Dot 5 Silicone brake fluid
Discussion
I put a half inch of Dot 4 into my E type's reservoirs before finding out that it may have Dot 5 in it. Obviously the 2 don't mix so I'm planning on syphoning out the reservoir carefully hoping that the dot 4 won't have gone in to the system and topping back up with dot 5.
Is there any way I can tell what is actually in the car? Should I replace it all anyway?
What do we think about Dot 5? I've read a lot about it but you guys have the experience.
Many thanks in advance
Is there any way I can tell what is actually in the car? Should I replace it all anyway?
What do we think about Dot 5? I've read a lot about it but you guys have the experience.
Many thanks in advance
It'd be a bit difficult to tell unless you can do some chemical analysis. Simply measuring the densities might not work too well, as absorbance of moisture form the air will alter that anyway.
In any case, if the brake fluid hasnt been change din 2-3 years, flush it through with your preferred grade and brand of brake fluid.
(or, as I do, pay someone with the right tools to make the job easy to do it)
In any case, if the brake fluid hasnt been change din 2-3 years, flush it through with your preferred grade and brand of brake fluid.
(or, as I do, pay someone with the right tools to make the job easy to do it)
Isn't dot 5 typically coloured so that it can be easily identified?
If it's come from the states, it's potentially dot 5 as for some unfathomable reason they seem too like it.
First things first, take the dot 4 out as best you can.
Bleed a bit out of one of the calipers (your new fluid can not get down there unless you flush through) and try mixing it with fresh dot 4 in a jar - see if it's miscible or it separates - this will tell you what you have.
If original was dot 5, do the best you can to remove every drop of top-up out the m/c and then reverse bleed if poss - push more dot 5 through the calipers and keep removing from the m/c. This will minimise the amount of the brake system that the incorrect fluid comes into contact with, in particular any rubber seals in the calipers or rubber flexi hoses.
Unfortunately a dot 5 system is best off staying dot 5. Don't try and flush and change
If it's come from the states, it's potentially dot 5 as for some unfathomable reason they seem too like it.
First things first, take the dot 4 out as best you can.
Bleed a bit out of one of the calipers (your new fluid can not get down there unless you flush through) and try mixing it with fresh dot 4 in a jar - see if it's miscible or it separates - this will tell you what you have.
If original was dot 5, do the best you can to remove every drop of top-up out the m/c and then reverse bleed if poss - push more dot 5 through the calipers and keep removing from the m/c. This will minimise the amount of the brake system that the incorrect fluid comes into contact with, in particular any rubber seals in the calipers or rubber flexi hoses.
Unfortunately a dot 5 system is best off staying dot 5. Don't try and flush and change
Edited by skinny on Thursday 17th October 11:04
Just a thought here. If you remove as much fluid as possible from the MC reservoir, you could then push back caliper pistons to force more fluid back from the pipework to the reservoir and drain that too.
If dual circuit, ensure that both circuits are pushed back. Oh and don't forget to pump the pedal directly after refilling to push those pistons out.
If dual circuit, ensure that both circuits are pushed back. Oh and don't forget to pump the pedal directly after refilling to push those pistons out.
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