 19, 2010
I've just flushed and changed the RR363 and bled the system. the car is driving well but I have noticed that the resevoir temperature is fairly warm, i.e., not quite boiling but noticeably warm to the touch. Is this normal or is there an underlying cause?
Jan Forrest

Wakefield, UK

#9 May 22, 2010
Check all the brake calipers to ensure that none of the pistons are not being pushed back and therefore binding on the disc.
david haynes---- wantage

Oxford, UK

#11 May 23, 2011
I'm investigating a substitute for RR363 and read the articles on this page-----in your opinion do they still hold good bearing in mind we have had some very cold winters.i hav a Shadow !
Jan Forrest wrote:
Despite The Old Girl being stood on a windswept, gale lashed quayside for a full year the CO/DOT4 mix was as good as when it went in. Since then I've since completely overhauled the calipers and bled the hydraulic system. There was little difference between the old stuff that came out and the new that went in. That was nearly a year ago and, despite the long,cold winter we've had in Blighty (at least compared to the last couple of decades) the fluid as observed in the level windows is still 'sweet'.
According to the 'experts' on the Australian RR website you should use something called 'propoxylated ethylated castor oil rather than the BP or edible stuff due to it staying miscible with the DOT4 for longer - allegedly. I couldn't say.
Jan Forrest

Rotherham, UK

#12 May 23, 2011
It's been over a year since I changed the hydraulic fluid in The Old Girl and she still rides and handles as well as she did the day I did it. How much better she might ride with the propoxylated ethylated castor oil rather than BP (edible) castor oil in the mix is open to debate. However I believe that as it's an industrial chemical it can only be purchased in multiples of 5 litres which is far more than you could use in a single car before it 'went off'.
david haynes---- wantage

Oxford, UK

#13 May 23, 2011
i think the total system takes about 2.5 litres and so the quantity of propo/ethyl will be very small------perhaps there is a way to preserve it for future use-----presumably it would have to exclude air----surely that is not impossible-----a couple of things cross my mind as i write---1. fill up a container till no air will be left. 2. what about a wine gadget for excluding air (a pump)
Jan Forrest wrote:
It's been over a year since I changed the hydraulic fluid in The Old Girl and she still rides and handles as well as she did the day I did it. How much better she might ride with the propoxylated ethylated castor oil rather than BP (edible) castor oil in the mix is open to debate. However I believe that as it's an industrial chemical it can only be purchased in multiples of 5 litres which is far more than you could use in a single car before it 'went off'.
hendrix62

Tel Aviv, Israel

#14 Oct 2, 2012
hi,
1.i own silver shdow 76 lwb....i live in israel and here they dont sell the rr363,can someone tell me is there substitute oil that i can use?
2.if i want to change the oil bymyself how do i do that?
many thanks
Shadow 11

Ireland

#15 Oct 2, 2012
Jan Forrest wrote:
Check all the brake calipers to ensure that none of the pistons are not being pushed back and therefore binding on the disc.
Thanks Jan. Opinion appreciated. You may be on the right track. I noticed that the front nearside wheel becomes very warm after a long run. I've bought new caliper pistons and seals so I'll replace them soon while I'm doing the next hydraulic flush.
Jan Forrest

Rotherham, UK

#16 Oct 3, 2012
hendrix62 wrote:
hi,
1.i own silver shdow 76 lwb....i live in israel and here they dont sell the rr363,can someone tell me is there substitute oil that i can use?
2.if i want to change the oil bymyself how do i do that?
many thanks
1) If you check the dates above you will see that it has been over 3 years since I flushed and refilled the hydraulic systems on my Shadow with the RR363 substitute. Although I should have done the job again last year the fluid is still going strong with no signs of excessive moisture absorbtion. Neither the braking or ride quality have deteriorated, so in my opinion there is no real reason to try and import the pukka RR363 in favour of the home made stuff.

2) Bleeding the system is little different to any other car. The main difference is that the engine MUST be running for it to work. If not there will be no pressure in the system as the later Shadow models don't have a brake master cylinder. Another important point is that all the calipers have to be done in the correct order as laid out in the official RR manual
http://rrtechnical.info/sy/04_sy
Note that the last of the Shadow 1 models are more like the early Shadow 2 due to the 'quiet updates' that were incorporated into the design during the late 70's.

If you have access to high pressure equipment it's good practice to check that the gas pressure in the front accumulators is still within bounds. By high pressure I mean at least 1,000 psi (68BAR) as that is the pressure of nitrogen gas that should be in there. Don't worry about the recomendation that the gas should be pure nitrogen as a standard 'dry breathing mix' as used in SCUBA gear will do just as well.

Fortunately the rear suspension is a recirculating one so that there will be little contamination between the old and new fluids if you simply empty, clean and refill the relevent reservoir. However all you have to do is partially refill it (about 1 litre), run the engine with the rear doors open and load/unload the boot with some heavy weights a couple of times to activate the self levelling. This should get most of the old stuff into the reservoir where it can be removed and replaced with fresh fluid. While we're on the subject: The correct ride height for the rear of a Shadow is such that you should be just able to slide a flat hand under the rear wheel arch and onto the top of they tyre with the system UNpressurised. If you can't then the rear springs may need replacing. A cheaper alternative is to obtain 2 sets of 'spring assistors' of the hard rubber ring type and place one of each both above and below the existing spring. Several fellow members of the Australian RR forum have tried this since I recomended it and reported that the ride quality has returned to normal.

Don't forget to check the condition of all the flexy hoses as they will be coming to the end of their useful life by now if they are original factory equipment - assuming that they haven't been replaced already. Also the components in the 'rat trap' beneath the car level with the driver's seat may need overhauling. Seals are readily and quite cheaply available from the usual suspects, many of whom are quite happy to ship internationally at reasonable rates.
David

Oakland, CA

#17 Feb 5, 2013
It may be of interest that Der Franzose in Germany has commissioned a batch of LHS2 according to the original Citroen formulation. The product is made by Pentosin and is not available from anyone else AFAIK.
Jan Forrest

Rotherham, UK

#18 Feb 6, 2013
It would appear that there are differences between original formulations of LHS2 and RR363 in that the latter exhibits lower viscosities at all tested temperatures. Whether this has changed in the Pentosin product I couldn't say. Certainly pure DOT 3 or 4 fluid gives a harsher ride in most Shadow 1's and also the very first of the Shadow 2's which the addition of 10% castor oil seems to overcome. Those owners lucky enough to live in areas of the world that never or very rarely see freezing temperatures can increase this to 20%, but the rest of us would have to change the fluid twice annually as that concentration might be too high in the Winter months.
Roger Gill

Montrose, UK

#19 Nov 15, 2013
Allan Maclean wrote:
I have 1970 shadow and have noticed a very significant improvement in overall terms.This is due to the addition pure caster oil to dot 4 penrite.
Hi I have seen your posting on the forum about brake fluids, I have topped up my 1970 shadow with LHM fluid and it appears this is wrong, its beenin some months now, no ill effects but reading these posts maybe I should have RR 363 in, is it easy to bleed all the system brakes shaould be ok at the calipers but what about the rear suspension? I only filled the rear resovior up IE to the right when looking over the wing, does that do the suspension only? thanks for any help
Jan Forrest

Rotherham, UK

#20 Nov 15, 2013
I am quite surprised that the brake seals have stood up to using LHM in an R363 system! This might be that the mineral oil is still floating on top of the veg based DOT fluid without any serious mixing of the two. To avoid any trouble in future you should immediately empty the reservoirs - a turkey baster should suffice. With them completely empty you must now remove anything that can be removed, clean everything with a CLEAN lint-free cloth soaked in a little unleaded petrol and ensure that it is all dry again before reassembly. The procedure is outlined in the 'Hydraulics' section of the workshop manual which is available here

http://rrtechnical.info/sy/04_sy

It might be a good idea to then flush through the whole hydraulic system just in case there has been some mixing. Failure to do so might easily result in a serious overhaul bill in the ££thousands££! Don't forget that seal failure in the calipers would result in partial or even complete brake failure and even more damage to the car - not to mention anything OR ANYONE you hit.
Jan Forrest

Rotherham, UK

#21 Nov 15, 2013
Oops! My mistake. Never use petrol to clean the reservoir components. Methylated spirits ONLY and dry with a compressed air line/blower. If there is any detritus in the bottom then a sheet of ordinary kitchen paper can be used to carefully remove it. Also the rear reservoir serves both the suspension rams and the high pressure brakes. As such the fluid in the suspension side does not usually leave the reservoir unless the height rams are activated by significant weight in the rear of the car or by the rear springs having settled over time. Unfortunately this part of the system is circulating so it's essential that you bleed both the self-levelling and brake circuits.
As I put before; a rough & ready, but reasonably accurate, method for checking the ride height of the rear of the car is to wait until the system has completely depressurised (overnight or longer) and see if you can slide a flat hand on top of the rear tyre without slicing off your knuckles under the rear wheel arch. If the top of the tyre disappears under the arch then the springs have settled and remedial action will be necessary in the not too distant future. I've tackled that subject in a previous response further up this page.

Tell me when this thread is updated:

Subscribe Now Add to my Tracker
First Prev
of 2
Next Last

Add your comments below

Characters left: 4000

Please note by submitting this form you acknowledge that you have read the Terms of Service and the comment you are posting is in compliance with such terms. Be polite. Inappropriate posts may be removed by the moderator. Send us your feedback.

Rolls-Royce Discussions

Title Updated Last By Comments
brake pressure 1 failure in a rolls royce silve... 16 hr NEWORL 1
1976 silver shadow II (Jul '10) Thu Futility2006 18
rolls royce silver shadow (Feb '07) Aug 3 Matt 69
Poll hlm oil leak spirit 95 Jul '16 Bob 1
Rolls Royce silver shadow ll transmission will ... (Apr '14) Jul '16 carole 26
Temperature knob Jul '16 ameril2013 1
1974 rolls royce starter removal Jun '16 Jimmy from NY 1
More from around the web