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I have a weird friggin clutch issue that I just can't figure out, after much hypothesizing.

What I have, but only on occasion, is dead travel in the first few inches of pedal travel. The pedal will only have the resistance of the spring in the first part of the travel, then it feels completely normal as its hit resistance. When it does this, the clutch won't release until the pedal is very near the floor. I was fearful last time that I wouldn't be able to shift gears if it went any further. I had no play left when at its worst.

The physical clutch feels completely normal itself. Also the fluid level hasn't changed at all. No leaks. No weird noises. I noticed this the first time, and at its worst, when at Mogfest this year after a mild trail ride. I think it was gradual because it didnt occur to me until getting back to camp. I just took it for a test drive and its back to normal. It has been sitting a couple weeks. I drove it 15 minutes and the pedal didnt vary at all this time.... it feels like it should with hyd resistance within the first 1/2" of travel.

The few guess have been:
AIR, but I doubt this as I've dealt with air many times and this seems very different than any air issue I ever heard of.
WRONG CLUTCH PARTS, two people guess this one but I think if I had the wrong clutch it would never feel normal and Id have other issues.
HEAT- someone said heat may be affecting the hyd line and changing the humidity levels in the fluid as it likely has some water in it. I highly doubt this one but Im open to anything at this point.

The old "replace parts till its fixed" isn't an option for me as its probably $800 to replace everything. Other guesses? And yes, this is on a Steyr, just not a Pinz, but its the same basic set-up.

Flush hydraulics?

If it was me I’d remove and disassemble / clean / inspect / reassemble the master cylinder. it sounds like the piston in the master cylinder is not returning consistently.
Could be the slave cylinder however my first impression from your description would be the master.
Mind you it’s been a few decades since I was an energetic “6076 Equipment Hydraulic/Pneumatic/Structures Mechanic Aircraft Maintenance Ground Support” (quite a mouth full for a job title isn’t it) in the Marines so my diagnosis could be way off.
I do still like to take things apart though and that would be my starting point.

Also inspect the flexible line, make sure it’s not “mushy” and possibly collapsing on its self.

Bleed the system a few times just to make sure...and it doesn't cost much if anything since you probably have fluid lay'n around already. It does sound like the fluid might be bypassing in the master from what you described. Start w/ the easiest(cheapest) and go backwards before you start tearing into.

Roverchef wrote:Start w/ the easiest(cheapest) and go backwards before you start tearing into.

Spoil sport

Well? Enquiring minds want to know!

Thanks for the suggestions but I've done it all. I'm leaning toward the fluid bypassing the seals in the master, but I can't quite understand how it got back to normal after sitting.

As of right now, it works perfectly still. I drove it again and still no issues. I may have to wait till another 4x4 trip where Im working it harder for an hour or more to see if it happens again and go from there. If it occurs then, it must be heat related somehow.

I was just wondering,is there a line that runs next or by something that gets hot on a longer drive? My thought is that something is changing with temperature and not letting the fluid return to m/cyl. I would look close at rubber lines,maybe delaminating on the inside w,hot causing restriction. But then again,if fluid can't go back the clutch would be dis-engaged.... Just a moment of ramble....

i think its worn pressure plate springs or in the pedal assembly itself have you looked at all the moving parts maybe a piece of debris is stuck somewhere.