slow oil pressure build, how long is normal?

[lotusesprit1]

Is it normal for oil pressure to take 15-20 seconds to build on the first start of the day? I don't remember it doing it before the oil and filter change?

 

Oil pressure when hot and cold is normal.

 

I do have a one way valve in the filter in the as I checked the part number on the manufacturers web site, Should I change the filter or do I have another problem?

[jonwat]

Always takes a while to build up pressure after first start as the filter empties overnight & has to be refilled.

 

The low oil pressure won't do any harm as long as you sit there until it's built up to normal as there's very little gas pressure forcing the piston down the bore while you're not loading the engine. 

 

I once done a superb oil change, everything perfect, except I forgot to add the new oil.   

 

After restarting I must have sat there watching that needle sit on zero for a full minute before I realised. 

 

No harm done though.

[Sir Paolo]

Did you change oil grades? Reason is that I noticed that it takes longer for pressure to build when I switched to Fuchs Pro R from the Castrol GTX I used to run the engine in following a recent rebuild.

John, your tale of no oil following a change reminded me of another I heard, where the opposite happened. The story went that a husband was called away in the middle of an oil change, and his wife thought she'd help by refilling the oil. Thinking that the oil level should be upto the filler neck, the well meaning wife bought more oil until the engine was full. None the wiser, the husband pleased that his wife had helped, until he drove the car when it blew its oil seals.