Quote:
Originally Posted by ngoma
Dr. Dan suggested to me to a) try heavier weight oil,
|
I think that is backwards, maybe he misspoke. True that heavier weight oil would raise the pressure *after* the system already primed and running, but it would have a negative impact on length of time to get oil circulating and build initial pressure. Lighter weight oil would help with that and heavier would hurt. 15W40 is too heavy for sure especially in cooler months.
0W30, 0W40, 5W40 (all synthetic) seem to be what works best. Overfilling or at least keeping the sump at the full mark does seem to help too.
Tom Bryant's favorite is 5W30 Mobil 1. YMMV, but the important part seems to be the cold number. 0W or 5W best.
Quote:
Originally Posted by ngoma
Important Q for science: ---What is the mechanical oil pressure at startup when the low oil press light is lit?--- That will help us ascertain whether it is actually causing a problem or not.
...
Your mechanical oil press gauge will tell us what is really happening upon startup rather than relying on the dummy light.
|
Do I remember right that others have talked about something happening to the oil pressure switch (for the idiot light) that can delay its turning the light off even after pressure builds? Something about the diaphragm inside the switch leaking so that oil moves to the backside of it, then it obstructs the switch from opening.
As you said, the mechanical gauge's reading will show that if there's something wrong with the switch.
One more question: is this something you are noticing only now after doing the internal engine refreshing, and was not a problem before that work was done? Or has this engine always done this while you have had it?