1988 300CE, 150k.

Used to use a quart every 2k miles, then, ca. 120k, did valve seals and oil consumption disappeared.

Camshaft and rockers replaced @ ca. 135k, but no other engine work at all.

Mark

__________________
I never go far without a little Big Star

1994 E500 199/Gray 82k
84 300D (Salty) Orient Red/Palomino 141k
88 300CE (Ersatzhammer) 904/Java 163k -- Turbo Technics twin turbo kit, AMG Gen I body kit, Sportline steering box and steering wheel, Sportline/Eibach /Bilstein Sport/500E suspension, Quaife LSD in 210 mm diff case, Silver Arrow brakes.
88 300CE Brabus 3.6 199 on Black 44k

That describes my car exactly ('87 300E) but I have not replaced the upper timing chain cover gasket. That's where it leaks, though.

Sorta the same story.

About 5 years ago, I started burning about a qt every 1200-1500 miles. Had the valve stem seals replaced then.(at 75,000) Now, I don't need to add any between changes. 3000-3500 miles. No other top end work

Before I bought it in 2001 (with 41k then) I had a PPI done and the MB dealer (Lokey in Tampa) said it needed a head gasket as there was an oil leak at the left rear. The seller and I split the cost.

She doesn't leak or burn at all today.

I've read here, and I believe it, that the bottom end of the 103 is darn near bulletproof. The valve and guides will wear because of cam design & lash. The timing chain design lends itself to longer life that a 104.

I still have the original water pump. New radiator this year. New exhaust last year. Original cats still aboard. Fuel system still original, except the fuel pump relay went last month.

1988 300CE
M103.098
110,450 today
Manufactured Stuttgart May 1988
Sold MB Manhattan NYC July 1988.
I am the third owner afaik.

Edit: Who recycled this thread? I just notice I posted on this thread a long time ago. Well, at least I my stories jive.

Well, since my 157K mile ' 88 300SEL is not burning any oil between the 3-4K mile intervals, what are the chances that a PO already had work done to the engine?

I'd say, speaking as a layman that after 20 years and 157k miles the odds are good a PO did some of those things. You have no signs of external leaks around the head gasket or the valve covers?
I don't think the valve seals would have lasted that long without showing a consumption problem. That was probably done, as it is a "head-on" fix and seals were prone to dry out and "leak".