Heads need rebuilt! Any tips?

[LaGrasta]

MY 246k '98 still runs fantastic and serves multiple purposes for our family. I've been chasing a poor idle for awhile and finally gave up and took it to a mechanic I trust. He ran diagnostics, then a compression test. #4 cylinder is low, valves are bad.
I checked machine cost in the SoCal area, $300/pair. Gasket set is about $100. I guess I'll tackle this; unbolt, have machined, bolt back on. Anything more I should know?

[MountainManJoe]

#4 cylinder is low, valves are bad.

if one cylinder is going out, then ....
how many miles on it?

$300/pair

per pair of what ... valves? You're not going to do just one cylinder are you?

Gasket set is about $100.

you're talking about a top end rebuild + kit + machining. To the restore just the top end you could be looking at thousands of $ .... On an old engine block that may be on its way out ...
I would have a serious think about it.

[LaGrasta]

For $300, the machine shop will rebuild both heads. The heads/engine/van have 246k.

[MountainManJoe]

well that's a reasonable price.
But I'm suspicious about why the valves would be bad. And how's the rest of the engine ... piston rings, crank bearings etc. ... and the transmission...

[LaGrasta]

everything else is 100%, runs fantastic and is super dependable.

[LaGrasta]

I may run some valve cleaner through it on a long drive, maybe that will be enough.

[LaGrasta]

We sold it to a Texas couple that doesn't have to smog it, $5800. They drove straight from our SoCal home to Las Vegas, then up to Colorado! We're gonna miss that one! We owned it since new, October of 1997.

[MountainManJoe]

Well you had a good run. Are you replacing it?

[LaGrasta]

No plans for replacement. Although I already have a few needs for a van, lol.

[Bret Schmerker]

Sorry to revive an old Thread, but King's Auto Repair (Oakley, CA, USA) identified the cause for (a) PCM-perceived miss at idle and (b) high NOx indicating lean-out at 15 and 25 MPH per CARB dyno test: Leaky valve(s), #5 cylinder. King's no longer has the resources to fix the leak(s). The Vortec 4300 CSFI requires dismounting to accomplish the valve job anyways, so a double full head rebuild comes into the question.

So I gotta ask: With the pre-existing cab door latch problems and the compromised helper-door window motor, plus the HVAC control breakage and windshield-washer nozzle failures, is the cumulative repair price more than the potential value upon restoration?