Euro 930 Low oil pressure

Hey gang,

I have a 1982 930 Turbo. My oil pressure reads 4.5 bar and 5500 RPM. Factory specs are 5.0 bar at 5500 RPM. I verified with a mechanical guage. Strangely it seems to hit 5.0 bar at first, then drops down to 4.5.
I'm running Mobil One 10-50

I thought at first that it might be the safety pressure relief valves. However, on a cold day here in Chicago, it has no problems hitting and staying at 5.0 bar until the oil really warms up so I assume now that it's not these valves. Anyone with some ideas?

I think it would be a good idea to replace the springs for both of those relief/safety valves. I have seen those types of springs 'relax' a bit over the years, and have replaced them. You may want to make a note of the free length of a new replacement spring and later measure your 'old' ones, just for reference. In this case, half a bar, or atmoshere, about 7 psi, may be hard to come by, but if those valves are operating at all, it may be helpful to change the springs. What is your oil temp. looking like when the pressure drop from 5 bar down to 4.5 bar is noticed? You may want to remove the thermostat for the external front oil cooler and clean thoroughly, just in case anybinding or sticking is occurring. You may want to investigate whether the louvers for the front oil cooler are blocked in any way, by dirt (mud), or whether that front cooler has any damage to cooling fins. In your case any small gains in cooling will be helpful, so it may just be a matter of checking everything to be sure, including the oil filter. Some aftermarket oil filters are more restrictive that others, so a return to the factory filter may help. If you decide to remove the front cooler for inspection, a thorough cleaning, first outside, then inside with something like B-12 ChemTool would be useful in getting deposits out and returning maximum heat transfer capability back to 'new' specs.

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Warren Hall
1973 911S Targa

See your oil-airbox question -- both are directly related ... and caused by the relief valves or springs!!!

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Warren Hall
1973 911S Targa