Morgan +4 Forum

Awww, Tim, you had to go and challenge my (apparently somewhat mis-remembered) story! Dang. I hate it when I remember stuff wrong. But -- I remember reading the story, and I remember that the term DOT3 was used, so I did some research to see if I could find support for the underlying idea, ie: that a super-high performance race car was using what was humbly labeled as DOT3.

"Ford High Performance Brake Fluid" was a development of the GT40 program in the 1960s. It is still sold today as race fluid with a DOT3 label yet it has a dry boiling point of 500˚F (I included a table of required minimum boiling points below). Whether the Ford fluid being used in the GT40 racing program was actually labeled DOT3 at the time of the events in the story, I do not know (the date of the SAE brake fluid standard J1703 was Sept. 1, 1967, but I can't tell whether that was the original publication date or the date of the first revision). I suppose it could be that writer was referring to it as DOT3 retrospectively, but if not comparing it to DOT4, I have to wonder what would he have been comparing it to. He certainly thought the story remarkable enough to write about it.

I could not find a publication date for the SAE standard regarding DOT4 fluid but I assume it was some time later. The story (at least as the way recall reading it) would have occurred after the introduction of DOT4 but before the introduction of DOT5 or 5.1. For what it's worth, GT40 Mark IVs were still racing in 1969.

FWIW, although I couldn't find the introduction date for the DOT4 standard I do recall my brother (one of the least car-knowledgeable persons I've known, then and now) telling me he didn't want to use DOT3 in his car because it required DOT4 and he worried about damaging the seals. I recall it being in 1973 or 1974, while he was still in college. If my brother was aware of it, I would be surprised to discover it was new news at that time.

I have boiled DOT4 brake fluid in my 2004 VW R32 when I was doing some lapping sessions at the local motorsports academy but the fluid was likely four or five years old at the time and undoubtedly had some moisture in it. Although it was on street tires they were pretty wide and the front brake rotors were huge for a car that size so there was a lot of heat being generated in the front brakes.

I try to bleed race car brakes about once a year and don't wait more than two years to do so in both those and our daily drivers. I don't care for the fact that replacing every bit of fluid in a car with ABS is a much more complicated process than something like a vintage Morgan!

I found some interesting information about performance of various brands -- see attachments.

Duncan

Non-silicone based fluids:

Minimum boiling points Dry Wet

DOT3 (SAE standard J1703) 401˚F 285˚F
DOT4 446˚ 311˚
DOT 5.1 500˚ 356˚
Ford HP fluid (labeled DOT3) 500˚ (>285˚F but <311˚F) https://www.maximummotorsports.com/Ford-High-Performance-Brake-Fluid-P679.aspx

Golly, I'm sorry Duncan. It does make an interesting story. Here's a link to what Carrroll Smith had to say about brake juice. I thought the Ford HD stuff was truck stuff but it had a different origin. This isn't the latest up to datest info as Carroll left us 10-12 years ago but our cars aren' the latest either.

https://www.m3post.com/forums/showthread.php?t=590914

So Bob, have we answered your brake juice question yet?

Tim(D.Y.M.)

Thank you folks

All I wanted to know was what should I top the fluid' until I get a chance to replace the existing

I leant a few things here most importantly that how to test if the existing liquid is synthetic or not and if it isn't.............any non synthetic will do as temporary measure. So for my primitive Morgan I went to Reiley's and spent $4.95 and bought some DOT 3 non synthetic small bottle and after testing the water test just added the stuff and 50 miles later no problems and the car still stops as it should. Which leaves a question ? what was the small pink colour liquid (light oil ) on the floor of my garage? Just thinking about it "much ado about nothing" as it could be the drip of Marvel Mystery Oil when I was lubricating the SU pots because I baffled myself for hours checking all brake pipes and there were no leaks.

I have many manuals for repair of Morgans and nowhere they specify or say anything about the fluid for brakes. While GoMog manual talks about it I did not notice a specific conclusive reference to any specific fluid. I had to come here and as it transpired a very decent discussion came out of my silly question for which I am eternally grateful to all contributors.Now this discussion is here and will remain for posterity for future novice custodians of the old Morgans

As I continue with my learning curve on this Morgan I will post my findings or questions and while they may be trivial if they can ignite such detailed answers it has to be good for the Morgan family

---

I am always OK............. the trouble is with the others :-)

Yes, you ask good questions. These debates are ongoing..you simply stumbled into a major one that has been going on for some time.

GoMoG answers your question, sorta. For the most part, I write articles when my interest, research and personal/related experiences are engaged by a forum debate or inbox question. In the brake fluid case, the article was the result of a long eMog debate 15 years ago. At that time, some of the respected Morgan gurus swore by DOT 5. After all, the US Army was using it! (I understand that they have been pleading with Congress to allow them to stop!)

Some of these people were winning Concours competitors, and, in fact, DOT 5 does NOT burns off car paint, leather and human skin..as the others do. So the article was written with needed diplomacy..aka without candor and fudgy clarity. The main thing I was trying to convey is DO NOT MIX DOT 5 with anything..even trace elements can cause a disaster.

But that has been the case with most GoMoG articles. Automobile lore keeps changing, developing. It is not a stagnant only-one-way art form. There are SO many options for every instance. GoMoG tries to convey as many options as it can and is open for more. So while I know that people want simple answers, simply put..my goal is to convey knowledge rather than instructions. I love this stuff.

And yes, I knew you want a quick answer and that is why I put the punchline up front.

Have a fine outing!

Lorne (a fan of the collegiate approach)

P.S. You are not getting an answer on the "pink" brake fluid because no one has one. That is the common reaction to something no one knows on an auto forum. I will speculate for you.

Brake fluid is NOT pink. It goes from clear or very mildly golden to dark brown as it ages. Testing brake and clutch fluid (the same stuff) with one of the new cheap testers ($10) is wisest. Transmission fluid is red. It is dyed for recognition, sorta like propane which has an odor additive for the same reason. In the very old days, I seem to recall that some people would use transmission fluid in the brake systems as well). Or perhaps the last guy used the same cone filler to fill both without cleaning in between. As well, your transmission is not far from your brake MC. Is the pink you are finding in the brake fluid reservoir or on the floor.

In any event, may I recommend a wise precaution for you? Whenever you get a car you are unfamiliar with, new or used, drain/change ALL the fluids ASAP and grease everything in sight. Axle, transmission, clutch hydraulics, brake hydraulics, coolant, suspension, motor oil..am I forgetting anything? And on little used cars, change the hoses as well. The alternative is to see these things fail you on otherwise happy Sunday drives and precious holidays. Working at your leisure with a beer in your garage is fun, doing the same thing in the dirt roadside with SWMBO annoyed is less fun.



Edited 2 time(s). Last edit at 2018-12-12 07:45 AM by GoMoG.

Well now I will bore you with My brake fluid story. I brought a friends 198? 4/4 to My garage to check the front end. As I drove it to Seattle on back roads I noticed the brakes were lacking. Beautiful 4/4 all waxed and shiny, with chrome wires flashing in the Sun. The brake fluid had not been changed since new I think. It had also sat for months without use. I called My Mentor and asked Him what to do. I really did not want to do a brake job. The answer was take the 4/4 back to the Owner, tell Him about the brakes and get out of this. Well I called the Owner and as He was not mechanical I offered to do the brake job for free however He must buy the parts etc. OK-Go for it. I got started and it was a disaster. Rebuild or replace all of the cylinders, and replace the pads and lining. I then started looking at the brake lines. They were steel but when I drained the fluid out there was rust, lots of rust in the fluid. I called My Mentor. "Bill when I do a brake Job I do it all. Replace everything, You can not risk the Owner's life with a half way job. Had He maintained His Morgan He would not be in this pickle". I called the Owner and explained what I felt I had to do and why. "No just fix fix the cylinders I will worry about the brake lines". I called My Mentor. "No return the Morgan and do not fix it". You get the drift! I ended up replacing the brake lines. It taught Me a lesson. Do not try to help somebody. Even for free. I lost a Friend and did a hellovalot of work. Any reputable brake shop will do this job. But like My Mentor says: "Repair/replace the whole system, if one wheel cylinder is leaking the others are about to leak".

I use DOT 4 if I can find it or DOT 3 if I can't and change the fluid every 2 years. My Mentor said do not use DOT 5 and spent 45 minutes lecturing Me on WHY!. MOSS Motors has information on the WHY.

Button

I don't think Mike Virr is on this group; otherwise by now I think he would have chimed in with his story of driving down a mountain pass when the brakes lost hydraulic fluid. He topped the system up with water and continued (of course thoroughly flushing the system later). I'm sure he drove gently until he was able to fix the leak, flush and refill. When all else fails, water will work to get you where you need to go.

Dunan

excellent story and advice...key is change the fluid every couple of years...stay ahead of the growing problems

Guys,

Find some room here in the waay back machine and settle in...

This car obviously has come straight from a time capsule. Back in the day, Girling sold different fluids for different specs. One of the popular Giling Brake Fluids was named "Crimson" (I've forgotten the other colors but I believe one of them was green).
So, this car was just filled up with the correct Girling Crimson Brake Fluid ...
Anyone still have a can of this?...Anyone remember the colors?

Never mixed my "colors" back in the day
Bill

Brilliant!

Just imagine how long the brake/clutch fluid had gone before it was changed!!



Edited 1 time(s). Last edit at 2018-12-20 10:42 AM by GoMoG.

Greetings... Whoa! That woke up some brain cells. I think crimson was the "high performance" juice. I've been playing with British cars since the mid 60's and heard of it but never used it. I seem to remember being put on to Castrol LMA due to its "Low Moisture Activity". I used a lot of Castrol products until their "think with your dipstick" add campaign a few years ago. Haven't use them since.

Tim(D.Y.M.)

Hi Tim,

A little bit of googling found me two old Girling colors, Red and Green. But no clue on which was for what. ATE currently makes a brake fluid that is dark blue.


Curious. How come?

Lorne

P.S. BTW, Lance mentioned those EZBleed bleeders to me. Do you know of them?

Oh... if you have a vintage Morgan (or other vintage British sports car, like my '50s Lotus), you will never get the brake fluid hot enough to boil it, unless you are racing, and then... You would have changed the fluid and bled the brake system prior to the race. If it boils, then it was full of water in the first place, and you should have flushed the brake system when you pried the thing out of the time capsule.

So, DOT 3/4 works fine. I have found that the Valvoline DOT 3/4 works fine and doesn't 't bother the seals on even my oldest cars (over 60 years old, but with brakes that have been rebuilt or re cylindered within the last decade or so as one might expect on car that is driven, and if you have not gone through your system and bled the brakes and flushed and changed the fluid over that period of time, well... I am amazed. Usually, the system would be rusted solid if there was water ).

Note that the brake fluid requirements are on the can, and you can find them on DOT 3/4 cans as well.

Anyway, you can safely flush and replace the fluid with DOT 3 or 4, BUT NOT DOT 5 as this may react with some brake flexible parts such as seals or O rings on these older cars.

Castrol LMA is a good one. So is Valvoline synthetic. If the parts you have rebuilt the brake system were made over the last 20 year or so, this will work just fine.

And...I have used the EZ Bleed screws. They work, but it is easier to use a proper pressure bleeder from Motive Power (about $45 with the proper cap) and just bleed the brakes under pressure. This takes just a couple of minutes, and doesn't require any pumping of the brakes to accomplish the job, even on a master cylinder that has not been bled on the bench.

I also have a Vacula, a vacuum bleeder that works quite well. This pulls fluid through the system and eliminates the bubbles and bleeds the master cylinder as well.

While all my cars don't have EZ Bleed screws, I don't miss them with a pressure bleed system. I can bleed the brakes by myself. I don't have to ask my wife to help. I find that this is a huge advantage, and... I don't have to wait. I can just bleed the brakes anytime I want

The bleed system also has an automatic filler as well, so I don't have to worry about filling the master cylinder.

So, PRESSURE BLEEDER... GET ONE! Not expensive, and they work. The caps fit the usual Girling and Lockheed master cylinders for both clutch and brakes. So easy that I bleed the brakes a few times a year, just to do it. AND, it also speeds the flushing of the brake system as no pumping is needed.

You will find a solid pedal after the pressure bleed process, just about every time.

One of those tools that you will find that you can't live without if you have a Morgan, or any other car that requires brake service.



Edited 2 time(s). Last edit at 2018-12-21 07:33 PM by SJM1.

I agree with everything said;however, I would emphasize getting the little brake fluid moisture tester about $15.
I have been pleasantly surprised that some cars might go longer then two years but I have also been disappointed some absorb too much moisture in a year.

My question was testing for synthetic or mineral fluids for which there is no device. But Lorne's Test in a jar was ingenious.

As a physicist / engineer may I humbly express an opinion about the proposed testers

The cheap testers use conductivity and sometimes capacitance to measure the moisture and then based on a set data in the memory of the instrument determine the danger level. The issue is that these preset data in my experience can give very false readings. In some cases even brand new fluid has been detected having moisture (Albait miniscule) while sometimes high level of moisture although detected has not shown dangerous level. This can be very misleading and dangerous. Besides Dot 3 Dot 4 and Dot 5 have all different levels and I have come across only 1 unit that can do all three and even then there are the same issues arising....and the price is a bit higher than $15....about $39.00

There are however only two ways for detecting proper moisture content accurately

1 need to heat up the fluid so that its effectiveness of the fluid can be determined...after all brake fluid become ineffective when brakes get hot and the fluid boils

2 Refractometry .....this method uses refraction and for those not familiar with the term ....remember when as a youngster you used to dip a rod or a stick in a body of clean water and it used to look as though it was broken that is the principle of refractometry.

A multifunction refractometer for automotive use which tests batteries, the coolant and brake fluid can be had for a bit more (about $42) but it is a much safer way more importantly accurate way to determine the amount of water in any media.

One pays the money and takes the choice. Please also consider that in order to have more accuracy one has to calibrate a tester to a KNOWN BRAND and store the figures in the system and then use to test the unknown old fluid of THE SAME BRAND.

Instead of all these it is more fun and more therapeutical to flush and fill with new fluid. If you love working on Morgan this beats any tests

---

I am always OK............. the trouble is with the others :-)

Well done Broadcaster. I will bank that! Thank you.

I am happy as long as people become more aware of these fluids and the need to regularly change them. How do we bring the horses to water?

Suggestions?

Lorne