I'm probably qualified to answer this, at least from one perspective:
- amateur mechanic (very); but grew up in Detroit w/7 brothers and someone was always working on a car;
- bought 179k 2002 XLS (4.0l SOHC) two years ago with busted engine due to timing chain, good body, for $500 + towing
- picked up used cherry picker and engine stand for $200 in S.E. Mich. (craigslist is your friend; but need access to a p.u. truck);
- bought the $150 (?) OTC Timing tool;
- the truck had sat in a woods for 3+ years w/lots of mice damage. I wound up also replacing fuel pump; all four calipers + discs + pads; starter; alternator; radiator; a/c lines; a/c compressor; power steering high pressure hose (b/c I damaged the original standing in the engine bay); blower motor; air box door; driver's door handle; driver's door latch; plugs; wires; fuel injectors; water pump; thermostat housing; thermostat; all hoses; all belts; idler pulley & tensioner; one exhaust manifold; two forward catalytic converters (non-oem); exhaust from Y-pipe back; eventually tires; one headlight; windshield; replaced airbag trigger; repaired seat belt wiring that caused airbag light; eventually replaced both front struts; front inner and outer tie rods; eventually both front wheel bearings; all filters and fluids; and some parts I'm forgetting;
- had to repair/replace lots of wiring, too (including that tricky center antilock brake sensor that fits on the rear diff);
- swapped 1 &3/4 trailer hitch with a 2-inch Class III hitch from another '02 Explorer
It took me the better part of a summer to get everything set up and worked out, nights and weekends. I pulled the engine (not easy, especially first time), pulled the heads and sent them to machine shop (bent Bank 1 valves); ordered the complete Cloyes timing chain kit; installed it; noted some what I thought was minor block damage from the right rear timing chain failure and attempted to repair; spent lots of time picking out bits of broken chain guide out from the lower end.
I pulled the pistons on this job, and was very impressed how new the cylinder walls looked (cross hatching and all). Very impressed. I think these lower ends are generally solid and built to go $300k.
Put it all back together, managed to get it back into the truck w/o breaking the new radiator (removing/installing these radiators is a huge pain). Drove like **** for 20 miles. Took it too a mechanic to sort out some fuel pump wiring issue I missed. Picked it up a month later, drove 10 miles, and blew a hole in the block. Either the damage from the failed timing chain or I screwed something up installing the new crank bearings, etc.
AAA towed it back to my place where it sat for 1.4 years, until last summer.
Found on Craigslist a 2002 XLT built the same month/year as mine with some body and other damage. But the engine seem to run fine (116k miles). Paid $200 for it + $100 tow.
Pulled the engines from both trucks; pulled the new timing components off old engine and installed on "donor" engine. Decided not to touch the heads (since no timing failure) or lower end. I pulled the lower-mileage torque converter and the solenoid pack off the donor truck and installed them on the donee vehicle for good measure.
Put it all back together. Ran kinda ****ty. Lot's of misfires at idle. Drove from Michigan to Texas to Georgia to Michigan that way (w/old struts and tires). Made it.
Lots of hangwringing and help on this forum later, I decided to re-time bank 1 (did not need to pull the engine for this; relatively easy with the OTC tool). My timing on that bank was off, it turns out.
I've put close to $5k into it since two summers ago. With the new stuts, inner and outer tie rods; upper ball joints, new tires, fresh alignment, and a new rear u-joint (this is a 2wd vehicle), the truck rides like new.
I LOVE IT! I'm letting my kid drive the Volvo S60, I like driving this truck so much.
Oh, late last summer, I started losing overdrive on highway on my way back from a 200-mile family trip. No big deal; I slowed down to 60-65 mph and made it home fine. Ordered the servo bore kit ($200) from the guys in Wisconsin, and with a buddy's help (he had access to a lift), installed it (overdrive servo only) a couple of weeks later. The transmission runs perfectly since; I'd have no hesitation driving this truck cross-country.
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Sorry for the long story, but if someone had told me what I was in for when I started, I'd for sure walked away. I'm glad I didn't. Tons of time and several thousand dollars in parts and service. But I actually got a lot of satisfaction doing this work, most of it possible due to the excellent guidance of contributors to this forum (including Imp). And now RockAuto loves me!
From your comments, it sounds like you might be better off selling the truck for a couple hundred dollars to someone who wants to rebuild it. If you decide to hang onto it, you'll definitely need to arrange other transportation for a few months, sounds like. Good luck.
