Óleo no depósito de água 850 turbo

Olá, bom dia a todos no fórum, espero que você possa me ajudar? I bought a Volvo S80 850 Turbo Model 1994 in car they sold it with the oil failure in the water tank,
the car starts, according to the previous owner he says that the hit the oil filter and it was emptied on the road and from there is the fault, the head emerged and the joint is fine but I will replace it, that they rectify the head to avoid if the board was twisted, if the joint He was able to mix the water with the oil. ou onde o filtro de óleo está um refrigerador? E poderia ser perfurado e está misturado? Ou onde pode ser o mais? Obrigado pela ajuda.