Generally, dropped liners seem to be associated with engines which have been either over heated or at least gotten very hot. There have been others which dropped liners for no apparent reason.... low probability.
when you take the heads off, examine the lip around the cylinder carefully to ensure the liner is where it should be and there's no evidence of movement. If it seems to be OK, then don't fret any further about it!
If the engine is not burning much oil, the compression numbers are OK and the bores look OK then I'd just do what has to be done re. the heads and be done with it.
FWIW: At 250k, it maybe worthwhile having the injectors cleaned professionally if they haven't been done previously. I contacted a mobile EFI expert. A bloke arrived in a van all kitted out with a test bench/oscilloscopes /all sorts of spares etc etc .. $20 each injector incl. all new o-rings etc. He cleaned them ultrasonically then ran them through a series of tests for spray patterns etc and then a volumetric test whereby they each pump 100ml at the same time. When the test rig stopped there was less than 0.5 ml variation between all 8 injectors
He then sealed each of them in a plastic bag for later refit...
The big temptation is to keep going and replacing lots more stuff "while the engine is pulled down...may as well...etc!!" Assuming everything else is functioning OK then a competent job should see the heads OK for another 100k at least. I rationalised the extra expense on the basis that if I were to sell the beast and buy a newer one, the cost of a decent top end overhaul would be but a fraction of the depreciation of a newer vehicle....
MY99 RR P38 HSE 4.6 (Thor) gone (to Tasmania)
2020 Subaru Impreza S ('SWMBO's Express' )
2023 Ineos Grenadier Trialmaster (diesel)
Bookmarks