• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

Flushing brake and fuel lines

Share this page

T

tdskip

Yoda
Country flag
Offline
Getting closer on the TR4A IRS. Engine is rebuilt and the rebuild A-type overdrive arrived from Brad (thanks Brad!). I'm going to clean up the engine bay this week and that got be thinking that I need to get going on the brake and fuel systems. That that me going on if I need to flush those lines first before buttoning everything back up.

I've rebuilt the master cylinders, and will be using new calipers, front brake lines and rear wheel cylinders but I am not planning on replacing the brake lines that run under the car.

This is the car that sat for 20+ years with fluids in it, I am assuming there is gunk in the lines that I don't want to get trapped in any of the new bits.

Tips and ideas for me?

Thanks!
 
Best practice is probably to go ahead and replace the hard brake lines. Last year when I tried to pull a short section of original brake line out of the parts bin, it literally snapped in my hands. Sure hate to have that happen right after a SUV pulls out in front of me ... and that sudden transition from no pressure to ~1000 psi would be just when it happens.

In the past, I've used methanol (methyl alcohol) for flushing lines, but denatured alcohol will probably do. Either way, you have to make very certain to get it all dried out, as any solvent remaining behind will lower the boiling point of the brake fluid (as well as potentially attacking the seals) leading to catastrophic brake failure at a bad time.

But for the project TR3, I just used DOT 5 brake fluid to push out all the old gunk.
 
I am probably not the most cautious person in the world but, mine sat for quite a while as well. I basically just bled the brake and kept the reservoir full. Funny when starting at the back left the sound coming from the tubing sounded like a old coffee percolator. Then all kinds of junk(solid and liqud came spurting out in to the collection jar. I ran about 2 quarts of fluid through and replace the rears cylinders, all's well so far. I replace the fuel line as I couldn't get flow through the old ones.
 
Tom,

I agree with Randall. Those lines are prime candidates for a problem down the road and after all that work, why take the chance?
 
Back
Top