This is a difficult post to write, because the technique really depends on the equipment you’re using to bleed the brakes. Also, because I was dealing with nasty brake fluid, I didn’t want to touch my phone, so I didn’t take my usual compliment of photos.
WARNING – DOT 4 brake fluid kills the car paint.
Even the smallest dribble – if left over time – will destroy your paint. The photo shows a small leak from my 360R’s master cylinder cap that I didn’t spot at a the time on a track day, even though I was using the kit-supplied “Race” master cylinder cap.
Personally, post IVA, I will remove the standard master cylinder cap and replace it with the “Race” item, because they are less prone to leaks. That said, it does mean I will lose the low brake fluid warning light, but its not like I am not going to check that when the bonnet is off.
I started by spanner checking all the brake line and hose joints, regardless of who fitted them, I didn’t find any problems, but worth a check.
Next I removed the DOT 4 warning label, even though it is an IVA requirement. However, AP Racing in their wisdom have made that label of a plastic that isn’t resistant to DOT 4. If you spill any on that label it will look a mess for the IVA, and replacements are difficult to find. So I decided to store mine until the test day, and I will refit it as part of my final prep.
The rubber bleed nipple covers can then be removed and a suitable spanner found for the bleeding process. I my case that was a 10mm for the rear and 11mm for the front.
Finally plenty of cleaning sprays and paper towels were on hand to clean any split fluid, remember cleanliness is the key here.
My process is simple, I do one round of bleeding with my Pagid Vacuum Brake Bleeder (https://pagid.com/product-range/tools/vacuum-brake-bleeder-and-refiller/) powered by my compressor. Then I do as many rounds as necessary with the good old two-person-technique, where one person presses the pedal repeatedly to force all the air out, until no air bubbles are exiting the bleed nipples, however small. For some reason this old-school technique always gets the better pedal feel.
I also had the help of my wife who made sure the master cylinder didn’t run dry of fluid and mean restarting the whole process again. It’s her I have to thank for the photos on this post.
A “round” starts at the left-hand side rear wheel, then the right-hand side rear wheel, then the right-hand side front wheel (outer first) and finally the left-hand side front wheel (outer first).
The vacuum bleeder is quick and clean, because it sucks the fluid into a large reservoir, but it has one major disadvantage: it pulls air through the thread of the bleed nipple. To combat this, I use a fair amount of grease around the nipple, obviously this all needs to be cleaned up once the bleeding process is complete.
With a good solid pedal, and some paper towel left in strategic places to monitor even the slightest of dribbles, it was then time for me to refit the rubber bleed nipple caps.
Now I have been able to apply foot brake pressure to the rear callipers, it’s now possible to fit and operate the handbrake cable, without fear of preventing the caliper adjusters from starting properly.
- 10mm and 11mm combination ring spanner (deep)
- 10mm and 11mm combination ring spanner (shallow)
- 11mm combination spanner
- 1/2″ flare spanner
- 9/16″ flare spanner
- 1/2″ combination spanner