I decided to adjust the valves on my '79 300SD (200K miles) today since it has been 25K miles since it was done last. I removed the valve cover and took a quick check of the first valve that had the cam lobe 180 degrees to it. I use go-nogo gages to check the clearances: .003 and .005 inch for intakes and .013 and .015 inch for the exhausts.

The valve clearance of that first was in spec. So I started to check the clearance of the other valves and they were all within spec too.

Has anyone else had this happen after 25K miles? Maybe the valves don't have to be adjusted as often as recommended?

I also checked the chain timing and it was right on. I've only had this car for the last 40K miles and I have no maintenance history.

I use Castrol Syntec 5W-50 and change it every 10K miles along with the filter.

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