AtoZ

Vehicle: 95 Accord Ex, Vtec, ABS

Re: HSM [Honda Service Manual // Helms Service Manual], ABS Bleeding Procedure ... Section and page: 19-129. I have several issues/questions regarding this procedure: But the main reason I am posting this thread, is that many people who work on their vehicles are under the assumption that the ABS and the regular brake system are 100% disconnected and THAT IS NOT TRUE. If there is air or a leak in your ABS, it will affect the regualr brakes. The manuals state the following:

1. Fill the ABS reservoir.
2. Place a hose on the ABS bleed nipple on the Modulator, put the other end of the hose in a container.
3. Loosen the bleeder and start the engine to activate the ABS pump motor. I assume the bleeder is opened 1/8 to 1/4, like the manuals mention for the fluid replacement procedure. Personally, I think that opening the bleeder 1/4 lets air back in around the bleeder threads, and keeps you in a bleeding loop that is virtually impossible to get out of.

4. Tighten the bleeder when the fluid starts to flow out of the bleeder ...

Q: I tried this without a helper to start the engine. I put the window down and reached inside to start the engine and then ran quickly to the bleeder. It can be done, but it would be so much easier if you have a helper. The fluid comes out with air very frothy, and then the fluid is solid, and then it goes back to being frothy, and just keeps going like this in a loop. The manual does not say anything about when to tighten the bleeder, with the froth or after it goes away, because either way there is fluid there, but the manual relates the sense that the fluid will be coming out very quickly, and that is why you are better off having a helper. It does comes out quickly, but you are able to get to the bleeder in time. So, the manuals are slient, rather poorly edited; and in that respect, what is not mentioned in detail or missing, is a major problem for mechanics, shadetrees, do-it-yoursefler's, without experience.

A: The answer is to shut it off when the fluid is solid, NOT when it first comes out, because it may be frothy and that is fluid with air, which needs to be eliminated.

5. Stop the engine when the ABS pump motor stops ...

Q: When, after the first pump motor run [shortly after start up], or after the second pump motor run [about 15 to 30 seconds later]? ...

Btw, I was just replacing the older darker brake fluid as general maintenance. I finished bleeding the brake calipers and that went well. Brake pedal was tight, the car stopped well, no Brake light, no ABS light. But when I bled the ABS, I made one mistake, I opened the bleeder a bit when the hose had no fluid in it, and as a result, the vacuum that was there sucked air into the ABS modulator, and I got an ABS light, and a ton of bubbles out of the bleeder. So, I had to start all over.

I was able to get back to where I was before, where I can get the majority of the air out, but I cannot seem to get rid of the last few micro air bubbles. [I can see them in the clear tubing I use] After those last few bubbles bleed out, the fluid is solid with no more air. But after I fill the reservoir and start the engine to run the ABS pump, when I go back to the ABS bleeder to make sure all the air is out, those few micro air bubbles are back again. These micro bubbles seem to be the last remaining issue - regardless of which procedure I use to bleed the air.

Q: What is causing these few micro bubbles? Is it normal? ... Is it impossible to remove 100% of the air? ... Is it really air, or is it pressure created bubbles from the high pressure ABS pump? ... is it the NPT bleed nipple threads that are inherently flawed by design, which, when loosened allow the vaccum to suck air in around them?