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Discussion Starter #1
I think I might have introduced some air into my brake line when I diy the brake bleed this weekend. I end up with a mushy brake paddle that goes to the floor.

I tried bleeding again with both the pressure bleed and "helpful assistant" in the driver seat, and got some more air out of the line. The brake paddle feel is still mushy, but better.

I suspect that I now have air trapped in the front caliper. I searched the forum and noticed that front caliper will need to be flipped, but I cannot find any directions on how to do that. Can anyone help me with some more direction on how to?
 

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To "flip the calipers" you need to do just that...

The fluid enters the caliper at the top of the inside of the caliper. There is a tube that connects the bottom of the inside to the bottom of the outside of the caliper, and the normal bleed screw at the top of the outside of the caliper. And air in the piston areas of the calipers will "float" to the top. This is bleed out via the bleed nipple on the outside, but unfortunately, any air trapped on the inside half of the caliper can't exit the caliper as the "exit" is on the bottom.

So, what you have to do is to unbolt the caliper from it's bracket, sick a hunk of wood or something similar in between the pistons/brake pads (to prevent them from moving out of the piston bores). Then, holding the caliper upside down (so that the inlet hose and bleed screws are on the bottom and the tube connecting the sides is at the top, continue to bleed the caliper. This will move the air from the inside of the caliper through the tube to the outside of the caliper (where it will be trapped). Then, tun the caliper right side up (you can mount it now if you want to), and continue to bleed. Since the air has been moved "up" through the "bottom" of the caliper to the outside half, as you open the bleed screw (and continue bleeding), the air will be vented out the (proper) top and hopefully all the air will be removed from the system.

Note that there may still be air trapped in the ABS, and to get that out, you need the Lotus Scan Tool to put the ABS into "bleed mode" (which cycles the various valves open and closed) to bleed the ABS.
 

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Discussion Starter #3
It worked! I think...

So I flipped the caliper up, but I did not get any more air out, however, when the caliper is horizontally, a ton, I mean "A LOT" of air just keep on coming out, I continue to tap on the caliper and the rubber brake lines, and more air came out. So now the braking is better, but I still don't think it is as good as before. (I honestly don't remember how it was before though)

I don't understand how the air got in there in the first place. The master cylinder was never dry, because I used pressure bleeder.

I guess now I will just drive it, and bleed it again when I change my engine oil next time. Maybe I will try to activate the ABS to see if I can push some more air into the front caliper "loop area".
 

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Discussion Starter #4
2 additional questions

1. Does the Elise brake paddle easy to hit the floor? I mean when the car is stationary, I can step on the brake paddle, and with enough force it will hit the floor. Also when the engine is not running, I can hit the floor easily after pumping out of the vacuum a few times. I don't remember nor never tried these before I changed the brake fluid, so I don't know if there behaviors are normal.

2. Also, if I do have air in ABS, will the brake effort be diminished even though I am not activating ABS. And will I be able to push the air out of the ABS and into the "loop" between pistons in the front calipers?
 
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