Called the cam grinder and he says there an "05" on the end of the cam.

35mm would make sense, he measured it at a little over 1.375 in its current state.

__________________
1972 280SE "Babe"
1968 250S 4spd

Hello,

OK, for your "05" camshaft, here are the specs as listed in the Mercedes Technical Data Manual for a 280SE/8 are; 34.975 mm to 34.959 mm for the shaft. The bearing diameter (cam holder opening) should be 35.00 mm to 35.016 mm.


Try this trick for installing and removing rocker arms. Use an allen which fits the hole nice and snug.

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)

JA

You are getting a litlle Sloppy with your tutorial pictures...

You usually have the pics. on a white background with Labels ...and what size allen ????

...

You certainly do go out of your way and are the Best.................

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A Dalton

Thanks to all for their help on this one, the cam grinder has the info and I should have a cam on Monday.

So, let me make sure I have this right.

Head has valve/spring assemblies installed and nothing else.

What's procedure from here? The last time around, I threaded the cam through the towers, lowered that assembly on to the head, and hand-tightened the hold-down nuts (just a few lb-ft). At this point the cam was bound. (No rockers)

So if I'm reading wbain5280's post correctly, this is not cause for concern, and should bolt the head to the block before I worry about whether the cam is bound?

I'll get the machinist to measure the top of the head once I get the cam back. I don't think it was flat, but I couldn't swear to that now. If it's not flat, should we just shim anyway?

Joe, I'm not totally sure I get your vise-grip/allen wrench trick. You're suggesting that instead of a valve spring compressor, or just as a handle to keep your fingers out of the way when the compressor lets go?

Thanks again everyone!

-Zandr

__________________
1972 280SE "Babe"
1968 250S 4spd

Hello,

Thanks Walter, you know my style! I aways appreciate your thoughtful insight and advice also. By the way a 5mm or a 3/16" allen wrench will work fine.


Zandr,use the tool to remove rockers by inserting the allen and then lifting the vice grip. The cam forces the valve to compress, swing the vice grip to one side and its off! To install, place the end of the rocker on the pressure pad and lift the vice grip. Swing the rocker into position and lower on the ball stud! If you encounter any resistance as the valve is compressing, you may have to rotate the engine slightly since the valve may be contacting a piston.

Yes, I like to install the cam and holders on the head, oil it an its holders up well. Torque to specs in three passes. Turn the cam during each pass. When finished, you should be able to turn the cam by hand. Some resistance is ok.
If so go ahead and connect the timing chain. Turn the engine by hand in the normal direction of rotation to double check the timing marks. Install the rockers next if everything is ok. If you have to remove the cam stands to shim ,only unloosen the head bolts that are needed. or you may damage the head gasket. Torque all the head bolts to specs. Re-torque head after first warm up and again at 500 miles. Make sure you do not have an air lock in the engine during start up or you will overheat. The top tank of the radiator will get hot when the coolant finally begins to flow. Do not test drive until the radiator top tank is hot.

__________________
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)

OK, got the head back from the machinist with a set of brass shims he made for the cam towers. He made the shims based on static measurements with the towers mounted to the head.

A friend who is an A&P (aircraft mechanic) didn't think I'd need the shims, and suggested torquing things down using a sheet of butcher paper as a gasket, just as a trial fit. Sure enough, with everything torqued to spec, the cam turns fine. So, new timing chain and tensioner, spin the motor around a couple of times to verify timing, and all's well.

Which means the whole exercise has been a false alarm. Ah well, live and learn.

Thanks again everyone for your help... and I'm sure I'll be back as soon as I get to the next problem.

Tomorrow the rockers go on, adjust the valves, and then start re-connecting all the plumbing and fiddly bits.

-Zandr

[EDIT: Yes, I did reassemble everything with a real head gasket. ]

__________________
1972 280SE "Babe"
1968 250S 4spd