guys, i am tearing my hair out here. i have been trying to bleed my front brake for the last 2 hours. i have the service manual and tried it that way. i tried it the old fashioned way with a freind, pumping the lever. i tried it with a hand vac in conjuction with the manual way, tried it with the lever strapped back with the hand vac. i even tried reversing the system and pumping from the caliper up. i have bled brakes on about 100 cars and this very bike once, with success, but i can't figure this out. i can't find any leaks, line is brand new. no fluid or air coming from anywhere, that i can tell.
this is how i got to this point:
i installed new bars. when i removed my oldones, i actually layed the bars on the tank (on a towel) with everythign still connected..the master was turned upside down. i was worried about the brake system getting air, but i knew i had to re bleed anyway. my stock line was too long after installing the new bars. i went to the custom shop and picked up a braided line with 2 new ends and new gasket/washers. installed it all, tighted it all 20 times, and check for leaks 20 more times. could i have messed up my master cylinder somehow. i never dropped it or anything. i am stumped or stupid. i thought for sure pumping it from the bottom would have work. it seemed like it was, lots of air bubling at first. but 2 bottles of dot5 later and still nothing. fluid is moving throught the line, and again, no apparanet leaks from either of the 2 unions. i am so sconfused, and, worse, without my harley. please help!
dan
denver, co
__________________
1998 Superglide SOLD
2007 Street Bob
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I just went though this with my bike last weekend. It took about an hour. I have dual front disc brakes, so it was a total pain trying to get rid of all the air. I started with the left caliper and went to the right, and then back and forth.
Not to insult, but I had my wife squeeze the lever, I would crack the bleed valve, watch the bubbles/fluid, close the valve, release the lever, repeat.
The other alternative I have read about, you already did, pumping from the caliper...as air bubbles rise. I'm assuming you don't have anti-lock brakes, (you haven't upgraded have you?), because you need a high pressure system to properly bleed anti-lock brakes.
My suggestion would be to keep at it, but take a break for a cold one every now and again. You'll either get drunk or get 'em fixed. Let us know how it turns out.
When I look at your handle 98 fxd, I hope that's not what you're putting DOT 5 in. If it is and you didn't switch over prior to this with a complete rebuild, YOU HAVE PROBLEMS!
That should not be dot 5 but possibly 3 or 4 at best, they do not mix. You will have jelly in no time.
If all is cool with the 5 ,after you have bled the calipers good, turn the bars all the way left, then tie your brake lever in the "squeezed" position with a bungee or the like, fill the master cylinder and go to bed. In the morning before you release the lever, tap around the outside of the cylinder and line with a hammer handle and watch inside the cylinder at the bubbles that come up in the fluid and let us know what happens. The DOT 5 is heavier than the previous fluids, this is why you may be having problems. Good night John Boy!
sh$%. yes i have a 98 superglide. everyone told me to use dot 5, hd dealer and custom shop. i didin't replace fluid prior to this event, but the cylinder was completely drained and whatever fluid was in the caliper has been purged in the extensive bleeding process. no gelling at all.
so you are saying, leave the cap off the master over night? i though brake fluid absorbed moisture or something and it was very bad to leave it exposed to the air. or are you saying, turn the wheel, fill the mater, install master cover, and in the morning remove the cover and tap? in retrospect i spent three ours this afternoon bleeding... i must have a leak. there is no way after three hours i would have air? right? ahhhhhh?
thanks guys
edit:
1 hour later. its now 12:30 am. i got it. persistance, like pilot said. continued bleeding fromthe bottom up, but this time, instead of continued pumping, i closed the bleed screw before each pump was finished. no problems. just took her for a test spin. not as much pressure as i'd like, but at least its rideable. new clutch cable arrive in about 10 days, then i will be all set (using the old cable for now)
drag bar price tag:
bars: $42
risers: $64
new risers: (the duece style doesn't fit right) $140 max
grips: kurakyn iso's with t-boss $64
brake line: $34
fittings: $20
dot5: $11
clutch cable: $24
spacers and bolts for speedo mount: $4
time: 2 hours for install, 3 hours to bleed
total= lots. although i really prefer the feel to the sweeping bars that were on there. and it looks a lot cooler too. that massive speedo has to go though. i need some kind of replacment thats small, electric and mounts to the batrs on the inside. anyone have any ideas?
thansk for the help guys... brakes stink! you guys rock!
__________________
1998 Superglide SOLD
2007 Street Bob
>>>>sh$%. yes i have a 98 superglide. everyone told me to use dot 5,
OOOOOOOOOOOh BOY!!!!!!
If the fluid you used was the 5.1 and not the 5 ,you may be ok here, that one is compatible with the others supposedly
Dot 5 will give you a softer handle than 3 or 4 and it doesn't absorb moisture like the others.
Don't know what to tell you here , if you used the 5 , the damage is done (seals etc), ALWAYS consult your manual for the correct info. Dot 3 was used for years and then they switch to 4, they both raise hell with paint and absorb moisture. Along came dot 5 and no more paint hazards and no moisture problems and in 2005, they went back to dot 4 because of the ABS used on cop bikes.
Leave the master cylinder cap on , but not necessarily tightened down all the way.
With all the bleeding you did, it's a crap shoot if you will have serious problems or not, but the way I look at it , ANY brake problems are SERIOUS. Check with a GOOD parts guy and see if they list different seals for calipers and master cylinders for the different years, say 1998 verses 03 or 04, should also tell you something here if they are different part numbers that the different fluids have a bearing on the seals barring any changes in the physical size etc., but the fluids should never be mixed, they have a different base.
I think if it were me, I would disasemble the entire system and flush with a cleaner made for brake systems and replace the seals. JMHO
Do a 'GOOGLE" search and enter Mixing dot 4 and dot 5 brake fluids, see what you bring up!
I hope the following info can help clear up the murky debate about DOT 5 verses DOT 3-4 brake fluids. The important technical issues governing the use of a particular specification brake fluid are as follows:
Fluid compatibility with the brake system rubber, plastic and metal components.
Water absorption and corrosion.
Fluid boiling point and other physical characteristics.
Brake system contamination and sludging.
Additionally, some technical comments will be made about the new brake fluid formulations appearing on the scene.
First of all, it's important to understand the chemical nature of brake fluid. DOT 3 brake fluids are mixtures of glycols and glycol ethers. DOT 4 contains borate esters in addition to what is contained in DOT 3. These brake fluids are somewhat similar to automotive anti-freeze (ethylene glycol) and are not a petroleum fluid. DOT 5 is silicone chemistry.
Fluid Compatibility
Brake system materials must be compatible with the system fluid. Compatibility is determined by chemistry, and no amount of advertising, wishful thinking or rationalizing can change the science of chemical compatibility. Both DOT 3-4 and DOT 5 fluids are compatible with most brake system materials except in the case some silicone rubber external components such as caliper piston boots, which are attacked by silicon fluids and greases.
Water absorption and corrosion
The big bugaboo with DOT 3-4 fluids always cited by silicone fluid advocates is water absorption. DOT 3-4 glycol based fluids, just like ethylene glycol antifreezes, are readily miscible with water. Long term brake system water content tends to reach a maximum of about 3%, which is readily handled by the corrosion inhibitors in the brake fluid formulation. Since the inhibitors are gradually depleted as they do their job, glycol brake fluid, just like anti-freeze, needs to be changed periodically. DOT 5 fluids, not being water miscible, must rely on the silicone (with some corrosion inhibitors) as a barrier film to control corrosion. Water is not absorbed by silicone as in the case of DOT 3-4 fluids, and will remain as a separate globule sinking to the lowest point in the brake system, since it is more dense.
Fluid boiling point
DOT 4 glycol based fluid has a higher boiling point (446F) than DOT 3 (401F), and both fluids will exhibit a reduced boiling point as water content increases. DOT 5 in its pure state offers a higher boiling point (500F) however if water got into the system, and a big globule found its way into a caliper, the water would start to boil at 212F causing a vapor lock condition [possible brake failure]. By contrast, DOT 3 fluid with 3% water content would still exhibit a boiling point of 300F. Silicone fluids also exhibit a 3 times greater propensity to dissolve air and other gasses which can lead to a "spongy pedal" and reduced braking at high altitudes.
DOT 3 and DOT 4 fluids are mutually compatible, the major disadvantage of such a mix being a lowered boiling point. In an emergency, it'll do. Silicone fluid will not mix, but will float on top. From a lubricity standpoint, neither fluids are outstanding, though silicones will exhibit a more stable viscosity index in extreme temperatures, which is why the US Army likes silicone fluids. Since few of us ride at temperatures very much below freezing, let alone at 40 below zero, silicone's low temperature advantage won't be apparent. Neither fluids will reduce stopping distances.
With the advent of ABS systems, the limitations of existing brake fluids have been recognized and the brake fluid manufacturers have been working on formulations with enhanced properties. However, the chosen direction has not been silicone. The only major user of silicone is the US Army. It has recently asked the SAE about a procedure for converting from silicon back to DOT 3-4. If they ever decide to switch, silicone brake fluid will go the way of leaded gas.
I think if it were me, I would disasemble the entire system and flush with a cleaner made for brake systems and replace the seals. JMHO
What seals? inside the caliper? inside the master cylinder? drag? i am not sure i am comfoprtable tearing those items apart. the external seals at the banjo jolts are new, but you prbabaly don't mean those. i pushed a full bottle of dot 5 through the system and discarded it. so i am quite certain that i have purged all the old fluid, in theory i guess there all super small amounts left. anyway, after another quick bleed, my lever has good feel, better than it was before.
thanks for all the info. i will tread lightly for a litte while and see if i develop any problems.
__________________
1998 Superglide SOLD
2007 Street Bob
Seals in the caliper (s), and master cylinder, not the banjo washers.
I only mention this to you because as anal as I am with everything I do, that I probably wouldn't go over 10 MPH or sleep nights until I took care of it But thats ME!
98FXD,
That was a very good and informative article that Grover wrote to you. It has a ton of very good information in it. i don't know that you needed to know the boiling point of the particular fluids but the guy is smart, I'll say that or he reads and copies well one or the other. I would say it's from experience though more than anything.
Now to break it down for you, You are going to need a Service Manual, a Master cylinder and Cliper rebuild kit and probably going to need to change out any of the rubber lines you have effected by entering DOT 5 into a system that would have called for DOT 3 or 4.
It is a royal PIA to rebuild them and you do need to be very very careful as there are springs in there that can take your eye out if you are not careful. The job can be done by about anyone and you can do it if you will just read the service manual and follow the directions to the letter.
Now after you have completely rebuilt the system and flushed out the remaining lines, Before replacing the master cylinder and the caliper the nyou can now use the DOT 5 fluid. Make sure you let the next person down the road who you at some point may sell the bike to that you have swapped the system over to DOT 5 so they don't use DOT 3 or 4 and kill themselves when the fluids do gel up after thye purge it with the wrong fluid.
Be very careful and you won't have any problems doing the rebuild. You have most likely killed any rubber boots, seals, gaskets etc with the mixture of the DOT 5 though and that's why you are not getting any lever. Good luck and be very careful. SpiderJim.
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"Life is to short to dance with ugly people".
"The truth will only hurt once. A lie will hurt you the rest of your life." SpiderJim.
yes, another bleeding problem
