Hi all,
I recently bought an old truck that has a stock 1986 305 L98 TPI motor in it (unknown if ever rebuilt) . The engine runs smooth and quiet with no knocking etc.

I have noticed that the oil pressure runs at around 40 psi on start up then at around 10-12 psi at warm idle and 30ish at running. I recently replaced the oil with a 5w-40. I hooked up a mechanical Gauge that likely isn't calibrated but it showed similar movement to what I was seeing on the dash gauge.

The engine temp ranges between 230 when the aftermarket fan clicks on to push it back to 180 or 190.

Should I be concerned about anything or is this pretty normal. My internet research seems all over the board with info.

 

Just me here, but I'd run a bit stiffer oil, see if you can adjust the fan control down some. Maybe run Rotella 15w40 in warm weather. But it will run a long time as is.

 

A stock TPI will run fairly warm..The fan cut-in temperature is right around 230°F. Reprogramming a custom PROM for the ECM can alter the fan operating parameters. Another, almost as easy method is to install a secondary temperature switch as both a backup to the factory system and as a means to alter the operating temperature.



One wire to parallel the ground to the fan control relay is all that is necessary. Someting like the AutoMeter 3246 is just about the right temperature rating.