Advice vs pros and cons of engine flush

I’ve been silent for a while - just back home after a couple of weeks out of town. I appreciate all of the responses and suggestions. I will try a number of the suggestions. FYI - I just pulled the dipstick and the oil is pretty clean. It’s probably been over a year since the last oil change but, unfortunately, that might mean less than 1000 miles on the “fresh” oil. I have the car running and functioning good right now and hopefully I’ll increase frequency and distance of driving.

Pulling the valve cover and inspecting cleanliness, etc sounds like a good next step. Any actual adjustments or push rod replacements will depend on what I find.

I was asked what oil I used. For the first 130,000 - I faithfully used QS 30 high detergent oil (I’ve read negative stuff about QS since) and it actually kept things nice and clean in the rocker arm area. Since the rebuild over 30 years ago, my annual mileage has become very low and I’ve used different multi-grade oils & timing of oil changes have been based on a dirty oil stick and the passage of time - not mileage. If the rocker arm area is clean - I’m going to suspect that a dirty oil pan (caused by years of very little driving) may be why the oil is getting dirty sooner than it used to.

I was interested in the various engine flush techniques. When my car was new, an Air Force motor pool guy told me to add a quart of automatic transmission before each oil change and I did that for many years. I think that worked pretty well based on an internal inspection around 100K miles. (Almost 40 years ago and I have no recollection why I pulled the heads.)

Thanks again for your inputs.

Another project ahead is due to minor but annoying oil drips. The gaskets are now 34 years old. With about 60K on the engine - I feel that, if the engine needs to be pulled to replace gaskets - why wouldn’t I go for an engine rebuild at the same time? Up ‘till now - I’ve kept everything but the paint and exhaust system original. I’d be interested in your thoughts of a rebuild vs a reputable crate engine.