What can cause overly high oil pressure?

[marco]

Its already on order along with another 5lt of oil. Pricing up the turbo oil pressure regulator and required fittings it would be a couple of hundred quid, so at that price I might do it anyway.

 

[marco]

Right. Swapped oil for 5w30 and changed filter. Still seeing over 5 bar at cranking. Thought it could be iffy pressure sensor so hooked up an old mechanical sensor and it is reading the same. So pretty sure I am seeing true readings. Not sure what to do now, either I pull the engine to investigate, or I accept it has high oil pressure and just run it. If I go for the latter will need to fit a regulator for turbo feed, but that isn't that unpalatable. Anyone got any thoughts?

 

[JoeLanger]

Mines about 8 bar with 15w40 (I'll be trying 10W next to reduce this) when cold, so 5 isn't that high?
Maybe check your lines again to make sure that there's no blockages

 

[marco]

Its 5 bar at cranking though, so once I get it actually running it will be off scale. If anything the readings have increased since changing the oil (sensor actually reading closer to 7 bar), but i have also replaced the sensor line with AN fittings rather than push fit so assuming I have less pressure loss in the line. There is plenty of oil getting to the turbo so feeling content there is flow there, Is there a way to confirm flow to the rotors without pulling the engine? The last readings were taken with plugs out to see if there was any kind of passing between rotor housing and oil system- made no difference so I am sorta happy it isnt that. I guess it 'could' be clogged with assembly lube etc, but would think I have flushed that through now.