ItzFitzyFitz

I have an 83 12a BP and live just outside of NYC (40mins) I notice when I drive my rx7 it doesn’t want to reach operating temp. The needle sits just above the C and will sometimes drop when driving. Another question I have is about my oil pressure and that at idle it will sit just below 60 and when I drive it it will jump to around 100 and drop down to about 80 is this normal?

Ckforker

Have you measured the coolant temp in different spots like top and bottom of radiator? Maybe a stuck open thermostat.

On oil pressure, did you recently change the oil and filter? I've experienced odd pressure from a bad filter. I'm sure others will chime in.

ItzFitzyFitz

no I have not measured the temps for the top and bottom of the radiator

i did change and replace my oil and oil filter but was still occurring before I replace them

GSLSEforme

Are you running a beehive oil cooler or a fmoc or something aftermarket?
Radiator original type or aluminum?
What type and temp thermostat?
Electric fan or oe clutch fan?

The original water and oil cooling systems that came in these cars are very efficient at radiating heat.
Many ditch the oe radiator for an aluminum unit that can actually overcool the engine not letting it get to the temperature it needs to run properly.

I don’t live in your area but using my car as an example when driving at temps hovering about freezing I can see both the coolant temperature and the oil pressure gauge readings change slightly as the thermostats in each of these systems keep the engine at optimal temperatures. These type of fluctuations are normal.

t_g_farrell

iTrader: (1)

Its a BP, so as GSLSEforme says, we need to know details about your setup. Can't be stock cause of the BP. I suspect either no tstat or poor design of the cooling system. Those oil pressure fluctuations sound kind of normal to me. I bet that BP wasn't built to be driven in the winter cold no matter what the PO said.

j9fd3s

iTrader: (3)

oil pressure is right where you want it.

you might check to make sure there is a thermostat, or that the bypass is plugged.

ItzFitzyFitz

i think the oil cooler is stock
Radiator original
I need to check if it has one cause that might be my problem
oe clutch fan

ItzFitzyFitz

i will check if there is a tstat

LongDuck

When it's cold, grab the fan blade (*engine not running!) and give it a spin. It should freewheel fairly easily and smoothly. If it's hard to turn, or won't turn at all, its failed and clogged the ports which will cause it to 1) sound like a B17 on takeoff, and B) cause your engine to run cooler than normal. Combined with other things, this could be contributing to the running cool condition and is super easy to check,

tommyeflight89

iTrader: (4)

Also a note on oil pressure, the OEM sending unit can sometimes mislead you, my sending unit (original to car) began to act funny where it would show oil pressure dropping slightly (by 20% or so) while cruising. I spent a while convinced I had some sort of oil foaming issue. I replaced it with a new OEM Mazda sensor (just get from local dealer) and my readings have been consistent since. (Other than showing the typical dependence on oil temperature).