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Wanted- Solvent for dried brake fluid

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Sebring222

Sebring222

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Recently I purchased a car that had new brake lines, new brake master, new clutch master and a new clutch slave. The system was filled with standard Dot 3
fluid and then left to sit for more than 10 years. The result was that the brake fluid actually "dried out". What remains looks like dried tree sap. Of course this is in the brake lines as well. Is there a solvent I can use to remove the residue and flush out the lines. Thanks for your help with this!
 
Have you tried acetone? Of course whatever you use, you're probably gonna have to rebuild the master cylinder, wheel cylinders, & calipers.
 
I really haven't tried any solvent yet. The cylinders were all brass sleeved, so I'm hoping that I can get away with just replacing the rubber components after removing the brake fluid residue. You can be absolutely sure that I will use silicone fluid when I refill the system.
 
Ol' rustbucket had the same problem. I topped off the master cylinders with new brake fluid and pumped the clutch pedal and brake pedal a few times each time I was in the garage. About a week later, the new fluid had dissolved the crud enough to move fluid through the lines. The clutch cylinder looked the worst, but it actually worked! Denatured alcohol has been recommended to flush the lines.

I'm sure the seals are all junk. Everything will get rebuilt eventually. This was just an experiment when I first dragged her home and was evaluating all the systems.
 
I ran into the same thing. New fluid, new m/c's new slave for the clutch and rubber hoses. Blew out the lines with acetone installed the new rubber lines and filled the system. Flushed the system a few weeks later and again after changing out the rear brake cylinders after they started to leak. Been nice and clean since.
 
rustbucket said:
Denatured alcohol has been recommended to flush the lines.
Click to expand...

Yessiree. Just be thorough about blowin' everything clear after that. The alcohol can attract moisture if left behind. I don't like to use acetone on flex lines but it will work for the metal ones.
 
The product Brakleen (should be available at any auto parts store) works really well for me, and it doesn't leave any residue. It also is an aerosol with a tube that you can squirt down the lines. As I recall it is primarily methylene chloride (much more toxic than acetone, don't get any on you).
 
The Brakleen idea sounds like a good one that I haven't tried. I've left the three master cylinders sitting with new fluid in them on the bench. The pistons are stuck. I've moved the pistons down the bores about an inch so the return spring will keep some pressure on them. If I don't have any luck in the next few days I'm sure I'll use air pressure to blow the pistons out of their bores and just rebuild each one. They have been brass sleeved.
 
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