So, what kind of fitting is used to adapt air hose to spark plug threads?

Most auto parts stores sell the adapter fitting. I bought mine at pep boys.

I plan on doing this job on my 92 300 TE with 134K miles. On a trip this past weekend I used about 2 1/2 quart of oil in 1300 miles.

Questions:
1- Is the KD 2078 which is available at Sear what people are using? It's a universal spring compressor.

2- Is a magnetic keeper tool, available from Mercedes quite inexpensively, helpful in removing the valve keepers?

3- If the piston is positioned at TDC of the cylinder you are working on then there is no possibility of the vavle falling in the cylinder. Is that correct?

4- There is or was a special pliers to remove the old valve seal. Is this tool necessary?

5- Do people use a small pencil size magnet to pull the valve up? Or for any other purpose?

Hi, sorry I won't be of much help. I had this job done by a professional mechanic. I do remember that there was some confusion about the correct seals. The first ones he ordered were not the correct ones so he had to re-order. Our wagon is a 4Matic so I don't know if there was a slight difference in the engine seals. So be sure to use the engine number when ordering. the other thing I remember was that he used air pressure in the cylinder to hold the valve up. Sorry I can't be of more help. Good luck with the job. I do have a very good local independent shop that does all my work and I don't feel qualified to tackle this type. I have replaced the blower motor and also the tail gate struts, but that's about the extent of my capabilities.

Questions:

1- Is the KD 2078 which is available at Sear what people are using? It's a universal spring compressor.

You will need the type of spring compressor designed for removing the valve with the head on. It has 2 hooks that grab the spring coils. I believe the KD 2078 is one of them. Some types of compressors will only work with the head off the engine.

2- Is a magnetic keeper tool, available from Mercedes quite inexpensively, helpful in removing the valve keepers?

This is a must. Get the smallest one you can find because space is very limited. Also be sure to cover all the oil drain holes in the head because dropping a keeper down inside the engine could be fatal. A dab of grease on the keeper helps it stay in position when replacing it.

3- If the piston is positioned at TDC of the cylinder you are working on then there is no possibility of the vavle falling in the cylinder. Is that correct?

That is correct. With the piston at TDC the valve will only drop about one-half inch before it hits the top of the piston. There is still enough stem to pull the valve up.

4- There is or was a special pliers to remove the old valve seal. Is this tool necessary?

You should be able to pop the old seals off with your fingers.

5- Do people use a small pencil size magnet to pull the valve up? Or for any other purpose?

It's not really needed except for handling the keepers.

Thanks John, your responses are most helpful.

I have ordered the parts including the magnetic keeper tool from the MB dealer I often buy parts from at very competitive prices. I think the price of the special tool was less than $15. I did want to get the seal kit from a dealer using the vehicles vin# to be sure of getting the right parts and hopefully the highest quality parts.