Noobs next task...Fixing that knocking noise

[TimQ]

Before this time last year, I never touched a car engine in my life. Learned quite a lot poking around on the boards and have gotten lots of great advice. I finally fixed the intermittant stalling problem that hassled me for quite a while. Turns out it was the darned ESC. Once I bypassed that, she runs like a champ.

So, as is the case with these old girls, you fix one thing and another problem comes to light. In my case, I seem to have a bit of a rattle or knock. It's loudest as I sort of cruis slow out of the neighborhood, but it would always be there. A mechanic told me it sounds a collapsing lifter.

As background, I have an 86 C10, V6, 4.3 automatic with 89,000 original miles. Yeah...never gonna light em up at the light, but it serves my purposes of hauling mulch and lumber.

Poking around the boards and elsewhere, I figured I'd try some Seafoam. Seems to have done quite a nice job. I put some in the oil, drove till the oil was dirty and changed it. Added some more, drive a bit more, and plan to change the ooil again today.

Now, when I start the truck up, the tick is still there but is diminished. And, if I drive 20 miles or so, it pretty much goes away.

Way back last year, I had the one valve cover off and I remember seeing some sludge. Since I had no clue what I was doing...I just figured it was normal and moved on. Recalling that, I decided to pull the valve cover again this morning. Here's what I found.








Truck runs generally fine. I get a good puff of smole on startup, especially after a few days. I also notice a bit of smoke at stop lights if I tap the throttle. But, cruising along there's no noticable smoke and the oil use has never been problematic.

I'd imagine this gunk might be causing my ticking. The seafoam seems to be breaking it down. So, my question now is...what to do? Do I keep changing the oil and adding Seaform every 100 miles till it goes away? Do I scoop out as much of this stuff as I can first? Do I just put the covers back on and forget about it?

Just trying to make this truck last as long as I can. And, with less than 90k miles on it, it would seem I have a ways to go if I make the right choices.

Thoughts?

Thanks.
TQ