I just finished replacing the valve stem seals on my '88 260e and it went flawlessly thanks to the help from this board.

I used the compressed air method described by Dennis about a month ago using 100 psi air and holding the crankshaft from turning with a wrench on the crankshaft bolt. Looking thru the spark plug hole with a flashlight, I turned the engine to a little past TDC- until I could see the piston just starting to go down, and then put a big 27mm socket on the crank bolt and braced it against the garage floor. I figured with the piston up high, I wouldn't lose the valve if my air compressor quit or something. When I let the air into the cylinder the engine tried to turn and I could see the wrench tighten up.

After removing the spring from each valve, I shut off the air and checked the play in the valve guides. There was a little play in each one but not too bad yet. The valves moved down only about 1/4" before hitting the pistons. No chance of losing the valves with this repair method but this is definitely an interference engine.

The only problem I had was with the No.6 cylinder. I could not see into the cylinder and had to use a long thin screwdriver as a "feeler" to check for TDC. I also had to loosen the trans. dipstick because it was in the way of the valve compressor tool.
After compressing the springs, I had to rap the valve spring tool with a hammer to free the keepers.

Had to be very careful handling the small keepers and rocker shims because I think they could fall down into the oil drain holes in the head. I used foam ear plugs to temporarily plug the drain holes but it's very important not to forget about the plugs and leave them there.

I also sealed the upper timing cover and replaced the serpentine belt.

Thanks everyone for the excellent help and advice, and Fastlane for getting all the parts to me so quickly.

John Plut