Flush out brake lines/pipes

[middie]

Middie's 1500 motor has been dropped off at the engineers to be boiled/pickled, so now I can start on the engine bay and brakes.

I have new wheel cylinders and linings for the back wheels, and new disk pads for the front. What I would like to do is flush out any "gunk" which is inside the old brake lines before filling with new Dot4.

Any suggestions on how to go about this, and what to use for the flushing?

Wazza

 

[DrEntropy]

Denatured alcohol as a flush, plenty of compressed air too.

 

[JPSmit]

make sure you change all the rubber hoses on the brake lines too - and, take the "splitter" apart - that which directs the brake fluid, it will be dirty. trust me

 

[DrEntropy]

 

[nomad]

I used a large disposable syringe from a vet to force alcohol into the lines then compressed air to blow thru. Several times till no sign of oiley substance before converting to Dot 5.

Kurt.

 

[smaceng]

How about brake cleaner and then dry compressed air?

 

[HAN8L1965]

Somewhere I read that the denatured alcohol must be used as a final flush before going to DOT5. I would say it has to do with proper drying and a very clean surface that does not react with the DOT5?

Mark

 

[DrEntropy]

We've never had an issue in 30+ years using denatured alcohol and 100 PSI air as a "chaser". No matter what fluid went into the system next. Just be THOROUGH with the cleaning.

 

[middie]

I was under the impression that Dot 5 may not have been the best fluid to put in the lines. Something about the silicon?????

 

[JPSmit]

I use it - works great doesn't eat paint

 

[Sarastro]

I was under the impression that Dot 5 may not have been the best fluid to put in the lines. Something about the silicon?????

It's fine, just don't mix it with DOT3/4.

My only worry about DOT5 is that some pimply teenager in a Jiffy Lube somewhere might add DOT3/4 to it, even if you tell him not to.

 

[elrey]

Clear the lines with denatured alcohol and plenty o air, refresh the three hoses, refill, bleed, bleed again. Then celebrate. -- elrey

 

[Guest]

Yeah but only if you let them touch it.

 

[middie]

Thanks for all the advice, just one more question if I may? what is the difference between a UK master cylinder setup and a US setup????

The area where I need to reinstall the master cylinder to convert to RHD has a large circular hole closed with a rubber plug, while the US side has a rectangular area cut out.