Leeper you are mistaken. No brake system in the automotive world is fully sealed- not from moisture. You would never need to change fluid if it was. And the reason they went to Dot5 is for precisely that reason.

And dont forget its not completely sealed at the piston end either. And isnt it ironic that those are the only two places you will find dark fluid.

 

"Once installed, moisture diffuses into the fluid through brake hoses and rubber seals and, eventually, the fluid will have to be replaced when the water content becomes too high"

 

Perhaps you need to reread my comment. I was referring to you as having greatly contributed to this forum.

I have no problem disagreeing with you nor anyone else on this forum. If you believe you are correct, so be it. It requires far too much effort to go to great lengths to prove the inaccuracy of much of what is said on all forums, including this one.

 

Paid $100 at Jag dealership. Even if I wanted to, I hate fooling with brake fluid as even one drop going somewhere can mess up the paint.

 

Cat - perhaps I did misread your posting regarding contributions.

Q&C - we are both right. The cap as Cat suggested is in fact a seal and not "open" as he stated otherwise either hitting a puddle or washing the engine compartment would create huge issues. The cap and the diaphragm are there to insure a seal stays that way. The system is as sealed as it can be though moisture can leach in through rubber brake lines, sometimes through the metal tubing, and through the various seals throughout the system. Its as sealed as they can make it not open.

Also I argued the claim that the discoloration is due to moisture (water) which I stand behind. I'm well-aware of the ATE Blue fluid as that's what I was using until they changed the regulation requiring amber fluid, I still use and prefer the ATE brand. Q&C you mentioned that heat is not an issue, actually it is at the caliper side where temps get quite high - if you doubt me there go drive a little spirited then touch your calipers where the bleed valves are... the fluid color does change as a result of heat also as well as contaminates

The darkness being only at the valve and MC hasn't been what I've experienced, when I change out my fluid it stays the same color throughout which makes it easy to see when you've exited the old fluid and hit the new stuff, not only at the ends as you described.

With regard to brake fluid destroying paint - partial truth/fear. It will do so if left there to do the damage. Anytime one is changing the fluid, or even topping off your brake fluid, just keep water nearby it will immediately address that. For the most part you're in the wheel well at the valve end with a small plastic tube going into a can, jar, or bottle to collect the old fluid. At the MC side you're pouring a little fluid from a small bottle or small can so its unlikely you'll spill, if you do just spray it with water so it's really not a concern/fear. Doing this service is very easy and very safe but most will choose to have someone else do it. My Motive bleeder makes life easy as would most of the others out there or even having someone step on the brakes but that does take longer and some coordination.

$100 at a Jag dealership, if it was actually done properly, sounds like quite a deal! I would still go check my bleed valve nipples to make sure they actually opened them and didn't just change the fluid at the MC. As said earlier it's about an hours job total most rates I've seen at dealerships run $125-140/hour with an hour min charge. A number of Jiffy Lubes, as well as other places, got nailed for lying about actually doing that service yet still charging for it. "Like Reagan said - "trust but verify".

 

I still do this on my other vehicles but it had been done by the dealer on the XKR under the CPO coverage. I suspect I will either have to do the next one or take it to the dealer. My process is simple. I use the turkey baster to remove the fluid in the brake bottle. Put the used fluid in a clear measured container. I have on my other cars replaced all of the brake bleed nipples with a product called "speed bleeders". These nipples have a check valve built into them. I pull all 4 wheels off and put the bleed hose on the RR caliper. Crack the nipple and go in and pump the peddle about 5 times. This usually cleans the line out. Go back and fill the bottle. Then close the nipple and do LR , then RF and then LF. Makes it a 1 man job and it usually takes longer to pull the wheels . I notice that some calipers have the bleeder located so you can get at it from the outside without removing the wheel but in my other cars this is not possible. With the old Ferrari I changed all of the fluids annually. By the way did we ever get a dealer price for this work.

 

Thank you, that is what I do also. Turkey baster to remove from MC, then refill with clean fluid to start the flush procedure. I use either a vacuum pump borrowed from my buddy, or in the case of my Jeep which the pump wasn't strong enough to draw the fluid, I had the Wife pump the pedal. We did the pump-hold, tighten bleeder screw, release pedal, open bleeder nipple, pump-hold, and so forth. Took 10 minutes to do all 4 wheels.

This thread has taken what is simple and made it complicated. Silliness I tell you.

 

This one is mild compared to some. Of course, it's possible that they're not quite done with this one yet.

 

Wish there was a simple and effective way- there isnt.

Speed bleeders have been rendered useless, they let air in eventually. And wait till you break one in the caliper.

Pumping the pedal does not remove all the air- if it did there would be no need for speed bleeders and countless other products.

Pulling a vacuum at the caliper does not necessarily pull all the air out, all screw in type of valves let some air in past the thread.

At the factory they use pressurized fluid and pull a vacuum on reservoir.

 

Sorry but it works for me and that's all it needs to do. Try being constructive . It would have been easier just to comment that you don't prefer to use them as you have had a bad experience with them.

 

most all the reviews and those I know that have used Speed Bleeders love them, I couldn't be happier with my Motive pressurizer then utilizing the original bleed nipples on the car... read reviews on both just chose to go the route I did. Also have not heard of issues when using the foot pump method as long as you drive it around right after then do one last bleed-out to ensure air bubbles are gone. Unless the user is driving hard on a track I highly doubt any of these methods will ever incur an issue.

When doing our sport race motorcycles we would use the lever (same as a foot pressing the brakes) to create the pressure then bleed the old fluid out. Once we got to the new fluid we would either drive it for a short distance and do again to get the last tiny bubbles out or hit ir repeatedly with a rubber mallet. We had a LOT more riding on the outcome then a normal driver in a Jag.

Lastly also know that when a dealership or indi changes it they are utilizing either a vacuum or pressurized system just like JT and I have mentioned here not both (not the foot method which is also fine for most all but racing uses) so people have no choice in using what the car may have been serviced with during manufacturing

 

It's like I can predict the future.

 

Common in aviation, but not automotive.

ABS circuits would be a worry.

 

I agree that clear to amber color is a requirement under FMVSS for DOT3, DOT4 and DOT5.1
but not DOT5.

But I am not aware of any requirement that the fluid darken.

What specific citation can you point to in the FMVSS 116 that shows
otherwise?

 

http://www.sector111.com/images/prod...ke%20Fluid.pdf

except that most stainless hoses cannot meet FMVSS 106.

I would rather bleed and flush regularly than count on a stainless braided brake line
to not chafe and burst.

 

It is my understanding that Jaguar recommends Super Dot 4 Brake Fluid.

The preferred/recommended brand is ITT Super Dot 4 which has now superseded the older Shell ESL Super Dot4.

I have ordered a liter of Pentosin 1204116 Super Dot 4 Brake Fluid and will use it to make the brake fluid flush.

Our British Car Club of Southern New Mexico has a master mechanic that will complete the work, and I will assist.

Should work out well. I am interested to see the color coming out of the lines and will report back to you.

Thanks for all the input. Every member here has important input and are great members.

..

 

I have an easy system not mentioned here yet- however I would like to discover a more accurate way of making sure that the brake lines are to factory specs- because this car has better braking performance than a Lamborghini Gallardo fitted with $18,000 brakes.

I told the kid next door that the first step in learning how to work on a sports car is being able suck out the old brake fluid with a silicone tube. Just kidding, use a check valve attached to my 9liter vacuum canister- which wont lose its vacuum till I disconnect the check valve. The problem, I one doesnt get 100% of the air.

Great writeup here in all the disadvantages. https://en.wikibooks.org/wiki/Automo...Braking_System

 

Working with developer chemical for film as a kid, one quickly learns that there are very few materials, if any, that can successfully keep air out. The plastic used in the coke bottles was about the best thing- they have the same problem with diffusion out.

 

Several Lotus owners who track cars swear by SpeedBleeders.

 

All of a sudden I feel the urge to have my brakes bled. I will let the dealer do it. No sucking and pumping for me!