Bicycle Mechanics - Stuck stem

I picked up a used Trek 710 and wanted to raise the bars slightly but the stem will not budge. I tried penetrating oil a couple times, then looked at the head tube from below and it looks like there is a shim around the tightening wedge. There is no rust for penetrating oil to work on. It is stuck tight. Anybody know how to solve this?

Thanks

Read this:
http://sheldonbrown.com/handsup.html

Take note of the paragraph at the bottom of the article. Could this be the case in your situation? Make sure the center bolt is loose and that you have tapped on it to see if it can be knocked loose. Then you may have to try tapping up on the bottom of the stem inside the steerer tube (underneath) with a suitable drift punch. Good luck.

Sorry to ask the obvious, but you have tapped the quill bolt firmly with a rubber mallet until it drops back into the recess? The "shim" could be just the edge of the stem surrounding the expander wedge.
I don't think it would have a shim in it, unless for some reason they used an old Schwinn stem? They were small enough to put in a thin shim on a 22.2 steerer, but not likely.,,,,BD

Thanks for the quick response. It looks like I have a split quill with an expander bolt, and it looks like it is pulled into the quill by about 1/8". Tapping with a rubber mallet didn't do anything. Looks like I 'll need a little more force. I'm afraid too much though and I'll damage the threads on the bolt and expander. I think I have room to pull the stem up some. The previous owner was short, in fact the frame was a little big for him.

Unscrew that bolt a ways and go nuts with the mallet. The bolt is your best and easiest option, by far. You are not going to strip threads, and if you do, stems are cheap. Also, whether the bolt does or does not solve your problem, the steps you will have to take if the bolt doesn't work are mostly destructive anyway.

unscrew that bolt a ways and go nuts with the mallet. The bolt is your best and easiest option, by far. You are not going to strip threads, and if you do, stems are cheap. Also, whether the bolt does or does not solve your problem, the steps you will have to take if the bolt doesn't work are mostly destructive anyway.

+1.

If you have access to a brass hammer try that. I've whaled on a few stems with my rubber mallet before and got nowhere. Even a regular ballpeen hammer, the worst you're gonna do is mash over the head of the bolt and they are replaceable.

Well, the stem and expander are both steel. Give it a few more good whacks. I have done many of them, and have never damaged the threads on one yet.,,,,BD

Thanks. Heading out of town for a few days - I'll use the bigger hit approach later this week

Might as well give it another application of penetrant before you go and let it soak in while you're gone.

I removed the brake, set the bottom of the head tube on a wooden frame, put a socket allen wrench into the stem bolt, and with about 3 or 4 hard hits it was loose.

Thanks for the good advice.

......put a socket allen wrench into the stem bolt......

Thats a good tip. I'll have to remember that one.
Glad you got it out.

That's about the most you can hope for with some old school quill stems. Congratulations!!:D Be absolutely certain to put a light coating of grease on everything from the top of the quill bolt on down. That goes for where the wedge meets the quill. Disassemble the whole thing, clean the threads with a wire brush, etc. It will make it so much easier the next time it needs to come out, and doesn't cause slipping no matter how weird it seems.,,,,BD