Long range tank question

[AlexR]

Greetings all, 

I may need to upgrade my M20C to long range tanks.  Moving to Mexico for work were I will need to tanker fuel for the flights I gotta do (MMAN to MMCZ).  Fuel stops are few and far between and landing midway will cost me 2-3hrs of filing out paperwork to refile as well as having the plane checked out by the Military, Customs, Immigration, etc.   My only concern with the Monroy tanks is I have heard it is nearly impossible to just fill the mains as well as keep an accurate track of partial fuel loads.  Would anyone that has them care to comment on this?  What is the fill procedure for just the main?  How about totally full?  Do you have to go back and forth between the two tanks with the fuel nozzle to 'top off' as the fuel settles between both tanks?  What does the flight manual supplement look like?  Any limitations/restrictions?   Any info would be most appreciated.  I have an email in to Monroy on the topic, but no response yet.

Cheers,

-A 

[201er]

My 201 came with the 64->98 gallon tank extensions. It's nice to be able to take 10+ hours of fuel but the hard part is keeping track of all of it. My fuel gauges are completely wrong so I installed a fuel flow totalizer to keep track of fuel. The only time I really know how much is in it is when it's full so I fill to full (but it limits me to 2 people).

You fill the mains first, cap them, and then the outboards. If the cap is open on the main tank and the outboard is really topped off, it could flow out the main cap hole. It only takes a few gallons until that is no longer an issue. If you want to gte 100% full, you do have to go back and forth between tanks because you top one off and while you're topping the other, the first one partially drains over. If you're willing to accpet 90%+ full, you can just do mains and then aux and done. PM me if you have further questions cause I have scans of the supplements and the info. It's pretty useless and mostly I'm figuring it out on my own though. Not sure if the same tank applies to your C model though. Good luck.

[AlexR]

201er...many thanks for the timely reply...pm sent...again, much appreciated.  -A

[Piloto]

I have the Monroy tanks on my M20J and follow a simple guideline. When the fuel level is at the 25gal tab inside the tank then I have 32 gallons on that wing which is the equivalent of a full main only. If I am doing short trips I only fill the mains. As a general rule you will have more fuel than indicated by the panel gauges from mid scale to the full mark. From mid scale to the empty mark the aux tanks are empty so the fuel indicated by the gauge is the actual fuel onboard. A fuel totalizer is handy but not a must. After a couple of fill ups you get the hang of it. I found them very reliable since there is no transfer pump to worry about.   

José

 

[Lood]

How about a good old calibrated dipstick? Empty the tanks and fill them 5gal, or any other figure, at a time, calibrating the dipstick after every 5gal. I've done that with every airplane I've owned and trust my dipstick even more than the fuel flow computer - specially with the tanks on my Mooney seeping.

[201er]

^ This is damn near impossible with the extended tanks. I've tried doing this twice already and can't get consistent results. If you fill up the main very quickly, the main fills up and barely drains over to the aux. You leave it like that a while and it levels out over time. Sometimes it won't cross flow to balance until you fly. You have to dip into the main and aux tanks separately which requires two different charts and addition. You gotta watch out that the fuel isn't moving on you at the time you do take a reading.

[AlexR]

Folks,

Thanks for all the feedback.  Based on my mission profile, these will be mandatory for Mexico.  As soon as my assignment is confirmed, I will place an order...will advise and post pictures of the install.  My main tanks were resealed by Wilmar in 2008 and are still under warranty so that should help. 

 

[RJBrown]

Get a good fuel flow meter,I had a EI FP-5L in my Rocket, that is accurate to a tenth or 2 over 100 gallons. Each time I topped the tanks I just pushed the button to reset the gauge to full. On partial fills I would enter the number off the pump. To get a repeatable full you fill the inner tank then fill the outer tank. Now with the outer cap off you remove the inner cap to vent and watch the fuel level rise as the outer tank tops the inner tank. Once full cap the inner and re top the outer. You are now full. If you are careful you can always know what is in the tanks. Even after 3 or 4 partial fills in a row I was never off more than half a gallon. The Electronics International FP-5L sells for $575 plus install and is always dead on accurate. Every time I reset fuel level in my MSE I miss the EI gauge. The thing in the new plane is nowhere as user friendly as the one in the Rocket I used to own.

[AlexR]

I have an EDM-830 backed up by a FS-450, so no problems there...thanks to all for the info.

[Carl S]

Did you get the long range tanks?