Thread: ford Ranger diesel Woes

Shrt story, #3 son, the newly minted Motor Mechanic bought a 2nd hand Ranger - Private sale - 3 litre (?) / 4cyl common-rail diesel. Went well, Useful amount of torque etc.

Sadly the viscous fan failed (unlocked) , going uphill...and ..... Blew it's overflow bottle and lots of black-tainted Green Stuff everywhere. Waited to cool, then drove downhill & home. Quietly.!
Checked everything including the stupid oil-cooler-in-block's-water-jacket. Cracked head around #3 & #4. Deemed 'UN-fixable' so his Mate-Of-A-Mate sourced a brand-new Chinese head, complete with valves fitted. At Mates-Rates obviously, being in the 'trade'...

Installed and run for a week... but....
Oil light flickering, running tooo warm and now it's WATER in the oil. - Catch-can says so...
Head removed, sent off to another 'Head' shop and it is a banana... Several $$$$$s later, and new gasket/bolts/swearing and it's back on.
Trial run and.... oil light flickering and running warm(er)

Son has increased his vocabulary, and is totally 'over' the car. But between himself and late-night mates, has improved their Cyl-head R/R times !!!

Question: - It is the opinion of this (ex) Range Rover owner / Father of Master Mechanic, that the unstable oil pressure lamp, coupled with running warm... indicates a cracked or otherwise damaged BLOCK.
- What are my chances of being correct ?

- Lower half of engine was left in the vehicle and by virtue of being cast iron, was assumed to be ok. No Visible-to-the-naked-eye cracks etc noted. 'Crack Dye Test' not done.

Edit:- To the best of my knowledge, no straight-edge was run over the block... I know, 'cos it is still in my shed in exactly the same spot where I left it.

My original suggestion of buying a 'good' 2nd-hand engine.... went nowhere.

Block could be warped, really need to pull it out and strip it to find out for sure.