mooniac15u

Were you bidding on the 201 over in Newark (KVTA)?

Just saw this on FaceBook. Seemed relevant to this discussion.

That plane doesn't have a J cowl it does seem to have the 201 windshield and some kind of cowl closure mod. http://skywagons.com/_aircraft_for_sale/N9393M/N9393M.html

You can order one from Shutterfly for $5. https://www.shutterfly.com/photo-gifts/mouse-pads?categoryCode=1093734

pH 10.9 is basic, not acidic.

That's just because the the probes function differently for the temperature gauges. Increasing temperature causes increased resistance. In the other probes lower values cause lower resistance. So, if you increase resistance in all the circuits the temperature gauges will read higher and all the others will read lower.

Since each gauge grounds through its own sensor, if all the gauges are fluctuating then the main airframe ground back at the battery is a good place to start. Even a small amount of corrosion where the cable attaches to the airframe can cause interesting behaviour in those gauges.

Is it a fluctuation that then returns to normal or a sustained change?

I talked to my contact at the LHQ FBO. He told me that Mooney sat on the ramp for many years. It was recently purchased by someone on the field for parts. They apparently have two other airframes and they are using all three to assemble one airworthy Mooney. He said the portion of the airframe sitting on the ramp is for sale.

I believe naval jelly contains phosphoric acid rather than hydrochloric acid.

No worries. Just to clarify I said, "best money I ever spent on my M20D." When I bought the plane it already had all the LASAR speed mods including the 201 windshield, recent paint & interior, 6-pack instruments, IFR GPS, engine monitor, and upgraded yokes. I didn't have much to upgrade. I spent a lot of time flying at night and the generator sometimes wasn't up to the task. The alternator kit plus installation was under 1 AMU at the time for a high quality product. So, for the quality of the product at the price point and the upgraded performance and reliability at night I was completely satisfied. Other "big ticket" things I spent money on for the M20D were a new hub for the prop AD and a couple of new cylinders. Neither of those produced any noticeable improvement in spite of the many AMUs invested.

Not quite what I said but yes, really. It's nice that you have a wish list but it's not my wish list so imagine that, different people can find value in different things.

The generator to PP alternator conversion was the best money I ever spent on my M20D. The alternator supplies lots of power at low RPMs compared to the generator.

I'm not sure where that diagram is from but here's the schematic for the cluster gauge for the OP's S/N. You can see that there is power connected across all the gauges and then each has an individual ground that connects to the sensor on another part of the schematic. The fuel gauges have a second connection to the annunciator panel for the low fuel lights. There is no common ground for the cluster. I suspect that the ground in your diagram may be for the lights. The cluster gauge was not lighted in 1981.

I was referring to the OP who has now started two separate threads on why J's should be vintage.

I sense some J-envy...

The J was the first Mooney model to use sections of Part 23 for its certification. All previous models were certificated entirely under CAR 3.

It's a J thing. You wouldn't understand.

On the J each of the gauges grounds through the sensor.

I had the 201 windshield on my M20D. It was a bit tight but I never had an avionics shop suggest that that windshield might need to come out for access. I'm curious. Has anybody here with a 201 windshield on a vintage Mooney had to have their windshield pulled for avionics work?

What brand of LEDs did you use for your wing tips? I'm interested in switching to LEDs but I haven't seen an STC for the J.

Last time I looked Whelen's STC didn't list the M20J. Did you do this conversion with a field approval?

N201EF has a colorful history. http://airflightdisaster.com/index.php/flying-tigers-inspection-fraud-scheme/

That looks like it might be at least partially a grounding issue. With the M20J a bad ground will cause the two temperature gauges to read high and the rest (oil press, fuel press, fuel quantity) to read low. Since it seems to be affecting multiple gauges it could be the main airframe ground.

The AMOC actually requires a fuel check before each flight. I had the old style caps for 8 years and also never had a problem with water in the tanks.