Bicycle Mechanics - 19mm cone wrenches?

I got a set of older Trek MTB rims from someone and they cleaned up quite nicely on the outside but the slots for the cone wrench are really far apart. I have pairs in 13mm through 16mm and the 16mm looks like it's just a mm short. However, when I took it to the shop to figure out exactly what size, the mechanic told me I needed a 19mm. I can't believe it.

Was this a common size about 10 years ago for wheels with cartridge bearings?

I was able to get one side off using a pair of crescent wrenches but it was a pretty ugly operation. I pried up the seal, flushed out all the dried up grease and put some fresh grease in there and that side is good. But I can tell I'm going to need to get the other side off as well.

The hub says "System 3" on it. I couldn't find much information about them online. The only thing I know is that once cleaned up this set of rims seems like it would be much better than the joytech rims I currently have.

yes, there are (were) some hubs that call for 19mm cone wrenches and they exist. Both Park and Pedros among others make (made?) them. I use a 19mm cone wrench to for the spring tension cam on my old SunTour canti's. If you need one, I have a few new ones in stock and can give you a decent price.

There are very few places on a bike where crescent wrenches (or pliers or Vise Grips) are appropriate. Please take FB up on his offer or get the appropriate tools from somewhere else.

Thanks. I may take you up on your offer if I can't find something local (read: more immediate).

I have a followup question. There is no lock nut, only the cone. The cone itself has the male threads and the axle is actually flush with the outside of the bearing. Once I have removed one of the cones, there is no way to get any purchase to remove the other. After reading a lot of stuff online, I assumed that what I needed to do was punch the axle out from the side with the cone removed. However, with a dowel that was the diameter of the axle and a hammer and substantial force nothing would budge. Was reluctant to bang any harder as I was afraid I would ruin the whole thing.

What am I doing wrong? I don't actually want to remove the axel - I just want to flip up the seal and get new grease in there.

There are very few places on a bike where crescent wrenches (or pliers or Vise Grips) are appropriate. Please take FB up on his offer or get the appropriate tools from somewhere else.

Agreed, but the crescent wrench isn't really the nature of my problem.

I wonder why no one markets an adjustable cone wrench though... I've seen a home-made version, but the cost/time factor really isn't there for me.

"I wonder why no one markets an adjustable cone wrench though"
It is probably very difficult to reconcile adjustability with the need to keep the wrench very thin yet sufficiently rigid as not to "spring" the tool or damage the cone flats.

Well there are 19mm open end cone wrenches ..
FWIW 'cool tool' had a thin jaw adjustable wrench in its folded tool assortment,
wonder what happened to them?

There is no lock nut, only the cone. The cone itself has the male threads and the axle is actually flush with the outside of the bearing. Once I have removed one of the cones, there is no way to get any purchase to remove the other. After reading a lot of stuff online, I assumed that what I needed to do was punch the axle out from the side with the cone removed. However, with a dowel that was the diameter of the axle and a hammer and substantial force nothing would budge. Was reluctant to bang any harder as I was afraid I would ruin the whole thing.

What am I doing wrong? I don't actually want to remove the axel - I just want to flip up the seal and get new grease in there.

What brand/model hub is this? Can you post a picture? Some early Trek MTBs used SunTour XC hubs, which took a special wrench:

http://www.os2.dhs.org/~john/suntour-xc.jpg

So I ended up taking my wheel up to "the Hub" in Long Beach and gave them a small donation for use of their tools. I was able to get both cones off. I over-tightened the cone I had removed enough to get the opposite cone removed. From that side, I was able to hammer the axle through. On one side - the bearing was frozen to the hub body. On the other side it was frozen to the axle - so the axle was only going to come out in one direction. I was able to get the ring seal off of both bearings though and the wheel turns much better now.

I realize this is definitely not an optimal situation, but the wheels were free, and it was just an exercise to see if they can be saved rather than recycled. Anyway, I think even in this state this wheel is better than my current front wheel.