bigearl91

Just wanted to know what people's suggestion would be when changing out the calipers.

My front driver-side has seized so I am going to do all 4 lines to s/s while I refurb both front calipers. (rears were done last year)

Both calipers will be empty of course so there's going to be loads of air from the new brake lines to the bleeder screw particularly on the fronts.

I have read several of the gravity bleed DIY's and understand what I am to do but it seems primarily that this is for a fluid change.

Will 1 litre of ATE super blue be sufficient when having to completely rebleed every caliper? And is it just going to be quicker to do a traditional bleed to get rid of all the air? is it even possible to gravity bleed when doing this much work?

Cheers
Earl

thomsbrain

Gravity bleed might take a lot longer than usual but should technically still work. I think 1 liter is probably enough if you don't waste a ton. I would not empty and re-fill the reservoir prior to removing the lines (you would normally do that when bleeding). Let the old fluid be the fluid that gets wasted dripping out of the open hard lines while you install the new lines. When you are done installing, then you can top off and bleed with fresh fluid.

That said, you can do a one-man pedal bleed by wedging a breaker bar or other good-length bar between the seat and brake pedal to apply even pressure. That can help get the first big chunk of fluid pushed through so that the rest of the gravity bleed doesn't take so long. I did that when rebuilding calipers (those need a lot of initial fluid to get primed).

Lastly, don't be surprised if you need to bleed again after your first test drive.

bigearl91

I also have a litre of unopened Mobil dot4 so if I lose a ton while changing out the lines I can always fill the system with that then flush through with the ATE, won't be doing this until the 23rd, I'll keep researching for what people have recommended but the bar method sounds like a good idea, being in Scotland the rain can come at any point so if that fails I can get my neighbour a bottle of whiskey and see if he would help me for and hour don't want the fluid exposed to any moisture really.

Cheers
Earl.

RedCelica

When I changed out my lines I ended up using almost 2L on the whole thing. Getting it started was a PITA, but it'll gravity bleed from there. I used a large syringe to get the fluid down to the caliper though to make my job easier.