I bought a pair of XTR M985 levers from that auction site.

Had a look at them last night and one of them the lever does not spring back when pulled and just flops around, this morning the lever did spring back once.

The other lever is fine and springs back when pulled.

If i were to fit and bleed it, is it likely to change anything? Or is it knackered.

This happened to my XTs last year. Something has got into the lever and corroded seals and things and it’s basically unfixable, a bleed won’t sort it.

Argghh. Thanks munrobiker

It might not be the case. It may need a new spring, or the spring may have come loose. If you buy a new replacement lever, it comes with a new spring, I think!

Its worth stripping to check but my guess is its fubar seals knackered from using dot fluid

As its presumably from ebay then return for a refund as its not working unless sold spares or repair

I had the same issue with a pals XTR Race lever a few back, started to stick before a ride then free’d off once it had ‘warmed up’. This happened a couple of times before sticking in for good!
I removed the lever blade, circlip, plunger and hose then had to press the piston out with a drift through the hole to the hose.
Inside the lever was scuffed / scored, even when polished up the piston (with seals removed) was still tight in lever.
Couldn’t see any damage to the piston, my thought was that the lever was slightly bent? I ended up maching the center part of the piston in the lathe, removed about .01mm
Reassembled it all and bled it up and it worked a treat.
To be honest it was bin fodder and a new lever needed, but i just wanted to try and get working again.

my XTR lever did the same. I warrantied it, so not much use in your case.

Totes knackered. It’seems presumably fixable, but I don’t know how you can actually do it without rendering the lever a scratched messy, mess. I bought a ‘spares or repair’ XTR lever from t’bay with exactly the same issue. I managed to take it all apart and free up the piston, but there’s no way I’d realistically be able to put it back together again.

IME Shimano stuff is designed to be expensively disposable.

Send it back for a refund.

The other thing that happens is when you catch the lever falling off the bike and rip the circlip holding the lever in. You can reassemble it but next time it’ll happen all the easier until it’s replace the whole lever time.
The 3 year warranty on XTR stuff makes justifies the extra cost for me: Cassettes fall to pieces (rivet failure) before they wear out and you get a brand new one for free. Ditto sticky brake lever problem (very common).

If you want to have a go at replacing bits on the lever, check out SJS. They’ve saved me ditching kit a few times by having all sorts of random parts for shimano gear.