Wrong brake fluid used ??
Thread Starter
|
Seasoned HDF Member
Joined: Apr 2011
Posts: 6,183
Likes: 2,131
From: W. Texas
Wrong brake fluid used ??
Continuation of rear brake kinda hard The brakes are new and was to have been flushed. Yup it was flushed with Dot 3 or 4 come to find out. I`m not sure how big of a deal this might be but on a auto I`d be jumping naked on SOMEBODY BG We used to be a Mitsubishi car dealer and one of the guys used Dot 3 in a H&^5 I can`t remember what model it was but you wanna talk about a mess. IT WAS . Lines look good no kinks that I can find. What I noticed was that with the caliper off I can push the pedal a full stroke, the piston moved. Let pedal up, wait a few seconds and take another push (stroke) Pistons haven`t moved since. 2 more strokes no piston movement. It seems like the m/cyl is not taking fluid on to make a second or 3rd stroke. Reservoir cap off The fluid is clear amber and I ck`d with PO it does have dot 3 or 4 in it. He asked what difference would it make. Ummm Things that make ya go Ummm BG WP
Seasoned HDF Member
Joined: Aug 2007
Posts: 8,195
Likes: 3,085
From: NW AR
Start with flushing what you have. Drain it, run some brake cleaner through it all, disconnect the line at the MC, open the caliper bleeder, hook up an air hose and blow it all clean. Fill with DOT5 and flush a bunch with that. See if it works. If you didn't get a bunch of black stuff (your seals) come out with the flushes and the brakes work, I thinkyou'll be OK, otherwise get some rebuild kits (seals) and rebuild the MC and caliper.
Seasoned HDF Member
Joined: Dec 2010
Posts: 7,736
Likes: 1,524
From: Coromandel Peninsula New Zealand
I have a jar of mixed dot 4 and dot 5, I shake it every week but it hasn't turned to jelly in a year....
I flush with meths when doing a dot swap, works fine :-)
I flush with meths when doing a dot swap, works fine :-)
Thread Starter
|
Seasoned HDF Member
Joined: Apr 2011
Posts: 6,183
Likes: 2,131
From: W. Texas
DR Hess
With the age of the bike I`m gonna get the kits to rebuild the the M/Cyl. and caliper. Get things flushed good and go from there Thank you for your help Sir WP
With the age of the bike I`m gonna get the kits to rebuild the the M/Cyl. and caliper. Get things flushed good and go from there Thank you for your help Sir WP
Grand HDF Member
Joined: May 2008
Posts: 4,324
Likes: 3,571
From: Picayune, Ms.
Difference is the boiling point of the fluids, only thing DOT 4 will do is boil out of the system under constant hard braking. DOT 5 will stay on the job. Thus the reason DOT 5 is used in race cars and airplanes.
DOT 5 won't ruin your paint, DOT3/4 will or maybe.
DOT 5 won't ruin your paint, DOT3/4 will or maybe.
Thread Starter
|
Seasoned HDF Member
Joined: Apr 2011
Posts: 6,183
Likes: 2,131
From: W. Texas
I can count on one hand the number of times I thought mixing dot 3-4 with dot 5 caused a problem in an auto. With a good bit of varying degrees as to severity of problems we thought it caused. I`ll just feel better rebuilding the M Cyl and Caliper and getting it all cleaned up good. I do appreicate your help WP
Tourer
Joined: Apr 2011
Posts: 251
Likes: 0
From: sun valley ca.usa
but you cannot mix 3/4 and 5.... spanner 39 says he has a jar of it mixed with no problems .....I had it in my brakes lines and it was one unholy mess ....jelly everywhere and a hard as rock lever that wouldn't put the brakes on ...had to drain and flush all lines and disassemble all rubber parts to clean/replace even the master and then reload with 3/4
It looked like a jellyfish hab been in my calipers a translucent greenish colour ...after the cleaning and removing all rubbers and cleaning behind them ..it was fine .......
and even race cars are going away from using it as it doesn't work well at all temps just extreme temps
It looked like a jellyfish hab been in my calipers a translucent greenish colour ...after the cleaning and removing all rubbers and cleaning behind them ..it was fine .......
and even race cars are going away from using it as it doesn't work well at all temps just extreme temps
Trending Topics
The difference is dot 3,4 & 5.1 are Glycol Based, DOT 5 is silicone based.
It is so common to find Harley with brakes not working simply because owners have added brake fluid without realising the differences.
A dyna I bought a while ago had this very issue, it can be sorted but does involve stripping the brake system down and cleaning all parts making sure all fluid is out. Then re-assemble and flush with the correct fluid, then bleed.
It is so common to find Harley with brakes not working simply because owners have added brake fluid without realising the differences.
A dyna I bought a while ago had this very issue, it can be sorted but does involve stripping the brake system down and cleaning all parts making sure all fluid is out. Then re-assemble and flush with the correct fluid, then bleed.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider
Verdad Gallardo
The Best and Worst Harley-Davidson Moves of 2025
Verdad Gallardo
Thread Starter
|
Seasoned HDF Member
Joined: Apr 2011
Posts: 6,183
Likes: 2,131
From: W. Texas
Then re-assemble and flush with the correct fluid, then bleed
Dot 5 has not been easily found in my little city. So I`m told and the 2 supply store I ckd with yesterday say they don`t carry it. Ordering for me wasn`t even mentioned. I`ll ck with a couple of indys and a dealer a few miles away. With the age of the bike I`m thinking take things apart and reseal the master cyl and caliper Thank you Sir WP
Dot 5 has not been easily found in my little city. So I`m told and the 2 supply store I ckd with yesterday say they don`t carry it. Ordering for me wasn`t even mentioned. I`ll ck with a couple of indys and a dealer a few miles away. With the age of the bike I`m thinking take things apart and reseal the master cyl and caliper Thank you Sir WP