Oil Pressure Puzzle

[john erbe]

Hoping someone with 6.9 could solve a mystery problem of inconsistent oil pressure by taking note of a couple of items on theirs when they check their oil level, on a car that had been sitting overnight and report back. Do this without starting the car1) when you removed/unscrewed the cap did you hear that you had broken suction on the resevoir ie there had been a vacuum and (2) what was the oil level reading on the stick. Have a nagging issue with oil pressure and now that I've started to remove hoses and fittings from sump have come up with theory as to why this problem had'nt been there before but only after after they replaced a cracked sump. Thanks

 

[John S]

Are you getting the vacuum in the reservoir tank, or from the sump? How much 'vacuum' are we considering when you hear air suck in? Or can you feel the resistance when you take the cap off?

 

[john erbe]

Can't feel resistance but can hear the air suck-in.

 

[Styria]

Hi John, it would seem to me that something has gone astray in the course of the sump replacement. Generally speaking, as best as I know, there sometimes may not be all that much difference in the oil levels prior to start-up, or after the oil has attained operating temperature.

I don't think that the hoses can get mixed up when refitting new units, or changing the sump, but I would closely look at the various hose fittings on the outside, but more so on the inside, of the sump. I think you need to sort this properly and quickly - the last thing you want is an engine that's starving of oil - it does not take long to run the bearings. Be watchful ! Regards Styria

 

[john erbe]

Possible cause found, at least I think so. In comparing the fittings to those of a spare engine discovered that while the o-rings were all present, the large rubber seal on the forward tube was missing.