Has anyone ever ble...
 

[Closed] Has anyone ever bled a brake with the wrong fluid?

 JonR
Posts: 0
Free Member
Topic starter
 

I need to assemble a hayes brake but I can't be arsed to buy dot 4 fluid for it so I thought I might use shimano hydraulic fluid.

Has anyone else ever done something similar this to catastrophic effect or is one hydraulic fluid pretty much like another?


 
Posted : 17/02/2010 4:30 pm
Posts: 173
Free Member
 

Don't do it!

The other way round is worse (DOT fluid into a mineral oil brake) but it's still pretty likely that the wrong fluid will trash your seals.


 
Posted : 17/02/2010 4:34 pm
 br
Posts: 18125
Free Member
 

don't worry about, and while you're at it don't waste the shimano fluid - use water instead


 
Posted : 17/02/2010 4:35 pm
 JonR
Posts: 0
Free Member
Topic starter
 

I always new dot 4 was corrosive but shimano fluid seems pretty stable so I thought it would probably work. Still I like the water idea, I think I'll go with that.


 
Posted : 17/02/2010 4:38 pm
 cp
Posts: 8962
Full Member
 

shimano is a mineral oil, DOT is a completely different make up. Seals etc... prob wont like different fluids.


 
Posted : 17/02/2010 4:40 pm
Posts: 20601
Full Member
 

Wrong fluid usually wrecks the seals, voids the warranty and requires a complete total clean and rebuild, it's not worth it!


 
Posted : 17/02/2010 4:57 pm
Posts: 9
Free Member
 

Good troll JonR!


 
Posted : 17/02/2010 5:12 pm
Posts: 39669
Free Member
 

i remember opening up a customers hope mono mini once who brought it in complaining of it sticking badly having very recently been bled by another shop

Turns out the other nameless local shop stuck in shimano fluid - noticable as soon as it was opened.

So i wouldnt recommend it , there is a reason they reccomend a particular fluid ....


 
Posted : 17/02/2010 5:33 pm
 Olly
Posts: 5262
Full Member
 

i asked this question, as mineral oil is not as corrosive to work with as dot and wanted to put it in my nines, and got some pictures posted of a test someone had done.
a few hours and the seals will be shot and ruined.

water will work fine!
just dont get the brakes over 100degrees (ie: dont brake)

i hear veg oil is ok too.....
temporarily though.


 
Posted : 17/02/2010 5:45 pm
Posts: 5559
Free Member
 

no it will be fine I run my diesle on petrol as it is cheaper.
Water wont work not viscous enough but try veg oil


 
Posted : 17/02/2010 5:45 pm
Posts: 9058
Free Member
 

DOT 4 and DOT 5 are interchangable, would try the Shimano stuff though.

Know of someone who used water as a trail-side bodge after ripping the hose off a Magura HS33, worked so well he left it like that.


 
Posted : 17/02/2010 8:01 pm
 tron
Posts: 0
Free Member
 

Water will work, but water screws up DOT 4 and 5.1 by reducing the boiling point. You'll find it difficult to guarantee that all of it's out, so you'll have to bleed through and waste a lot of brake fluid. Why not just assemble it and bleed later? Normal car or motorbike DOT fluid is fine, and easy to get.

DOT 5 is [b]NOT[/b] interchangeable with other DOT fluids - it's silicone based, and again, screws up seals if the system isn't designed for it. DOT 4 and 5.1 absorb water, reducing the boiling point of the fluid slightly. DOT 5 is not miscible with water, so any water in the system finds its way to the lowest point - the caliper - and boils somewhere around its normal boiling point, which isn't good.


 
Posted : 17/02/2010 8:14 pm
Posts: 9
Free Member
 

So DOT 5 and DOT 5.1 are not the same and should not be mixed?


 
Posted : 17/02/2010 8:23 pm
Posts: 3834
Free Member
 

DOT 3, DOT 4 and DOT 5.1 are similar fluids and can safely be mixed with each other.

DOT 5 is totally different and must not be mixed with anything except more DOT 5


 
Posted : 17/02/2010 8:30 pm
Posts: 0
Free Member
 

I bled a set of HS33's with olive oil once!!


 
Posted : 17/02/2010 9:04 pm
Posts: 9058
Free Member
 

EDIT. Meant to say 'wouldn't' above, not 'would.' Hope you have not followed my advice...


 
Posted : 17/02/2010 9:06 pm
Posts: 0
Free Member
 

> Meant to say 'wouldn't' above, not 'would.' Hope you have not followed my advice

You also stated that DOT 4 and 5 are interchangeable, which is incorrect ๐Ÿ™‚


 
Posted : 17/02/2010 9:09 pm
 JonR
Posts: 0
Free Member
Topic starter
 

Good troll JonR!

๐Ÿ™„

I bled a set of HS33's with olive oil once!!

I'd heard this could be done but I thought it was an urban myth. Hope they worked okay.


 
Posted : 18/02/2010 9:26 am
Posts: 5
Free Member
 

Or you could just buy some dot fluid?


 
Posted : 18/02/2010 9:41 am
Posts: 0
Free Member
 

It was on an old trials bike of mine. We just did it for a giggle. Felt ok, not quite as responsive if anything. No idea how it will deal with heat as you dont really get much heat build up riding trials. Flushed it back through with proper fluid the next day.


 
Posted : 18/02/2010 10:16 am
Posts: 0
Free Member
 

Goog off here once got half way round the Gap road and had to top his brakes up with chain oil as they were pulling to the bars. I think he said it trashed his seals though. They were hopes, btw.


 
Posted : 18/02/2010 10:30 am
Posts: 0
Free Member
 

Noticed my front brake (Shimano) had lost fluid at went spongy the beginning of a long ride last year starting a long way from home or a bike shop (with any oil anyway) so got some sunflower oil from a local shop. topped up and bled them on the side of the trail. the remainder of the litre of oil (about 995ml ๐Ÿ˜• ) was dropped of in the next bin

worked perfectly 8)

In fact I ended up leaving it in there for about 6 months before I bothered to bleed 'em and put the proper stuff in, only did it 'cos I felt I should!
They were still working 100%

so not a myth at all

wouldn't have done it with Dot 4 brakes though


 
Posted : 18/02/2010 10:31 am