Engine was spotless from bottom while oil pan off.

[strombony]

But...is this a good way to verify if the entire engine is in the same condition?

I recently had my oil pan gasket replaced...Mechanic said the engine was spotless/very clean, "in his words"... However, is that really an accurate way to know the rest of the internals are sludge free? I've only been using Pennzoil, Valvoline on occasion, and a couple runs of M1 a year ago. It's a Dodge V6 3.3L

 

[JAG]

The top of the engine is probably the first/easiest to get filthy. It is still good that the bottom end is clean of course. If it looks clean inside the oil fill cap area, then your entire engine is probably clean.

 

[ikeepmychevytoo]

I had to remove the oil pan after rubbed on a construction area and leaked. So here's my snapshot. Bottom of the pan was black and was the dirtiest part in this 24 year engine. It costed solvent bath to clean. Internals were just lightly covered with fluidy brown varnish. Rubbing with finger the varnish would come off and the shiny metal would show. A year ago when the valve cover removed, the top was covered with darker varnish but vouldn't come off by simply rubbing.

 

[BrianWC]

If I weren't at work, spending your tax dollars (thanks guys!) I'd attach a pic from my photobucket account that shows what the bottom end of my engine looked like. The valve train was varnished with scattered hard a soft sludge. But when I later pulled the pan, the bottom end was completely coated in the nasties. So, it may vary from engine to engine whether the top or bottom is worse. But if he says "spotless" I'd wager to say just keep doing what you're doing for maintenance and don't stress out.