tangerineowl

Have watched a AJ The Bike Guy vid, where he is using a screwdriver to pry out the boot. ( This is the rubber part that has Shimano FH-6400 written on it).

Have tried a couple of fine edges to try and push down in between the slight gap there, but the boot isn't budging up and out. I don't want to go to town and start hacking/digging into this rubber/gap just yet.

Would leaving the hub in a hot environment for a while shrink the rubber a smidge, and allow for an easier removal with a screwdriver or similar fine edge?

Any other tricks?

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mpetry912 

do you absolutely need to remove it ?

use the widest prying tool that you can get in there. Kitchen butter knife maybe

/markp

Crankycrank

You could pour some boiling water over the seal and hope it helps but best to just leave it in place if it doesn't come out easily. If you're determined to remove the seal check and make sure you can find a replacement first if it gets damaged. Been a long time since I worked on one of the 6400 hubs but if I recall it was also easy to damage the freehub body axle seal and replacements may be hard/impossible to find so leave it in place if you can. Part number list. EV-FH-6400-0838B.pdf (shimano.com)
Just did a quick search for the left seal and found this place. Not cheap after paying for shipping from the UK but look below for a list of other hubs that use the same seal and you may have better luck with that info. Shimano 600 Ultegra FH-6400 Left Hand Seal Ring (sjscycles.co.uk)

Iride01 

Push it out from the other side. Is this the hub body or on the non-drive side? On some you can use the axle to do that. If this is in the free hub body, then pull the free hub off first. Though some models don't expose enough of the backside to let you do this.

Andrew R Stewart 

Rubber usually expands with heat, not contracts. But it also gets more pliable. I would try to leave the dust cap (I think that's what is in question) in place and clean around it best possible. Some plastic dust caps have had a molded lip that engaged a shallow groove to stay put. Removing these dust caps can damage this lip and might cause the dust cap to not stay put. Andy

grumpus

It's "RJ the bike guy". To remove those dust caps, easiest is to remove the axle first, then you can get a wide flat screwdriver under the inside edge. Rest something like a piece of wood on the hub flange as a fulcrum to lever against, and work around the hub prying a little at a time.

tangerineowl

Thanks everyone for the pointers.

I'll give these a shot.

icemilkcoffee 

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