Gelled Brake Fluid

[ScottB]

A little history first, and a confession. When I purchassed my 2000 R1100RT it had 39000km's plus change on the clock. It had the stamp in the service manual that the 40000km major service had been done.There are stamps in the book for all major servicing prior to my ownership.

Now the confession,I flushed the brake fluid for the first time yesterday, 17000km's later.This over about 2.5 years.

The front master cylinder was nearly full of a milky gell like substance. I was able to clean this out and flushed nearly a whole bottle of Dot 4 brake fluid through the system. This went fine and the lever feels normal. I have not ridden the bike yet as I am doing some other servicing. The rear resevoir had a very small amount of the same substance in it.

Any ideas as to what has caused this? Could it be that someone has used incompatible brake fluids? I have been working on vehicles my whole life and have seen some pretty nasty looking brake fluid but nothing like this. My intention is to ride the bike a month or so and then do another flush. Thanks for any help or advice.

[Mike T]

It's possible that water got into you brake system from using a power washer or some other way. I had this happen to my SUV after I powerwashed the engine. I replaced all the brake fluid and bleed the brakes and all was fine. Bleeding the brakes again in month or so is a good idea.

[T__]

A little history first, and a confession. When I purchassed my 2000 R1100RT it had 39000km's plus change on the clock. It had the stamp in the service manual that the 40000km major service had been done.There are stamps in the book for all major servicing prior to my ownership.

Now the confession,I flushed the brake fluid for the first time yesterday, 17000km's later.This over about 2.5 years.

The front master cylinder was nearly full of a milky gell like substance. I was able to clean this out and flushed nearly a whole bottle of Dot 4 brake fluid through the system. This went fine and the lever feels normal. I have not ridden the bike yet as I am doing some other servicing. The rear resevoir had a very small amount of the same substance in it.

Any ideas as to what has caused this? Could it be that someone has used incompatible brake fluids? I have been working on vehicles my whole life and have seen some pretty nasty looking brake fluid but nothing like this. My intention is to ride the bike a month or so and then do another flush. Thanks for any help or advice.

 

DOT 3 or 4 brake fluid can jell over time as it is Glycol based.. The milky in your fluid is probably moisture but the jelling could be anything from old proper brake fluid, or possibly some silicone based fluid might have been intermixed.. Even a little oil in the container used to add brake fluid can contaminate the brake fluid & cause jelling..

 

Remove ALL that jelled fluid you can get out as that stuff doesn’t bleed through very easily on it’s own..

 

If your caliper pistons are not sticking & your master cylinder pistons are smooth traveling in their bores I doubt that jelling has hurt much.. After a good bleeding & the proper DOT 4 added make sure the brakes work properly & nothing is sticky or the brakes don’t drag upon release. If any doubt in their integrity pull the entire brake system apart & install new rubber parts..

 

Twisty

[ScottB]

I am not shy about wash water on the bike, but never ever use a preasure washer of any kind.

[ScottB]

This is what I did, I cleaned all the gell and dirty fluid from the resevoir and flushed alot of fluid through. I even bled at the ABS unit which is not really required unless you have air in the system.

The master was not smooth when I began but is now working perfectly. There is no seaping from any of the bores right now and there is no hanging up of the calipers.

I had just never seen this before and was concerned at what I found.

[E30TECH]

I would consider flushing again at 1/2 the recommended interval. There is a lot of 'dead' area in the calipers where one flushing may not get all the gunk out.

[HRminneapolis]

the PO of my Honda never changed fluids, the brake fluid was like pale yellow jello. Ran about a pint of fluid thru front and rear system...all is well 3 years later...but it's about time for my next fluid change...hygroscopic...

[ScottB]

Thanks all, this makes me feel better to know that this is not a unique situation. My own fault to as I knew that the fluid flush was way overdue. Silly because I am usually really good about maintenance, I even help out others less mechanically inclined at every oportunity.