Croc Posted October 3, 2011 Share Posted October 3, 2011 Just a friendly heads up to the seven community. I noticed today my brake hoses were sweating brake fluid. On closer inspection they were starting to perish. The fluid was drained to find it full of small black flakes suspended in the fluid, I guess coming from the inside of the hose. Given this was a newly constructed car in March and has only done 1100 miles in 6 months, I guess Caterham UK specc'ed the kit with the wrong hoses for the brakes - a bit disappointing and of obvious concern given I did 2 track days with them in July. Even if you have not replaced your brake hoses lately, you may want to give your hoses a good inspection for signs of brake fluid sweating. New brake hoses coming up for me....:leaving: Link to comment Share on other sites More sharing options...
blubarisax Posted October 3, 2011 Share Posted October 3, 2011 (edited) Mine sweat too when the humidity is very high, I suspect we have the same setup. Only noticed it a couple of times when it was near 100% humidity. I have changed brake fluid several times this summer (uprated rear brakes/bias valve/Pagid pads/race master cylinder) and have not noticed any black flakes. As long as you have fluid in the reservoir and the fluid is not contaminated it should be safe, right? I'm sure you have thoroughly researched the best hoses...please share your thoughts. Edited October 4, 2011 by blubarisax Link to comment Share on other sites More sharing options...
Croc Posted October 3, 2011 Author Share Posted October 3, 2011 Clearly contaminated fluid is a problem. If you say yours is clean then ok but I am wary of any brake line sweating. I was taught it was a bad thing. I prefer myself to get hot and sweaty instead of my brake lines. Replacements are a toss up between some conventional Raybestos lines or some snazzy looking Wilwood ones. Guess what I will fall for.... Link to comment Share on other sites More sharing options...
S1Steve Posted October 4, 2011 Share Posted October 4, 2011 My s1 has Wilwood stainless steel brake lines and I have had no problems with them in 9 years. Wilwood also has a great tech line that you can call and get some real answers. Glad you caught this brake problem before it turned ugly. I have a nice brake bleeding tool if you need it. Link to comment Share on other sites More sharing options...
blubarisax Posted October 4, 2011 Share Posted October 4, 2011 Sounds like Wilwood line is good. Wonder if they have any spiffy carbon fiber lines? Link to comment Share on other sites More sharing options...
The Stig Posted October 4, 2011 Share Posted October 4, 2011 The Goodridge hoses are great too. Either off the shelf or get them made. Not sure where in NJ as I used to live a few miles from their factory in the UK so had flexible hoses throughout the car. Looked great and totally reliable. I believe they do coloured stainless too! Most F1 cars use Goodridge hoses. Link to comment Share on other sites More sharing options...
Kitcat Posted October 4, 2011 Share Posted October 4, 2011 Plain old stock Caterham units fine after 30K miles, 13 years. Did brake flush 3x in last 16K miles. Link to comment Share on other sites More sharing options...
bsimon Posted October 4, 2011 Share Posted October 4, 2011 Mike, I'm guessing you have the upgraded braided Stainless hoses on your CSR Generally, stainless brake lines are simple extruded Teflon hose encased in stainless braid. If you are seeing black specs and weeping, I would imagine that they are not Teflon but nitrile (Buna-N, NBR) hoses meant for fuel or oil. Nitrile lines are not pressure rated for brakes. Brake fluid eats nitrile as well. Methinks someone speced the wrong materials at Caterham. Scary... Link to comment Share on other sites More sharing options...
jlumba81 Posted October 4, 2011 Share Posted October 4, 2011 Could it be an issue w the brake fluid being not compatible w/ the brake hose material? DOT 3 vs DOT 4 vs DOT 5? Link to comment Share on other sites More sharing options...
Croc Posted October 4, 2011 Author Share Posted October 4, 2011 Generally, stainless brake lines are simple extruded Teflon hose encased in stainless braid. If you are seeing black specs and weeping, I would imagine that they are not Teflon but nitrile (Buna-N, NBR) hoses meant for fuel or oil. Nitrile lines are not pressure rated for brakes. Brake fluid eats nitrile as well. Methinks someone speced the wrong materials at Caterham. Bob - Thanks for the technical explanation - this makes perfect sense now. I am useless on the technical properties of the materials being used but I instinctively know when I think I have a problem. I am troubled by the potential for other new kit owners to be blissfully unaware of a problem like this all because of a bad batch of hoses not manufactured to the correct specs. Steve/Martin - Thanks for your thumbs up on Goodridge and Wilwood. I will look at them closer today. Link to comment Share on other sites More sharing options...
xflow7 Posted October 4, 2011 Share Posted October 4, 2011 Mike, did you already alert Caterham to the problem? If they have a bad batch of brake lines they need to know about that. Dave Link to comment Share on other sites More sharing options...
Croc Posted October 4, 2011 Author Share Posted October 4, 2011 Mike, did you already alert Caterham to the problem? If they have a bad batch of brake lines they need to know about that. Dave I got the vmail at Caterham USA and left a message. I am having a race car engineer look at them to confirm diagnosis as well. Link to comment Share on other sites More sharing options...
Kitcat Posted October 4, 2011 Share Posted October 4, 2011 Croc: What abt a posting on Blatchat? Link to comment Share on other sites More sharing options...
The Stig Posted October 4, 2011 Share Posted October 4, 2011 I have a nice brake bleeding tool if you need it. What is the magical bleeding tool you speak of? Need to replace fluid so looking for something other than piece of pipe and a helper. Link to comment Share on other sites More sharing options...
Croc Posted October 4, 2011 Author Share Posted October 4, 2011 Croc: What abt a posting on Blatchat? Maybe. I need to give Caterham opportunity to respond as Dave rightly pointed out. Steps I am taking are: 1) Friendly heads up here plus confirm my suspicions. 2) Trusted mechanic inspected and confirmed Bob's diagnosis this morning. 3) The CSI boffins we use for technical insurance claims have the brake lines and the fluid sample and I will wander around to them later today for the lab report. 4) Talk with Caterham and give them a chance to get the message out. What is the magical bleeding tool you speak of? Need to replace fluid so looking for something other than piece of pipe and a helper. You want one of these or similar: [email=http://www.harborfreight.com/brake-bleeder-and-vacuum-pump-kit-92474.html]http://www.harborfreight.com/brake-bleeder-and-vacuum-pump-kit-92474.html[/email] Wish I had one years ago. Link to comment Share on other sites More sharing options...
S1Steve Posted October 4, 2011 Share Posted October 4, 2011 Stig, Mine looks like the harborfreight unit. Thats also a good price for one. I also tryed a model that plugs in my Aircompresser, but I thought it was over rated. And it was alot more money. Just a little heads up on the subject, I always do the clutch when I bleed the brakes. Clutch fluid always seems crapped up and darker than the brake fluid. I have know idea why. Mike, CSI boffins, Thats funny !!!!! Link to comment Share on other sites More sharing options...
bsimon Posted October 4, 2011 Share Posted October 4, 2011 Mike, I'm real curious. Are the hose ends crimped or the reusable type? Link to comment Share on other sites More sharing options...
Sean Posted October 5, 2011 Share Posted October 5, 2011 I picked up a SpeediBleed kit - the 400 model cap fit on my Caterham fluid reservoir. Hooks up to a tire, and then dial in the desired pressure on the in-line valve using the gauge (~6-8 psi worked well for me). Then open a valve until clean fluid shows, and close it. Couldn't be simpler. I did not fill the jug provided with fluid at all, but chose instead to keep topping off the reservoir. This method is cleaner, but you have to watch it carefully because if the fluid in the reservoir gets too low, you have to start over again. Link to comment Share on other sites More sharing options...
blubarisax Posted October 5, 2011 Share Posted October 5, 2011 Mike, are you using synthetic fluid? I had no problems before I switched. Karl Link to comment Share on other sites More sharing options...
JohnK Posted October 6, 2011 Share Posted October 6, 2011 Bleeding: Power bleeders are a bother, especially since you have to use more fresh fluid and match the fitting on your car's reservior BUT once you get things set up, you get to flush the system much more easily. I have read that the usual method of pulling the fluid from the caliper end may draw air in around the piston seals and introducing air into the line - leaving the pedal spongy - although I've never experienced that myself. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now