Oil filter housing - relief mechanism failure.

[Alan Williams]

On my 76 p-model S/N 246 the rear engine oil fiter housing relief plug had come loose. We replaced that housing with a new continental part and about 10 hours later oil pressure dropped from 50 lbs to 32. Hmmmmm?
Cold pressure in the green, Operating temp gave 32 lbs or minimum spec. What to do then. Put on another twenty hours with no change to low oil pressure.
Then, R/E waste gate actuator began to act up masquerading as a fuel vapourization issue. At 16,000 ft manifold pressure dropped to 20 inches and returned to 28 in with descent . Purging of fuel system solved the problem for about two hours.
Finally after much pressure checking decided problem needed to be addressed. Engine was dissasembled. First off, the new oil filter housing. Oh Oh, look, the relif spring basket is hanging by two of its three legs and the fibre disk is GONE. Only one way for it to go but the question is how far. Found it jammed by the overhanging gasket at the entrance to left hand engine case gallery acting and looking like a butterfly valve in the hole. The oil pressure port is about 10 inches further along the case so now we know where the oil pressure went.
Was there any intermal damage to the engine. None at all.
However now we have a 900 hour factory reman engine which was running superbly and looking for all the world like it would go to TBO IN small pieces because a factory new part failed.
Question? Should the manufacturer bear some responsibility for the costs to reassemble.