Replacing valve seals

[johnk]

My 280sl was blowing a little blue smoke when I test drove it a few weeks ago in Saint Loius. We drove it for about a half hour and there was very little visable smoke. It was delivered here in cold weather the Sunday before last and smoked more than it did in Saint Louis. Two days later in 60 degree weather it did not smoke as much at first and we hoped that driving the car might clear up the problem. That was great for about thirty minutes until it started smoking so bad the people behind us could not see. We just pulled the valve cover and it appears that two of the exhaust valve seals are popping up.

The car has only 73,000 miles and hasn't been driven much before I bought it. Is it possible or advisable to replace the valve seals that are loose without pulling the head? I know you can do it on some other makes of cars by keeping pressure in the cylinder with air through the spark plug hole. Or am I better off to just pull the head and see what needs to be done?

I appreciate all the advice I can get!

Thanks
John K

[stickandrudderman]

Certainly you can do it in the way you describe but if your valve guides are worn then the new seals won't last very long at all.

[johnk]

Thanks Stick. If we see that the valve guides are loose or worn we will go right to pulling the head so not to waist time.


John K

[230slhouston]

I had the same issue. Smoke under certain conditions. Wanted to test the theory of valve guides being loose.....i put in  set of valve seals. Can be done insitu without taking of the head. I do it myself so only the cost of the seals are factored. There where some seals that popped out of the guide. Took me half a day, car was perfect for a little while and started smoking again. 4 Seals popped out of the guide.

I am going to overhaul the head now that i have the engine out for my paint job. I could not tell if the guides where loose while installing the seals.

MBP

[johnk]

Thanks.
What did you use to compress the springs?

[230slhouston]

Std tool i borrowed. I will take a picture and post it. To keep the valve in place i bought one of those sockets that screws into the plug hole and used compressed air.