Flushing Brake Fluid???
Seasoned HDF Member
Joined: Jan 2011
Posts: 157,326
Likes: 56,888
From: Michigan 15 Minutes East Of Hell
I just posted this in another thread on the same subject. Yes you should flush your brake fluid.
Bingo ... We have a winner DOT 5 does NOT absorb moisture. Dot 3 and Dot 4 are hygroscopic ( yes, with a "g" ) which means they can/will absorb moisture. When a system is flushed, cleaned and new fluid ( appropriate type ) added you have removed the moisture from the system. Moisture ( water ) has a much lower boiling point than brake fluid. It is also heavier than the brake fluids which means that it will get to the bottom of the system and be susceptible to evaporation, hence air resulting in a soft/low pedal/lever. Also the moisture can corrode in the system. Always use the appropriate fluid designated by the manufacture. DO NOT USE DOT 5 in ABS systems as it is prone to aeration from the cycles of brake activation from the ABS unit. If you have an old scooter that sits a lot DOT 5 is highly recommended ... just my.02 cents worth
Bingo ... We have a winner DOT 5 does NOT absorb moisture. Dot 3 and Dot 4 are hygroscopic ( yes, with a "g" ) which means they can/will absorb moisture. When a system is flushed, cleaned and new fluid ( appropriate type ) added you have removed the moisture from the system. Moisture ( water ) has a much lower boiling point than brake fluid. It is also heavier than the brake fluids which means that it will get to the bottom of the system and be susceptible to evaporation, hence air resulting in a soft/low pedal/lever. Also the moisture can corrode in the system. Always use the appropriate fluid designated by the manufacture. DO NOT USE DOT 5 in ABS systems as it is prone to aeration from the cycles of brake activation from the ABS unit. If you have an old scooter that sits a lot DOT 5 is highly recommended ... just my.02 cents worth
Road Master
Joined: Dec 2009
Posts: 843
Likes: 43
From: Louisiana
I used to think what ever every time I saw speed bleeders....just bought a set. Damn wish I had done it years ago.
Sure makes bleeding the brakes a simple task!
Steve
Advanced
Joined: Jun 2017
Posts: 71
Likes: 28
From: 71566 Althuette
I'll let you know if it helps as soon as my new tranny got installed.
One more questions to those with the transfer issue: mine was whining mainly in 3rd and 4th gear from the beginning and I had the impression the whining got louder over time. Maybe there is a correlation between the noise and the leaking tranny?
One more questions to those with the transfer issue: mine was whining mainly in 3rd and 4th gear from the beginning and I had the impression the whining got louder over time. Maybe there is a correlation between the noise and the leaking tranny?
Seasoned HDF Member
Joined: Apr 2015
Posts: 10,001
Likes: 5,266
Tourer
Joined: Sep 2009
Posts: 484
Likes: 38
From: DE
I went to order some speed bleeders and see they come in many thread sizes. What does a HD need?
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