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Discussion Starter #1
So every year since 2004 I have done an annual service on the Elise. Each year I change; engine oil, tranny fluid, coolant, brake and clutch fluid, clean the air filter and other general maintenance.

This week I did my usual changing of the brake and clutch fluid by pumping out the reservoir and adding new fluid, then corner by corner I used a brake bleed vacuum pump to draw the old fluid through while keeping the reservoir full. Test drove it and the brakes are great as always. Then I did the same with the clutch from underneath and got my usual jar of old fluid until new fluid was coming through. Much to my surprise I got in the car to move it off the ramps and the clutch pedal went to the floor with no resistance.

Figuring something went wrong I did the old method of pump, release, close, pump, expecting to get a clean bleed. Although I seem to be getting a clean stream of fluid at the clutch bleed port when I close the nipple there is no resistance and no clutch actuation, almost as if the clutch pedal is not connected to the master (but it is).

WTF???
 

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Probably lots of air got in. Try doing a gravity bleed to get the air out.
 

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Discussion Starter #3
I would buy that if the reservoir got low, it never did. I am baffled :shrug:
 

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This happened to me after bleeding my clutch at the track. Re-bleed the system and it was fine. Clearly, somehow I got air in the system.
 

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Occum's Razor dictates that you got air in the system, regardless of if you didn't see the reservoir get low.

Fact is that the fitting for the clutch master is pretty high up on the reservoir and that it doesn't take much air AT ALL to render the clutch pedal feeling as if it were "disconnected." I'm willing to put some $ on it.

I bet if you bleed the clutch circuit a couple more times, being über-diligent to keep the fluid above the clutch circuit fitting, that it will "miraculously" fix itself! ;)
 

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Discussion Starter #6
My next move will be to fill it to the brim and bleed again, crossing fingers......
 

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If the other person let up on the clutch pedal, before you closed the valve on the clutch, it WILL suck air in. Pressure systems, such as the sector111 v2 bleeder, prevents the "clutch person's" error from causing this problem.
 

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If the other person let up on the clutch pedal, before you closed the valve on the clutch, it WILL suck air in. Pressure systems, such as the sector111 v2 bleeder, prevents the "clutch person's" error from causing this problem.
Read "I used a brake bleed vacuum pump to draw the old fluid through while keeping the reservoir full."

Where do you get the information that someone was pumping :shrug:
 

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sorry, mis-read, there is more than one way to skin a cat.
 

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Discussion Starter #11
No your both right. I did the vacuum pump method first, the way I usually do it. As an attempt to fix the situation I had a friend pump while I actuated the valve, pretty sure he did it right.
 

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Discussion Starter #12
I never noticed it, but the pickup line for the clutch is above the min line! What &#[email protected] for brains would do such a thing? I see it being above the brakes for them to have priority but this is nuts. So in the past I just got lucky by keeping it at the max line, my helper was doing just what I asked, keeping it above the line, and being experienced in bleeding brakes as I am just assumed that the min line was the line we were talking about. Fixed through a nice slow gravity bleed.
 

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I never noticed it, but the pickup line for the clutch is above the min line! What &#[email protected] for brains would do such a thing? I see it being above the brakes for them to have priority but this is nuts. ...


In answer to your question about why... if the clutch master or slave fails and leaks all its fluid... it can only drop the reservoir halfway; leaving enough fluid for the brakes to work properly even if the clutch does not.
 

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Discussion Starter #15
Yeah, that is pretty much exactly what I said as to why. But put the frickin min line above both draw points!
 

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Yeah, that is pretty much exactly what I said as to why. But put the frickin min line above both draw points!
Because it *is* the min line for the braking system. Keep in mind that the reservoir is *not* a part that was designed by Lotus... IIRC it is a standard GM brake reservoir.
 

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Discussion Starter #17
Acknowledged, but for &$#@sake label it for the task it does, clutch and brakes. And maybe do the bare minimum of what I did, place a label to mark the true low line (it took me 3 min).
 
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