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Discussion Starter #1
So last weekend I had my RR brake line split on the track. This weekend I replaced the lines with SS ones and bled all (including the clutch, and front calipers upside down). Pedal is still spongy and often will travel all the way to the floor. The reservoir level got pretty low and I'm afraid air got in the system.

Is it worth bleeding the lines again? Do I need to just bench bleed and/or is it a problem in the ABS unit? Has anyone bench bled an Elise MC?

Thanks,
Shawn
'05 Elise
 

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Yes, bleed the brake lines AND the clutch line (under the car by the oil filter). They share the common master cylinder. If you didn't get into the ABS mode, you probably don't have air in the ABS module. If you do, I heard you need a Lotus proprietary computer to open the ABS channels. :eek: I don't know that for a fact, though.
 

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The clutch master cylinder feed is above the min mark mark on the BF reservoir. Make sure the fluid level stays above this feed port while bleeding the clutch portion of the system.

Occum's Razor dictates that you still have air in the brake system and you should be able to bleed it out. The entire system doesn't hold much fluid, less than 500ml IIRC. It may take you a number of bleed cycles to get 'er done. You might consider using a totally clean bleeder bottle and recycle 500ml of fresh fluid through until you have the system fully bled. Then either leave that fluid in or push a couple hundred more ml of fresh fresh fluid through (to placate any doomsayers).

Also, lightly tap on the lines and calipers while you're bleeding with you hands (or lightly with a rubber mallet) to help dislodge any stubborn lil' bubbles that maybe clinging on to dear life in there.

I prefer to use the suck-n-blow method of both a Motive pressure bleeder umped up to 10 psi) at the reservoir and a vacuum bleeder at the calipers / clutch slave.

At some point, I'll likely drill and tap the inboard side of the front calipers to accept BF lines and add bleeder screws to where the stock lines enter the calipers, tho I do tend to think that Suck-N-Blow+Pump method moves the fluid with enough velocity to get any trapped bubbles thoroughly out of the nooks & crannies.
 

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You have an air bubble into the oil line and/or the ABS unit. Bleed the clutch is totally useless, you lose time unnecessarily.

Bleed the AP calipers is very difficult, you can't do it only from the bleed screws because still remains an air bubble in the internal piston. There are two possibilities: disassemble the calipers and flip, or just let the air out by loosening the hose.

In any case, forget any pressure or vacuum bleeders: the the brake pedal is all you need.

First, you must understand if the master cylinder is still good: to do that, press it 4 or 5 times and hold. If it falls slowly, you've damaged the o-ring seals, otherwise it's ok and you only have an air problem.

To bleed the brake line, you have to be in two: one into the car and one at the calipers. Find a friend with a muscular leg because it will have to press at least 200 times the pedal :D

Your friend must pump three times and holds the pedal: at this point you have to loosen the tube on the inner piston and let the air/oil flow out.
Do this 4-5 times, then repeat the process with the outer screw.

Repeat this for all the calipers. On the Brembo (rear) calipers don't need to loosen the tube, you can only use the bleed screw.

P.s.: pay attention to oil, because it's corrosive. use water to clean.
 

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Discussion Starter #5
Thanks for the suggestions, Frank. I bled it a couple times and activated the ABS before bleeding once more and it seems to be good now. The pedal feels about like it did prior to the stainless lines, I was hoping they would firm it up a little.
 
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