LouieM

See message above.

OldKarz

Blk63Vette

Hello

Ok I am going to take a sh*t in the apple pie...I dont use silicone fluid ..I bleed my brake system every year with "standard" brake fluid...

First step use a turkey baster to remove all brake fluid from master cylinder..Then put new fluid in...

Use my trusty mighty vac and flush out the system..Takes my longer to take off the wheels....Then to bleed the system..No Big deal..

I know a couple of "car collectors".. I mean Duesenburgs and Packards people..high end cars...No of them use Silicone brake fluid.. They are older gentleman..I guess the old school stuff rubbed off on me..I dont use it..

I guess it comes down to preference..I had standard brake fluid in my 1994 Toyota truck and have never replaced the master cylinder or brake cylinders on the truck..It has over 330k on it..

Of course I dont mind bleeding the brake fluid every year..Standard Brake fluid is cheap..

Plus I can inspect brake system see if everything ok...

I found and original master cylinder and had it rebuilt by White Post (incrediable turn around time less than a week)..They do not reccomend silicone brake fluid.. In fact, I think they will void warranty on rebuild if you use it...

If you do convert over to silicone make sure you DO NOT mix the two together.

Good luck in whatever you do...

KS69Coupe

I changed from DOT 3 standard to DOT 5 silicone because DOT 3 eats paint. If you have a leak, you have a problem if it gets on the paint and you'll be dealing with more than just brake fluid. I've been running DOT 5 silicone for awhile and no issues, no problems.

chris ritchie

I can't tell you the number of times I've spilled or splashed brake fluid. I'm pretty careful. But I'm a shade tree mechanic. I don't do this for a living. Thank God I switched to DOT5 many years ago.

QIK59

Hi Blk63,
I am just getting ready to replace the rear cylinders and rebuild the fronts on my '59.

How did you use the Mity Vac to flush your system - did you you suck through the bleeders or as I'm starting to think maybe I will suck right off the brake lines when the cylinders are off.

Thank you,
Jerry

Blk63Vette

Jerry extremely simple no longer need another person to help you bleed the brakes.. Simply put the hose on the bleed screw crack it open and pump the lever...Sucks the old brake fluid right out of the lines...This works GREAT...If you dont have one..You need to go buy one..

QIK59

Thanks Blk,
Oh no I have a Mity Vac - a good one : when they were all metal.
Although I forgot / never thought about using it to bleed the brakes.

Yeah I think I will use it initially to flush the line after I remove each wheel cylinder - that way won't suck any crud into the new wheel cylinders.
Then I'll use it to bleed the cylinders after they are installed - my wife is away / can't help LOL !

Brake fluid is cheap - got a bunch of VW Dot 3 or 4 ? at a swap meet Ha Ha.
I drive my car on trips need to keep things simple.

Jerry

Plasticman

Make sure you are sucking the fluid into a catch bottle (with the vacuum attachment lid) located between the bleeder and the Mity Vac, and not directly through the Mity Vac! Brake fluid in the Mity Vac will ruin it quickly.

Also, do not use a high vacuum. In most cases, high vacuum (over 10 inches, and sometimes as low as 5 inches) will start drawing air past the caliper or wheel cylinder (or even worse, the master cylinder) lip seals, causing air to be constantly drawn into the brakes.

And you may want to put some sealer (plumbers pipe dope works well here) on the threads of each bleeder screw before bleeding. Air will be sucked down the screw threads, and will look just like air in brake lines.

The use of clear tubing is useful in seeing air escaping from the bleeders, and the color / condition of the brake fluid.

Plasticman

QIK59

Yeah gotcha ya there Plasticman - good point !

Thank you for reminding me - I mostly use it for vacuum testing things.

Although I had thought about being able to watch the colour etc of the fluid.

Jerry

sub006

I switched to silicone over 25 years ago, no problems. Then again, my car has drum brakes.

Aussi-66

Ok guys I have a dumb question, when flushing with alcohol which type do I use to avoid damaging seals.

MikeM

I would just give it a good flush with air and then shoot the silicone to it. That's what I've always done with no problems.

My objective was always to get any residual water out of the system, residual glycol was second.

Now if you want to be a real expert, take everything apart and wipe it down, rinse three times with alcohol, wiping between rinses, then throw that stuff away and put new seals in it. Oh, and don't forget to change your steel lines. They have likely absorbed some nasty glycol over the years and that stuff will bleed back into your freshly installed silicone. Can't be too careful!

maroon67

Denatured Alcohol

Plasticman

I agree with MikeM. No way would I put alcohol in a brake system (to "flush" it), and expect all the alcohol to come out (and also not potentially damage a seal), without opening everything up. Bleeders are at the top of the calipers and cylinders. How are you going to remove the alcohol sitting in the bottom of them? Blowing air is not going to remove that alcohol without at least removing the calipers or wheel cylinders from their mounts, and tilting them so that the bleeders are pointing downward. Even then I would be concerned with residual alcohol remaining in the system. But I would still undo them at the mounts, and drain and flush with the Silicone fluid.

That was the way we have always done it in several vehicles (that previously had DOT3 fluid), without opening everything up or flushing, without any issues (over a few decades). Maybe I was lucky........or?

Plasticman