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Fri Apr 24, 2015 9:25 pm

On calipers with two bleeder valves what one should you bleed first top or bottom?

Fri Apr 24, 2015 9:49 pm

you only have to bleed the top.

Fri Apr 24, 2015 10:48 pm

They only put two bleeders on so you could put the caliper on either side of the car. Air (bubbles, pockets, whatever) floats to the top; so do as JP said and just worry about bleeding the top bleeder.

Tim

Sun Apr 26, 2015 11:44 am

While I totally agree with johnny and tim's replies here, I recently read an interesting comment in my brown colored type 3 Bentley manual. In the brake section #2, page 13, "The main function of the additional bleeder valve at the bottom of this new-type caliper is to permit old brake fluid to drain completely when the brake fluid is changed. The older-type calipers must be disassembled to drain the fluid from the lower brake fluid passage."
I will admit, I have not performed this method to flush out brake fluid. My norm has been to slowly pump the brake pedal approx. 30x for the rear cylinders and 20x for the fronts. Some may say this many times could possibly damage the master cyl internals, but I try and not bottom out the master cyl.
Hope this helps, Bill.

Sun Apr 26, 2015 3:29 pm

rocker, that makes sense--as far as bleeding.

When I completely bleed the brake system, I just gravity bleed until I see nice, new brake fluid. Then have my daughter do a little pumping and holding while I open and close the bleeder screws for the final bleeds.

I haven't changed out the brake fluid since installing a new front disc conversion, but I will bleed from the bottom screw.

Tim

Mon Apr 27, 2015 6:16 am

So, basically, the lower bleeder is not necessary for only bleeding air out of the brakes. It is used for flushing the brakes. Presumably the hose enters near the top of midpoint of the piston, so any fluid not between the hose inlet and bleeder wouldn't get changed in a brake flush.

I can actually say I've seen the downsides of this on my Father-in-law's cheap chinese knockoff of a honda rebel, front and rear calipers are all dual-piston with the inlet and bleeder right next to eachother. after a while, the brakes were crap and wouldn't get any better after bleeding so he took them apart. Found swamp goo filling the caliper behind the piston. old nasty fluid had never been moved with all his brake bleeding.

Mon Apr 27, 2015 11:31 am

Is this a fixed caliper or a floater?

Does it have one or two cylinders?

Mon Apr 27, 2015 3:10 pm

Well, I'm not a fan of Empi stuff; but their front disc conversion I installed was very well made. It may have been "cheap", but sometimes that's a good thing. cheap and well-made. Now I like that.

Tim