• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Repacement of brake fluid

Share this page

tahoe healey

tahoe healey

Yoda
Country flag
Offline
I am going to be replacing the brake fluid and I'm looking for some "how to" help. There are no leaks or problems but the fluid is (very) "old" as per the article in the recent monthly magazine.
My questions:
Best way to expel all the fluid? Gravity or pump? Do I need to remove each wheel cylinders to get that last drops out?
How to remove fluid from the servo or is it even necessary?
I am planning to remove the master cylinder to replace the guts just because it would be a good time to do so. Can I tell just by feel if the cylinder walls are good and how much corrosion is acceptable (if there is any)? I have a honer but have been told not to use it.
What is the best way to remove the reservoir with out destroying the new paint? I can suck out most of the fluid first.
Should I use a compressor to blow out the lines?
How much fluid should I have on hand?
Thanks. I hope I haven't forgotten anything. Please feel free to add all your suggestions.
TH
 
Thanks. I hope I haven't forgotten anything

Well you go messing around with the reservoir and you introduce the clutch system too.---Keoke--- :laugh:
 
If the m/c "feels good" you can replace the rubber seals without removing it (they can actually be honed in place too, if need be). This requires doing the work from the footwell, but if you're still flexible, can be A LOT easier and faster than removing the m/c.

Plan on "wasting" about a quart of brake fluid. Just keep flushing it through until nothing but clean fluid comes out.

Suck out most of the fluid before replenishing; I wouldn't remove the reservoir if you don't have to.

I assume your brakes were working okay before, so I wouldn't mess with anything that doesn't need to be messed with!

Brake fluid SHOULD be replaced annually, as it absorbs moisture (moisture in your brake system is what leads to rust, rust leads to more work & $$$$). I try to do my cars at least every couple of years (that's BMWs recommended interval, and they have smart engineers...).

Contrary to popular belief, the Healey does lend itself to pressure bleeding. Conveniently, the same cap for the BMWs fits the Healey! I use this little gem from Bavarian Autosport: https://www.bavauto.com/Assets/inst_pages/ins030.pdf

The pump is a little different on mine (more like a garden sprayer...). but the effect is the same. I used mine last night (for probably the 150th time) on a 1998 M Rdstr.

pb03k.jpg
 
Based on my experience of long neglect, I would first suction out the old fluid from the master cylinder tank. Then rebuild the rear cylinders with new seals checking for corrosion on the walls. If any found, sand with very fine (400 grit) sandpaper. Then remove and rebuild the disk calipers checking for corrosion on walls of cylinders and pistons. Replace any corroded pistons and all seals and boots. Replace the three rubber brake hoses (2 at front wheels and one at back axle housing). Then rebuild master cylinder. Bench bleed master before reinstalling (I haven't done this but there are threads on this forum how to do this.). Fill tank with fresh fluid from a new can. Then bleed each wheel using standard techniques of a helper pushing down on brake pedal with you having a clear tube attached to the bleed nipple open. Close nipple and tell helper to raise pedal, repeat until no air bubbles come out on the peddle downstroke. Start at right rear then left rear then right front then left front. Make sure to replenish master tank reservoir way before running out of fluid, after doing each wheel.
 
Then bleed each wheel using standard techniques of a helper pushing down on brake pedal with you having a clear tube attached to the bleed nipple and immersed in a container of clean fluid.

Good call---Keoke
 
Keoke, thanks for the clarification - that's what I do and should have said. :iagree:
 
Conventional brake fluid is very hard on the paint. To minimize problems with BF on the paint, pump the system dry first. Use a piece of hose attached to the bleed nipple and pump out the system into an old quart jar. After it is empty, wait an hour and do it again to get out what has settled.

I never rebuilt the master from inside the car. If you remove it from the car first, you again reduce the chance of spilling brake fluid on the paint. Some drops will come out when you remove the lines, but if you have pumped it dry, it should be minimal.
 
Back
Top