trying to solve solve soft brake pedal since weekend

[Paisano]

I'm not sure if I mentioned this in a related posting. But it's on my mind.
I retrofitted in a new brake line to the junction over the rear axle housing, after I removed the rear ABS valve.
It has an upward slope over the gas tank because I couldn't feed it along the enclosed spaced inside the frame.
And I had to make a couple bends due to excess length.

After installing this new brake line, I did quick bleed and braking was fine.
I wonder if it is having trouble pushing air from this section of brake line after my front brake overhaul.

 

[SenorNoob]

Considering the pressure with which brake fluid flows when the pedal is mashed, it should push air right out...

 

[pentode]

There's another way to bleed brakes that doesn't require any special tools to do solo. Just run a hose from the bleeder nipple into a jar with clean brake fluid in the bottom - so that the end of the hose is always submerged. Then, crack the bleeder and pump the brakes yourself. All you need to do is make sure the master cylinder doesn't run dry.

When you pump the pedal it will push out whatever's in the lines, when you lift it'll just suck fluid back in. This does require having bleeders that fit properly - if the threads are loose, air will get in. Not usually a problem. This is how I do mine when I don't have a helper.

 

[Paisano]

Does this method risk moving the bubbles back and forth somewhere in the line before the air is expelled??

 

[pentode]

Does this method risk moving the bubbles back and forth somewhere in the line before the air is expelled??

No - assuming the bleeders don't leak air around the threads (shouldn't happen) the biggest risk is pumping all the fluid out of the master cylinder. It goes down fast so you need to keep an eye on that.

Although you can't really pump the pedal while watching the jar/container, I find if you're in a quiet environment you can hear bubbles escaping and sometimes your can even feel them in the pedal.

 

[Curious Hound]

Does this method risk moving the bubbles back and forth somewhere in the line before the air is expelled??

Not back and forth. Just one way.. But if there are bubbles there, you WANT them to move. They should be pushed down the line and out whichever bleeder you have open.

 

[Paisano]

It would be nice to resolve this without buying a power bleeder. Might be past that point.

I have done similar in the past and it was difficult keeping the MC reservoir full of fluid. In fact, it let in more air.
I have done brake overhaul and bleeding more than once. I never had this trouble.

 

[pentode]

I'm trying to refrain from speculating, but what you're describing sounds like either a _lot_ of air trapped somewhere, or something is broken. Soft pedal is one thing, pedal all the way to the floor... Even with a little air in the system you should have some pedal.
With the method I suggested, really all you need is a piece of tubing and a couple bottles of fluid just in case. And an empty coke bottle or jar or whatever. Good luck!

 

[Paisano]

Your comment on......'or something is broken.'
I actually looked at the brake linkage to see if something came loose. It didn't. There is a very small amount of sponginess.

I'm waiting for a power bleeder kit to arrive. It will take a few days. At least I will have it on standby, if old school method does not work.
I will follow up