you have to get an air hose and an adapter to screw into the spark plug hole so when you take the spring off your valve doesn't fall down into the cylinder. At least that's how you're supposed to do it, you may be able to just move the piston up to TDC and hope the valve will be kept up high enough so you can get a grip on the stem.
Not to hijack the thread or anything but are the stems seals from toyota the best ones to use? I've used ones from my topline rebuild kit and ones made by Beck/Arnley and they both failed within a month
Its not that tough a diy job for anyone with a Haynes manual and patience. Its really just taking stuff apart and putting it back together. One thing to be extra careful with is putting the spring keepers back in, they are tiny and hard to manipulate with oily fingers and they tend to just disappear when you drop one. Only other thing that might require some finesse is lining up the cams, T-belt and distributor but since the 5m is non-interference motor, you won't break anything if you misalign, just move one tooth and try again. Special tools required are, valve spring compressor (~$25), a simple magnet fetch tool to remove spring keepers, 1/2" hose puller pliers (~$15) not required but make yanking the seals a piece-o-cake, torque wrench (~$25) and a 6' soft nylon rope 3/8" dia (feed rope through spark plug hole and turn crank till rope pressed against valves so they don't fall in). Make a weekend project and replace all the hidden heater hoses and all top end gaskets and seals while cam boxes and plenum are out of the way and mabe clean out the EGR too. Valve stem seal job is great opportunity to do a bunch of maintenance the car probably needs anyway.
Never had any problems with any aftermarket stem seals and I've done this quite a few times. Possibly slightly bent stem causing premature failure. Was failed seal ovaled upon removal?
It probably took me 6 hours total do the exhaust side alone, tearing down and putting back together.
When I had the springs removed the valves moved up and down easily in the guide but there was no play to any side. The guides, valves, and seals were all replaced 12k miles ago by a local engine builder from my Topline rebuild kit. The seals were very tight on the guides but seemed slightly loose all the way around the valve stem. The Beck/Arnley ones I put on were a little tighter but they still are leaking oil at the rate of over a quart every 1500 miles. I use Mobil1 synthetic only, 15W50 in the summer and 5W30 in the winter. There cant be anywhere else I am losing oil cause my engine is clean and my compression was over 180psi on all cylinders last time I checked. I also get a lot of blow-by which i'm sure is from the bad stem seals.
Nice call on the Mobil1 Synthetic. I was convienced when I used it in my high milage 1990 ZX 600 Ninja motorcycle. That thing ran hot as hell and redlined at 14,000 RPM and I took it there at least twice a day! It was tuned to the nuts and it ate many larger motorcycles for breakfast. Anyways it beat the $hit out of every regular oil I tried but Mobil was great stuff. Any oil that can servive 8,000 km's in that engine is good enough for me!
Anyways, I don't know where you are located but if your in Canada Canadien Tire has a lend-a-tool program that has a valve spring compressor so you don't have to buy one. Valve seals a easy to change, but you will deffinatly need to hold the valve all the way up with air or the rope trick. Have fun!