Oil Dilution Effect and Sound

[Captain Orso]

I'm sure you used to hear a pump running if you flipped and held the oil dilute switch upwards. Now I hear nothing.

Has anyone else NOT heard this?

Also, how long should you have to hold the switch to start to see effects in the oil pressure at an ambient temperature of -5°C?

I'm holding it down for like 1 to 2 minutes and only seeing PSI drop from 200 indicated (maybe it's higher, but the indicator only goes up to 200 PSI) to about 175, maybe 150 after the full two minutes. But that seems like it might be more from the engine temperature raising, and not oil dilution.

[grafspee]

You should expect significant oil pressure drop within 1min of diluting, alowing for 15c oil temp take off.  -5c is very cold for those engines and even diluted you won't get low oil pressure, warming up oil to 15c is required to oil dilution done it's job.

Edited August 4, 2023 by grafspee

[Art-J]

I honestly don't recall the diluter pump ever to make any sound, even in 1.2.xx-1.5.xx era. Booster pump and primer - yes, diluter - no. Need to search some very old youtube videos to confirm I guess!

Moreover, as discussed recently in the other thread, its seems to be non-functional in the Mustang now after the cooling system revisions. At least I haven't noticed it doing anything two or three OB version numbers ago (while it used to drop the pressure VERY effectively long ago). Would have to test again in the latest version.

[grafspee]

2 hours ago, Art-J said:

I honestly don't recall the diluter pump ever to make any sound, even in 1.2.xx-1.5.xx era. Booster pump and primer - yes, diluter - no. Need to search some very old youtube videos to confirm I guess!

I can confirm as far as my knowledge reach, oil diluter has naver made any sound.

Edited August 4, 2023 by grafspee

[Captain Orso]

Thanks for all the answers guys! 

The P-51D was the only thing I flew for nearly four years when I first got into DCS on the 14th of February 2015  .... ahem 

I know that at one point I wanted to see a winter map and set up a mission in winter. And because I was kind of a purist, of course I did a cold start... a very cold start in this case. And I know I used Oil Dilute, and I recall it having worked, but I'm fairly sure that I didn't have to hold the switch for 2 minutes straight to achieve this.

Maybe I need to use a stop watch to get more exact timings