Last night I changed by transaxle oil for some posh stuff, then I did the engine oil for the first time.
I read the clark's guide on engine oil to make sure I didn't miss somethig silly:
- remove sump tray
- remove sump plug
- remove filler cap
- remove filter
- wipe-up small spillages (hardly any)
- inspect the oil in the bowl (looked dirty but otherwise correct - was 3500 miles old, so I'd expect that)
- reinsert sump plug
- fit new filter
- fill oil (5litres to start)
- turnover and run for 2-3mins
- refill the last 500mils
- leave the second under tray in a cupboard (!)
...wow, that as the cleanest and easiest oil change I've ever done on any car ever!
I went for a spin around the bottom of the ring road and was happy to see 5 bar on the oil pressure. However after about 5 minutes the pressure dropped right down to 1 bar and I got the red light of doom. I can't lie, I nearly *hit myself! I mean, how hard is it to change some engine oil?!
Fortunately I had a second bottle of teh same oil with me so i checked the dip stick in the glow of the working under-bonnet lamp. it looked within the dipstick markers but I chucked in 500mls to be sure. It stayed low unless used the throttle to up the revs a bit. above 1500 rpm it looked about 2bar so I decided to limp home...
About half a mile later the oil pressure went back up to 4.5 bar and then stayed there. i decided to go out for a 30minute spin to make sure and after that it was fine.
Question: What could have caused this?
Is there a separate set of oil ways that open up (like a coolant thermostat), when the oil gets to a certain temperature?
Is there a thermostatically controlled oil cooler circuit? If yes, i'm surprised it emptied since I only ran the engine for 2-3mins before draining too (yeah, I know it's best to drain warm oil to get more out).
I ran the engine and topped up after the initial fill, to ensure the filter got filled with oil. Presumably 2-3mins running on the axle stands wasn't enough.
Bemused!
