914 Oil Seepage From Airbox Intake Tube

Just look for white smoke, it is likely going to be on start and take off RPM.  Generally a small leak will not be noticeable so watch your oil consumption.  I would not operate without the cowls as they may play a significant role in cooling for your engine. 

If you have been having problems it may take some time to clear residual oil from the intake.  Be sure to check the collector can at the bottom of the turbo for signs of carbon also. (newer 914 and all 915/916 have a removable screen to clean) 

Cheers

Is there anything in particular you'd look for that would say to you, no go? My fear is damaging the turbo from lack of oil.

For instance, is an initial puff of white smoke OK, but if it persists, then shut it down for further inspection?

Hi Craig

the turbo center section is feed with oil from the oil pump when running.  White smoke indicates you are ingesting oil from the center of the turbo for one of several reasons.  First, the banjo bolt and check ball are contaminated with carbon.  This normally leads to some smoke on start up but little to no oil loss.  It suggests the ball is not sealing and this may overfill the centre section when not running due to the gravity feed of the oil.  Clean it and replace the banjo bolt and ball as they are very hard to reseal.   More serious is if the turbo return line from the bottom of the collector tank  is contaminated with carbon.  In that case oil that should return to the oil tank then begins to feed back into the hot and cold sections of the turbo.  The later will cause a volume loss and that is more serious.  Some oil burn in the hot section is not really a big deal but should not be ignored.  Oil pumping from the turbo to the intake would have me remove the oil tank on the bottom and also check the return oil line from the turbo pickup line to the oil pump scavenge rotors.  This line is stainless and can be cleaned with a tiny gun brush to remove any hard carbon if required.  With the return line disconnected from the collector tank it is easy to remove it and clear any buildup of carbon inside. 

Cheers