When i built this engine pressure was around 60+ on the highway, and never less than 10 at idle in gear after the highway. As the miles stacked up (38,000 and change on it as of now), the pressure got less, which is expected. It averaged about 40 highway and would flicker the light at idle after the highway. Recently it blew a heater hose and it emptied nearly all the coolant in the system and strangely after fixing that, my oil pressure increased by about 10psi and doesn't flicker the light anymore. Im running 15w40 in the summer, 10w30 in winter. I daily drive this 100 miles a day on the highway for work, 3000rpm at 70mph, so i think the thicker oil is warranted.
The coolant level was low and the car was actually not cooling properly. After fixing the hose and adding a full load of new coolant, the engine is running cooler and therefore oil viscosity is higher. Thicker oil, more pressure. My theory.
Seems legit. I know the hotter they get, the lower the pressure so I'd keep an eye on it and see if it remains consistent again.
The coolant level wasn't low prior to the hose bursting. It was tip top full. Psi was 40 or less at highway rpm fully warmed up before the hose blew, and now it's 50 after. That's the weird part. Nothing changed. Only thing that happened was it overheated. I wonder if the timing cover got tweaked and the relief valve is stuck or is now unstuck. And this happened immediately after. I fixed the problem less than an hour after it happened and that's when I noticed the psi change.
Perhaps it got hot enough to dislodge something? Maybe something was partially clogging the oil pickup and now it isn't. Nothing in the oil filter?
The oil filter is partially plugged from the deposit stuff the extra heat made come loose in the engine. Change the oil and filter and the pressure will drop back down to normal.
no deposits in engine, its sparkling clean. oil is still nice and brown has less than 2000 miles on a recent change.
With a overheat condition like you had and if your running a non mechanical oil gauge then I have seen the pressure senders change there resistance due to the overheat session. I have seen them read higher or lower. Since this has taken place it's imperative that if you do not have a mechanical gauge that you install one so that you 100% know what you have.
