1972 450SL
4.5 engine: 117.982
220,000 miles

I took off the valve covers today and to my horror here is what the right bank camshaft, lobe #3 exhaust looks like (right most lobe in photo). The scoring is only 3mm wide and 16mm long. My finger nail grabs a bit as I slide across it so it's not a really deep but appears to have gone through the hardened (polished) surface. I Really hate to buy a new camshaft and rockers because of the expense. What do you think? All the other lobes have no scoring except a slight scratch on intake lobe # 4. You can maybe see that on the left most lobe in the photo and the scratch is on the right side of the lobe. What will happen if I don't replace the cam?

BTW, my cams are numbered 52 left and 53 right. That's kind of weird since the FSM shows that number going into other 3.5 and 4.5 engines but not for the 1972 450SL!

Thanks,
Elliot

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1972 450SL
1982 300D Turbo