The oil pressure guage on my Cat D3G 2005 (3046T 6 cyl engine) normally runs at about 40 to 45 psi. Recently it has been running at 60 psi at start up. After warm-up, it settles in at about 50 psi. At start-up, I have seen the pressure guage spike to over 80 psi and then swing back to 60 psi. Information I have gathered points to a sticking oil pump bypass valve. Is there a way to resolve this without replacing the oil pump? The machine has 2100 hours on it.
I would hook a high quality mechinical gauge up and recheck the engine. If i rember correctly it has a external relief on the left side of the engine.
The relief valve is on the left side but I was of the mind that there is also a bypass valve which is intergrated into the oil pump. By the way, where is the oil pump located on/in the engine?