I tried searching this forum but couldn't find the answer, so sorry if I'm repeating a frequently asked question.

I'm want to replace the valve stem seals on my '71 250C (M130) and I'm trying to figure out if I can do it with the cam still on. BTW, I want to do it with the head still on. If so, how do I take the rocker arms off?

I have a Haynes manual, but it doesn't seem real helpful, because it talks about doing it in the context of a complete head rebuild.

Any other advice is also appreciated.

Thanks,
Scott

You will have to pressurize the cylinder with an air compressor, a spark plug adapter and a breaker bar and socket on the crank bolt to make sure the engine doesn't turn, with a helper of course.

You remove the finger followers by using the special tool used to adjust the valves, or a crowsfoot wrench, and screw the adjustment half all the way in to the base.

You will also need the special tool to depress the valve spring retainer. There are two springs you have to remove, inner and outer.

My M103 uses one spring so it's easier.

__________________
Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.

Thanks for the advice, Warren. I wasn't 100% certain from your answer, do I take the cam off? It looks to me like I have to, because there's no way my valve spring compressor will fit with the cam still on.

You will need this special tool to depress the valve springs.

http://www.peachparts.com/diy/mb_tools/mb_tools.php?page=13

4th one down 123-0361


You cannot use the generic SK tool to compress the springs from the outside because there is an inner spring and you will not be able to get the keepers out.

Get a magnetic pickup tool to remove the keepers, it's a telescoping tube, like a radio antenna, with a magnet on the end.

__________________
Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.

I've never had a problem using the SK type spring compressor, and I've always used just a big screw driver to remove the rocker arm. I leave the cam in place.

Chas-

Do you have any more details on how you remove the rocker arm with a screwdriver? Also, with my cam in place, it seems like on some of the valves there will not be enough clearance with the cam support tower.

Have you done this on the M130 engine? I appreciate everyone's help.

Thanks,
Scott

I put the tip of the screwdriver under an adjacent rocker and push down on the spring retainer with the blade of the screw driver. The valve needs to be opened only a small amount to allow the socket end of the rocker to be lifted off the ball stud. When doing exhaust valves ensure the piston is not a TDC. This gives some room for the exhaust valve to open.
It's been a while since I have done stem seals on the single cam engines, but I think this works for the M130- sure won't cost you much to try.

Here's an update on my (slow) progress. After getting the rocker arms off, I decided there was still no way I was going to be able to do it with the cam on (at least without the special MB tool). I ended up having a welder make me a lever-type valve spring compressor out of 1 1/4" square tube.

Borrowed my brother's air compressor and started at 9:30 last night. I now have . . . drum roll . . . one changed and 11 to go. Took me about 15 min. to get the seal changed and 30 to get the keepers for the retainer spring back on. Hopefully that will get quicker.

-Scott

Hello,

I have a lot of expensive and complex special tools for removing these rocker arms. However the simple arrangement (shown in picture) works just fine and you probably already have the pieces to do it!

Attached Thumbnails

 

__________________
Joe Alexander
Blacklick, Ohio
1964 220SE Rally (La Carrera Panamericana someday)
1966 Unimog 404s (Swedish Army)
1969 300SEL 6.3 (sold)
1969 280SL Pagoda
1973 280SEL 4.5
1974 450SLC FIA Rally car (standard trans)
1982 300D turbo (winter driver)
1986 560SEC
1989 Unimog FLU419 (US Army)
1991 300TE (wife)
2002 SLK 32 AMG (350 hp)

Thanks, Joe. I'll remember that. My rockers are already off (or I'm off my rocker ).

Worked on it for a couple hours last night and I now have two whole cylinders (4 valves) done! I'm starting to get it down. I've actually gone back to using the $20 generic compressor from the auto parts store. It is difficult, with the inner valve spring, because I have to tighten it to compress the outer valve, then press down hard with my arm to compress the inner spring. It allows me to work the retainer around a little bit better than the lever-type compressor I had made, which makes it easier to get the keepers out.

The bad news is that after finishing my 2nd cylinder, I realized that I didn't get one of the seals on the other cylinder pressed down far enough, so I'm going to have to do that one again.