Engine gauges do not match tool tip numbers

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Hook
Master Sergeant
Posts: 1358
Joined: 31 Dec 2012, 01:38
Location: Bonham, Texas

Re: Engine gauges do not match tool tip numbers

Post by Hook »

Thanks, Scott.

I've noticed that no matter how cold it is outside, the oil temp hits 40 F in five minutes, even if the oil temp starts at ambient. I need to test this more but that's how it seems at the moment, so don't take this as gospel. Typically the aircraft is ready to fly, oil temp around 75 after about 15 minutes total.

The documentation I've found says cruise PSI should be 30-60. If the gauge is adjusted to read accurately at 40, the top of the green arc is at 54 PSI. This is with a 0.6 multiplier. With a 0.54 multiplier the gauge reads at the top of the green arc at 60 PSI but is off at 40. This would make for a really weird nonlinearity scale for the gauge. Stock "multiplier" is 0.5 (divides by 2). I saw one time in very cold weather where my oil pressure was 54 at 2000 RPM in cruise and the only way to get above that would be to increase RPM which would put the oil pressure above 54 until the oil warmed more.

I did some extreme cold tests (-28 F / -33 C) starts, was even able to get the engine started without having to use auto-start. Since this was for testing only, I pushed the throttle to full right after starting rather than waiting for the oil to warm up. I saw oil pressure at 80 PSI once. After maybe 15 or 20 minutes of tests I noticed my formerly low hour "excellent" engine was now down to "good". :D Good job, A2A! :D

I haven't seen low oil pressures in any kind of normal flight, and the code indicates it only happens when there are problems. The low pressure scale isn't too critical but the high scale does seem to be from the above paragraph. I'd be interested to know at what oil pressure the problems happen. I've seen the code in damage.xml that sets a variable, but that variable isn't used in the xml code, so I assume it's somewhere in the dll file. High oil temperatures aren't producing lower oil pressures from what I can see.

Overall this has been some excellent work on A2A's part. Thanks.

Hook

Hook
Master Sergeant
Posts: 1358
Joined: 31 Dec 2012, 01:38
Location: Bonham, Texas

Re: Engine gauges do not match tool tip numbers

Post by Hook »

Hook wrote: 29 Jan 2020, 11:19I've noticed that no matter how cold it is outside, the oil temp hits 40 F in five minutes, even if the oil temp starts at ambient.
I just figured this one out. No matter what the outside temperature, the oil temperature starts at a minimum of zero F. This is probably a good thing. :D The oil temperature will go down over time if the OAT is below zero F.

Pressing Cold Start does not reset the oil temperature. Reloading the aircraft will produce the zero temperature, and saving the flight and loading it will also do this.

Hook

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