Author Topic: Cleaning clogged brake lines  (Read 5327 times)

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Offline midnightrider

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Cleaning clogged brake lines
« on: May 24, 2010, 02:14:46 PM »
Hi,

I saw a few posts that discussed this, but there was not much about cleaning clogged brake lines; most of the advice was to replace.  Well I am on a tight budget and $33.00 per line is steep.  I don't want to go SS braided at this time either. 

So, has anyone cleaned their clogged lines?  Any ideas?  I got the lower line clear because I was able to jam a coat hanger into it, but the upper line is different as you cannot directly access the hole.  I've tried tons of brake parts cleaner and jamming various things into the line, but cannot get anything solid in there because the holes are inside of the ring that allows the 90* connections at the master cylinder and the brake light pressure switch. 

Any thoughts on boiling?

Thanks for any help.
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Offline cameron

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Re: Cleaning clogged brake lines
« Reply #1 on: May 24, 2010, 02:18:08 PM »
Maybe you could soak the whole thing in some kind of solvent for a couple days?
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Online MCRider

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Re: Cleaning clogged brake lines
« Reply #2 on: May 24, 2010, 02:22:57 PM »
Access to a compressor? Blow 100psi thru it. May have to seal it up around the banjo, shouldn't be too hard.
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Offline Rio_CB750

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Re: Cleaning clogged brake lines
« Reply #3 on: May 24, 2010, 02:30:52 PM »
i took my clogged lines to a local motorcycle shop and they matched them, 20 bucks for two lines, they were different lengths, slightly longer, but it made no braking difference.  got a old shop near you?
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Offline midnightrider

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Re: Cleaning clogged brake lines
« Reply #4 on: May 24, 2010, 02:32:59 PM »
Maybe you could soak the whole thing in some kind of solvent for a couple days?

What solvent would be rubber safe?
1972 CB350 Four - "The Green Hornet"
http://forums.sohc4.net/index.php?topic=84975.0


I love being alive and I will be the best man I possibly can; I will take love wherever I find it and offer it to everyone who will take it... seek knowledge from those wiser and teach those who wish to learn from me.
-- Duane Allman's epitaph



Offline midnightrider

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Re: Cleaning clogged brake lines
« Reply #5 on: May 24, 2010, 02:34:24 PM »
i took my clogged lines to a local motorcycle shop and they matched them, 20 bucks for two lines, they were different lengths, slightly longer, but it made no braking difference.  got a old shop near you?

Got a couple of sport bike shops and a couple harley shops.
1972 CB350 Four - "The Green Hornet"
http://forums.sohc4.net/index.php?topic=84975.0


I love being alive and I will be the best man I possibly can; I will take love wherever I find it and offer it to everyone who will take it... seek knowledge from those wiser and teach those who wish to learn from me.
-- Duane Allman's epitaph



Offline Nikkisixx

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Re: Cleaning clogged brake lines
« Reply #6 on: May 24, 2010, 06:43:12 PM »
I'd advise you to save your nickels and get new lines, you're just peeing into the wind otherwise.  Now that my PSA is out of the way, denatured alcohol (available in the paint isle at your local hardware store) would be your solvent of choice.
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Offline BLUE71TURBO

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Re: Cleaning clogged brake lines
« Reply #7 on: May 24, 2010, 06:51:48 PM »
 You are messing with your life and others as well !!  Don't cheap out when it comes to brakes, especially on a motorcycle !  A friend of mine did and he spent 6 months in a hospital, 1 year in rehab and lost his house to help pay medical bills !  He had to start all over in his life. He's still struggling 5 years later.   :-\
   Don't rush the important things when it comes to a motorcycle !!!   ;)
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Offline CycleRanger

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Re: Cleaning clogged brake lines
« Reply #8 on: May 24, 2010, 07:19:55 PM »
If your brake lines are clogged it means the inner lining is rotten and collapsing. 
Get new lines.
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Offline BobbyR

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Re: Cleaning clogged brake lines
« Reply #9 on: May 24, 2010, 07:41:33 PM »
I'd advise you to save your nickels and get new lines, you're just peeing into the wind otherwise.  Now that my PSA is out of the way, denatured alcohol (available in the paint isle at your local hardware store) would be your solvent of choice.
Denatured Alcohol is the main ingredient of brake fluid. When it evaporates it leave the rest of the ingredients behind. It will redissolve them very quickly. If your lines are degrading which they probably are you really should change it. All you really have is the front brake. Try Alcohol and give the lines a good look. When you get a couple of bucks, buy a new line ASAP. You are truly betting your life on the old one.
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Offline Alan F.

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Re: Cleaning clogged brake lines
« Reply #10 on: May 24, 2010, 07:56:09 PM »
If your brake lines are clogged it means the inner lining is rotten and collapsing. 
Get new lines.

He's right, put the little red straw onto a can of brake cleaner and shoot some through your brake lines. if it comes out the other end you're ok for now. But don't fool yourself into thinking a 30 year old brake line will safely get to its 40th year.
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Offline fmctm1sw

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Re: Cleaning clogged brake lines
« Reply #11 on: May 24, 2010, 08:56:37 PM »
So, has anyone cleaned their clogged lines?  Any ideas? 

Cut the end off an old clutch cable and fish it through the line.  But yeah, if you have the money you should replace them as mentioned...
re: burnouts thread 
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Dude is that a tire ? or an O-ring..??

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Offline midnightrider

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Re: Cleaning clogged brake lines
« Reply #12 on: May 24, 2010, 09:31:14 PM »
Fully noted about the new lines; thank you for the advice everyone;  I will get them asap.

I did get it clear today. I used big guitar strings and lots more brake cleaner.  The clog was actually very small, with the rest of of the brake line clear and easy to push the string through; it seems to me that this would be more indicative of localized formation and drying of particulates than of collapsing lines though  ??? 
I mean no disrespect to those that have said otherwise and will still be heading their advice as soon as possible; it is just an observation of mine when I broke through the clog. 

Thanks for the suggestions and the constantly-needed reminder for cheapies like me to play it safe.
1972 CB350 Four - "The Green Hornet"
http://forums.sohc4.net/index.php?topic=84975.0


I love being alive and I will be the best man I possibly can; I will take love wherever I find it and offer it to everyone who will take it... seek knowledge from those wiser and teach those who wish to learn from me.
-- Duane Allman's epitaph



Offline Bodi

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Re: Cleaning clogged brake lines
« Reply #13 on: May 24, 2010, 09:43:05 PM »
"Denatured Alcohol is the main ingredient of brake fluid."
This is entirely wrong. There is no alcohol (zero, nil, none) in brake fluid. DOT3 and DOT4 are various glycol esters, DOT5 is a silicate fluid.
Plus, "denatured" is a term to describe ethanol (the alcohol in stupefying drinks) with a poison added to it making it unpleasant to drink: this allows it to be sold without the added excise and sin taxes added to drinking ethanol.



Offline CB500_k2

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Re: Cleaning clogged brake lines
« Reply #14 on: May 24, 2010, 10:12:25 PM »
The brake lines are pretty narrow gauge.  I used a fine copper wire to chase out crud from my 500's brake lines and it worked.  The brakes continued to be a bit mushy and I finally replaced the line with a new one.  Sadly,  the brakes remained a bit mushy and I have lived with non Ducati braking for the last several years.  I guess twin disk four piston Brembos stack up well against the the old CBs
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Offline CycleRanger

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Re: Cleaning clogged brake lines
« Reply #15 on: May 25, 2010, 08:54:03 AM »
Fully noted about the new lines; thank you for the advice everyone;  I will get them asap.

I did get it clear today. I used big guitar strings and lots more brake cleaner.  The clog was actually very small, with the rest of of the brake line clear and easy to push the string through; it seems to me that this would be more indicative of localized formation and drying of particulates than of collapsing lines though  ???  
 Thanks for the suggestions and the constantly-needed reminder for cheapies like me to play it safe.

Sometimes some folks don't appreciate the answers to the questions they ask here.  ::)
Thank you for taking everyone's advice in the spirit in which it is intended! :)

(And you might be right about your brake lines.  We can't see them so you can be a better judge.)
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