LOW FUEL L-R warning light

[Aerodon]

 I had these Eaton annunciators made to replace the Mooney annunciator panel. The Engine/Engine is linked to the JPI and will give a low fuel warning.  I kept the Vac Hi/Lo because I still have a vacuum pump for the speed brakes.

[Pinecone]

On 1/4/2026 at 5:23 PM, Aerodon said:

I don't think that's the right way to do it.  Next time you run it down to 'the light', then drain the remaining fuel out to see how much was really left. 

My 252 has 104G useable, but i am told I can get as much as 109G in the tanks.  There is no 'definitive' full mark, although when I calibrate the JPI gauge I will keep notes of exactly how much fuel to bottom of filler neck, top of filler neck etc.

Aerodon

It depends on how patient you are.  I find I can get 55 gallons a side, but it takes waiting a good bit of time to get the last few in.  When I calibrated some dipsticks, I could hear air bubbling from the main tanks back to the Aux even when I was over 52 gallons in the tank.