I am lost...
I have bled brakes on my motorcycles lots of times without any problems (using the oldschool method with tube in jar).
Now, on my FJ1100, I have fitted new braided brake hoses and rebuild the calipers with new seals and stainless steel pistons. I.e. the brake system was completely dry.
I have now added brake fluid and tried to bleed it for 3 hours... There is no resistance whatsoever to feel in the brake lever :mad:
I pump the lever maybe 15-20 times, loosen the bleed nipple and let fluid and airbubbles out, close the bleed nipple and repeat.
I have bled both calipers and both antidive units (yes, they are still in place, and works :dance2:). I am now at a point where I am only getting very few small air bubbles out, if any. But, the brake lever still just pulls to the handlebar without resistance...
Is there a special method needed because of the antidive units? Any advice is highly appreciated :good2:
You must first get all the air out of the master cylinder, so it can push fluid.
Sometimes, it's as easy as loosening the brake line leading from the master, and covering the hole with your finger. Actuate the brake lever, and allow your finger to provide resistance to the fluid. You'll feel it when the master cylinder starts working.
Steve
Quote from: Steve_in_Florida on September 05, 2015, 08:51:55 AM
You must first get all the air out of the master cylinder, so it can push fluid.
Sometimes, it's as easy as loosening the brake line leading from the master, and covering the hole with your finger. Actuate the brake lever, and allow your finger to provide resistance to the fluid. You'll feel it when the master cylinder starts working.
Steve
Yeah, forgot to mention. I did prime the M/C before fitting the brake line.
Also, fluid is pushed through. It does comes out of the bleed nipples when opening them. However, it comes out
much faster on the antidive bleed nipples than on the caliper nipples. Don't know if it gives any clue to the problem?
You seem to know what you're doing, and your described bleeding process should work, but it hasn't :-(
An alternate method is to use a syringe with a tube onto the bleed nipple and push fluid up from the bottom.
It helps to put a couple of turns of teflon tape around the bleed nipple so it doesn't leak air into the system.
Start from the furthest nipple from the master, that would be the Left A-D unit and then the Right A-D unit.
Watch the master cylinder so it doesn't overflow.
This should fill the system and displace any air. Then see if its all working.
IF there is still a bit of cushion, bleed normally to evacuate the last of the air.
Arnie
Wouldn't I need to empty the system first to use the syringe trick?
If I do it now - with a system full of brake fluid - wouldn't I just be pushing all the existing fluid (and air bubbles) out of the system before the "air free" fluid from the syringe can fill the system? Or, would it push the existing air bubbles through the existing fulid?
Right/left calipers/antidive units are the same distance from the master, because brake lines on both sides from the t-piece are the same length.
Yes, it will displace the fluid you have in there, but.....
Since all the fluid is new and clean, you can fill the syringe from the master and inject it into the A-D nipple.
And, sorry I haven't had a splitter in my brake system for a long time, so R or L does not matter.
Breakthrough :yahoo:
It has now been sitting for some hours and I just went out and applied the brake. I have pressure :yes:
Doing some googling it seems that my problem was aerated brake fluid (tiny air bubbles, e.g. caused by the canister being shaked). It is recommended to leave the fluid for some hours to settle to get rid of these microscopic bubbles...
So, now it is hopefully just a matter of doing the old standard bleed routine.
Thank you for your suggestions. I will definitely consider the syringe method next time I do it.
Should I ask WHY you shook the can? :mad:
Glad its working for you now.
Quote from: Arnie on September 05, 2015, 11:26:02 AM
Should I ask WHY you shook the can? :mad:
Glad its working for you now.
You may ask :yes: because I didn't.
Maybe the guy in the shop did, or I drove a little too "fresh" when driving home from the shop :blum2:
Quote from: 4everFJ on September 05, 2015, 11:23:24 AMBreakthrough :yahoo: It has now been sitting for some hours and I just went out and applied the brake. I have pressure :yes: So, now it is hopefully just a matter of doing the old standard bleed routine. Thank you for your suggestions. I will definitely consider the syringe method next time I do it.
4ever,
You should know, at the end of the session, pull the brake lever all the way to the grip, and tie it there with a strap or bungee overnight. Screw the lid on the master cylinder, and cap the brake fluid container, to keep water vapor out (important!). In the morning, first thing, take the lid off the master cylinder, so you can watch what happens. Untie the brake lever and let it out slowly, then work the lever several times, slowly. If any air bubbles come up, repeat this process each night until you get no air bubbles. One or two nights should do the trick. In between times, you can bleed the brakes normally. These two methods should get things right for you. The same tie-back trick works when bleeding the clutch hydraulics, as well.
Cheers,
Red
...or get a Mity Vac
Quote from: Pat Conlon on September 05, 2015, 12:40:58 PM
...or get a Mity Vac
I am strange that way... :crazy:
I always try to fix things with minimum tools. Probably a thing from my youth where I drove highly modified mopeds and didn't have any money to buy tools....
No worries, the good news is that you don't have an ABS equipped FJ which has about 20 feet of hydraulic line...good luck bleeding that without a vacuum pump.
The Master says:
"When sitting, just sit."
Sometimes, removing yourself from the problem provides insight.
Or, ask the FJOC. The answers are here.
You need only seek.