But don't remove the cam gear with out first securing a set of cam alignment tools - I guess there may be a shade tree mechanic method of doing it, but I seriously suggest against it.
I posted in your other thread, and will post the picture here when I get it, but you must remove the rear cam covers/thrust plates, and install the cam alignment tools. Then, remove the timing belt and cam gear center bolt. You will notice that the cam gear has a hex shaped bolster - don't worry about this for removing the bolt, but after changing the seal, you will need to install the cam gear and loosely install the bolt. Install the timing belt, and aligning the cam gear with the alignment dots on the head, tighten the cam gear bolt. Then, remove the cam tools and install the thust plates again. While you are there, change the o-ring in the cover plates - expect to have to chip the old o-rings out with a sharp tool.
I'll post up the mechanical line drawings I have (someone else made them) shortly.
However, I wonder if someone with the cam tool, AND with a parts engine (or just an engine in some stage of dis-assembly) could do an experiment for us. If you take an installed cam and cam gear, and install the tool - then mark the head and cam gear in (called Mark #1) some fashion to indicate the alignment of the cam gear to the head. Then, remove the tool and rotate the came to let it 'detent' out in a neutral position - then mark the head/cam gear relative to each other again (called Mark #2). Then remove the cam gear. Since the cam is in a neutral detent, it shouldn't go shifting if you don't go turning the cam, and since the cam gear is marked on the head, it should be happy as well.
Then, put the cam gear back on, lining up the "Mark #2", and tighten down the center bolt. Then, rotate the cam and install the cam alignment tool to see how close to the "Mark #1" lines up.
I think if you're accurate enough with the markings, you can make it work. This would only work if you are not removing the cam itself from the head. If you are removing the cam from the head, you'd have to make a third mark on the back of the head - remove the cam thrust cover, and mark the cam relative to the head. Then you can disassemble the head, service the valves, etc, and re-assemble the cam to the head, lining up "Mark #3". As long as your marks are made with a punch (marking only the head, not the tail of the cam, using the alignment dowel pin hole for the cam side mark), the marks you made should not disappear if/when serviced by a machine shop.
I will try this on a parts motor some time this summer if no one else here chimes in.
Did you ever get around to trying this? Sounds like it should work! I have a set of cam alignment tools that I used when I replaced the timing cover. Now I can't find the stupid things when I need to replace the cam oil seal. Argh, guess I've got to keep looking.
i actually did something similar when i did the timing belt on my 95 new yorker(sold 2 weeks ago) and replaced the passenger side cam seal. i checked it out a few times making sure it settled at the same spot each time before removing the gear. i turned it to MY left until against spring tension, and let it come back lightly to stop from sping push. marked it. then did it a few more times making sure it came back to the same mark.
then removed the gear, it takes a little playing to get it lined up close upon re- installation, but after a couple of snugs and checking in the same manner as used for marking, i then tightened it completely up when satisfied the marks were lining up correct enough.
ran just as good as before so must have been close.