Need advice on second hand 2.9L.

[Terbo]

Hello people!
I need some advice, i have a 1990 2.9 Ranger with toast for cylinder heads. Found a fella selling a 2.9 out of a parts bronco, the odometer says 28k but is probably 128k or 228k due to rollover. What things should i look for when picking up a used motor? Any idea what i should pay for it? he said it should run. I'll prolly need to take it out myself.

 

[Shran]

If you can hear it run that would be best

Engine oil being way overfull would point to coolant or water in the oil. Just walk away at that point

If you can't hear it run and he doesn't have a video of it running, then I would pay scrap weight for it because it very well might be junk. $50-100 at most

If it's been sitting for a long time make sure it turns over by hand and makes several complete revolutions. I got a 2.3 a while back that sat for about 10 years and it was stuck. Had another 4.0 that sat for 17 years that fired right up and ran great though. You never know!

 

[Rick W]

My 87 has a 2.9, it was blown when I got it and I put in a rebuilt one I acquired from a friend who wrecked his truck after rebuilding his engine.

Talk to a local machine shop who rebuilds engines. Find out what they’ll charge to pull the heads and check it out before you put it in, that’s usually pretty cheap, and that’s the best time to fix something or improve something.

I had heard that the original factory 2.9’s had weak heads that were prone to cracking if the truck was overheated. The guy who rebuilt mine put on the improved heads.

I’m far from my knowledge base on this, but just use some common sense and research “problems with 2.9 engine engines.” Virtually every engine has a couple of dark spots, do some research and learn how to spot them, or figure out whether they’re expensive to fix.

 

[97RangerXLT]

i gotta agree with Shran on this one. see if you can get a video of it running. Also ask why it is being pulled out of the bronco. is he just parting it out (rusted out or blown transmission, wrecked etc) if this is yanked as a part out of a running vehicle that is otherwise good... i would have questions. does not mean the engine is bad, but why part out a running and operating vehicle, other than you can probably get more money for the parts than the whole.

AJ

 

[rusty ol ranger]

Make sure it spins by hand if you cant hear it run.

Pull the dipstick...check it for shavings or coolant.

 

[IRKillroy]

Hello people!
I need some advice, i have a 1990 2.9 Ranger with toast for cylinder heads. Found a fella selling a 2.9 out of a parts bronco, the odometer says 28k but is probably 128k or 228k due to rollover. What things should i look for when picking up a used motor? Any idea what i should pay for it? he said it should run. I'll prolly need to take it out myself.

I'm going to assume you already got them, but if you were going to get them, get the older model (89 - 92; "89TM" imprint and square rocker-arm pedestal) because they have improved castings.

So, I'm not gonna lie, I used the Grok to put this together for you so you have a nice list on what to look for on these heads. Sadly World Products no longer makes their replacement heads. I wish you luck but recommend that you maybe consider an engine swap!

Crack Inspection (Primary Concern)​

• Visual locations to examine closely:
  • Top surface across the valve cover gasket area, particularly right-front and left-rear corners.
  • End cylinders (1 and 6): base of valve springs, between combustion chambers, and around spark-plug holes.
  • Combustion chambers: between valve seats, around exhaust ports, valve guides, and spark-plug-to-valve areas.
  • Deck surface and bolt bosses (especially early pre-1989 heads).
• Look for hairline cracks, dark lines, or discoloration paths indicating coolant or oil migration. Cracks may appear as fine fractures or repaired welds. Many are not visible to the naked eye; subsurface cracks are common.
• Note: Machinists report that minor cracks are rarely repairable successfully; replacement is preferred over welding.

Deck and Surface Flatness​

• Place a precision straightedge across the deck (head-to-block mating surface) and manifold surfaces. Use feeler gauges to measure any warpage. Excessive deviation (typically beyond 0.003–0.005 in., per standard tolerances) indicates prior overheating or distortion and requires resurfacing or rejection.

Combustion Chamber and Valve Train Condition​

• Inspect combustion chambers for pitting, erosion, white deposits (sign of overheating or coolant intrusion), or burnt areas.
• Check exhaust valve seats for disintegration, pitting, recession, or looseness (a known 2.9L failure mode leading to compression loss). Intake seats are less prone but still verify.
• If valves and springs are installed: Examine valve faces for burning or pitting; check stems for scoring or bending. Wiggle valves in guides to assess excessive play (indicating wear).
• Verify all coolant passages are clear and free of heavy corrosion or blockages.

Thread and Hardware Inspection​

• Inspect spark-plug threads and head-bolt holes for stripping, cross-threading, or damage. All must be clean and serviceable; head bolts are torque-to-yield and should be replaced regardless.
• Check for any previous repairs (e.g., helicoils or welds).