binhsterbinh

I think I possibly let the master cylinder reservoir go dry while bleeding my brake system with my new speed bleeder screws. With speed bleeders, I didn't realize how fast fluid is expelled as opposed to the 2 person method. This is all following the upgrade to Stainless Steel lines.

Is it necessary to bench bleed the master cylinder again after letting the reservoir go dry? I found an article (click here) from honda-tech stating that the with the modern Honda master cylinder design, bench bleeding isn't necessary?

I've already activated my ABS system quite a few times now in the rain to make sure I've cycled out any possible air out in the ABS controller; however, before I re-bleed the system, should I do anything to make sure I've purged all the air out of my master cylinder? I think most the air left the the system out of the driver rear brake line, but I'm not positive.

In the past, I've done the cheater method of simply having someone press and hold the pedal down while I loosen up one of the brake lines at the master cylinder and then tightening when they've reached two-thirds pedal travel. Then I have them pump the system to build pressure again and repeat that process a few more times. Then I move onto the 2nd brake line at the master cylinder. Basically like bleeding at the calipers minus the clear hose and just a catch rag. Anyone know if this is still pretty valid and okay process on the TL?

So far without the 2nd bleed process, the pedal feels decent but a little soft and feels quite a bit more touchy than it did. Getting full wheel lockup and ABS to engage takes almost no pedal effort. The pedal does not go to the floor or anything, so maybe I'm just paranoid.
Thanks.

nfnsquared

What are you basing this thought on? If it's because you saw the level go down beyond sight in the neck, that's no quarantee that it went dry. There can still be a lot of fluid still in the body of the cylinder even though you can't see if from the top.

binhsterbinh

I was able to find the Master Cylinder replacement procedure in the Service Manual - still no mention of bench bleeding. All it says is "Install master cylinder in the reverse order of removal." Can anyone chime in here please if you know whether bench bleeding is required? Thanks.

Turbonut

iTrader: (1)

No, just fill the MC and bleed the brakes normally.

binhsterbinh

While pumping the brake while I had the speed bleeder valve cracked open at the driver rear wheel, I saw heard the sound of air somewhere in the system. I thought it was air coming out of the caliper, but later believe it was really just the reservoir going dry and gasping for fluid and just getting air. It was dark and hard to tell, but I did have to fill a good 12oz of brake fluid into the reservoir before it got back to the max line.

I then went back and bled the system again after this mishap. Most of the small air bubbles were found in the driver rear caliper as well. This line was also the one that was open the longest when switching to stainless steel brake lines.