Monroy fuel tanks

[Will.iam]

On 11/8/2022 at 10:53 AM, 201er said:

Or when there isn't enough runway or you want to take a lot of friends or you want to transport a baby elephant

Baby elephant?!? Damn, fuel is not the issue here. 

[Will.iam]

I too have the extended tanks and even though it says 104.6 i have put in 107 gals before. I kept looking under the wing for a leak but never found one and even then i could burp out air i just got tired of toping off. At flying LOP 9.5 FF that’s 10 hours with a 45 min reserve! I joke i can fly anywhere in the lower 48 states non-stop from my home airport by the dfw area but it would be just me in the plane. The other added bonus is i tanker extra fuel when i find a cheap price airport and before the astronomical rise in fuel, i had managed to store 100 gals in 2 55 gal drums that i used up this summer and fall when the prices were $6-$7 per gallon i was using $3.5 per gallon 100ll from my barrels. Now the price needs to come down again so i can replenish my barrels. Might have to do it before G100UL starts effecting 100LL prices soon. 

[Pinecone]

5 hours ago, rbp said:

thats 100 minutes of flying time

Almost 3 hours at cruise for me.

 

[Ulysse]

Do you get new fuel gauges or recalibrate them ?

[Schllc]

4 minutes ago, Ulysse said:

Do you get new fuel gauges or recalibrate them ?

Not sure about all models but the two (ovation and an acclaim) I had with monroy tanks, came with a supplement to the POH that explained how to read the gauges.  It was something like when the gauges read 27 you actually had 34…

I gave up trying to figure out what I actually had based on the gauges, and used the totalizer. The challenge is to log when you add fuel because if you lose track the only way to get a baseline again is to fill up and start over. 
 

[Pinecone]

I plan on calibrating things for a dip stick and both the wing gauges and the fuel gauges.   

As a rough wag, I ran one tank to the 27 mark and it was about 31 - 32 in the tank.  But I could see 34.  I have to look for that addendum to the POH.

I figured I would calibrate full to the original fill ports to have a lower baseline than totally full to get things back in line.

[1980Mooney]

5 hours ago, Ulysse said:

Do you get new fuel gauges or recalibrate them ?

There is no way to accurately recalibrate the senders. - or replace them.  Because of the dihedral wing, the Monroy extended range tanks which are further out are therefore slightly higher than the main tanks (the extended tank flows into the main tank).  If you fill the main tank and extended range tank each to the lip, the height of fuel from fuel pick-up to top of the extended tank is greater than the range of the fuel sender.  First you will burn some fuel off while the fuel level remains above the "full limit" on your sender.  In my J, when I have actually flown full fuel, it seems like I burn at least 6-7 gallons a side (maybe more) before the gauges even budge off of full.  I have the 18 gallon extended tank - if you have speed brakes it will be 15 gallons. 

Second, at some point your gauges will read right (once the level is below the connection to the extended tank).  I was told that they gauges are accurate when the gauges are at half full.  So if your K is the same then the gauges read right when you have about 19 gallons or less on each side.  But between half (19) and full you could have up to another 34 gallons (total of about 53 gallons per side or about 105 gallons total).  It is not linear and it cannot read a drop in the top approx 5+/- gallons a side when completely full.

 

[carusoam]

For changing dimensions of the fuel tank system….

It may be helpful to use Ceis fuel floats…

The digital floats can be calibrated at several points…. One gallon at a time…

Most LBs fill a single volume in front of the main spar… their speed brakes were moved outside of this volume…

Many M20Ks have their extended tank volume, behind the spar… (as pictured in 1980’s post)

A few Ks have additional tanks outboard for overflow issues….

A couple of M20Ks have box outs built around their speed brakes…

Some Ks have the goofy flapper valve still… where LBs have a decent o-ring….  

+1 for the Monroy extended tanks and Ceis digital fuel floats…

PP thoughts only, not a mechanic…

Best regards,

-a-
 

 

[Pinecone]

Flapper valves are not due to leakage, but in case the cap departs.

If the fuel cap leaves the aircraft, the low pressure on the top of the wing will suck the fuel out of the tank.

I do wish I could have the flappers removed on my 252.  The Monroy fillers do not have flappers.

[FlyingDude]

I made a lookup table with the height of fuel level in both tanks and corresponding quantity by completely emptying them and adding 4gl at a time and measuring the levels. So I measure the amount with a stick before flying. During flight, I go by jpi totalizer. I take the level gauges seriously only once they've dropped below 16gl on each side: that pretty much corresponds to fuel level right at the connection bulkhead nipple... YMMV.

 

[Will.iam]

On 11/14/2022 at 1:30 PM, 1980Mooney said:

There is no way to accurately recalibrate the senders. - or replace them.  Because of the dihedral wing, the Monroy extended range tanks which are further out are therefore slightly higher than the main tanks (the extended tank flows into the main tank).  If you fill the main tank and extended range tank each to the lip, the height of fuel from fuel pick-up to top of the extended tank is greater than the range of the fuel sender.  First you will burn some fuel off while the fuel level remains above the "full limit" on your sender.  In my J, when I have actually flown full fuel, it seems like I burn at least 6-7 gallons a side (maybe more) before the gauges even budge off of full.  I have the 18 gallon extended tank - if you have speed brakes it will be 15 gallons. 

Second, at some point your gauges will read right (once the level is below the connection to the extended tank).  I was told that they gauges are accurate when the gauges are at half full.  So if your K is the same then the gauges read right when you have about 19 gallons or less on each side.  But between half (19) and full you could have up to another 34 gallons (total of about 53 gallons per side or about 105 gallons total).  It is not linear and it cannot read a drop in the top approx 5+/- gallons a side when completely full.

 

I don’t remember my outer tanks filler cap being that far behind the main tank filler. Will have to look closer next time filling up  

[NotarPilot]

Does any know how much the kit weighs? I really want his but don’t want to lose too much useful load.

[Pinecone]

It shouldn't be that much. Some sealant and two caps and hardware.

[NotarPilot]

8 hours ago, Pinecone said:

It shouldn't be that much. Some sealant and two caps and hardware.

I expected more hardware than that. There isn’t any “aluminum box” that goes in the wing? It just uses the existing wing structure?

[PhateX1337]

On 11/10/2022 at 12:12 AM, Will.iam said:

I too have the extended tanks and even though it says 104.6 i have put in 107 gals before. I kept looking under the wing for a leak but never found one and even then i could burp out air i just got tired of toping off. At flying LOP 9.5 FF that’s 10 hours with a 45 min reserve! I joke i can fly anywhere in the lower 48 states non-stop from my home airport by the dfw area but it would be just me in the plane. The other added bonus is i tanker extra fuel when i find a cheap price airport and before the astronomical rise in fuel, i had managed to store 100 gals in 2 55 gal drums that i used up this summer and fall when the prices were $6-$7 per gallon i was using $3.5 per gallon 100ll from my barrels. Now the price needs to come down again so i can replenish my barrels. Might have to do it before G100UL starts effecting 100LL prices soon. 

Out of curiosity, when you say you were looking under the wing for a leak, do you mean overflow out the drain hole, or truly a leak/weep from some seals? Assuming the former, but I'm working through an issue more related to the latter, so just curious.

[1980Mooney]

On 11/15/2022 at 8:08 PM, FlyingDude said:

I made a lookup table with the height of fuel level in both tanks and corresponding quantity by completely emptying them and adding 4gl at a time and measuring the levels. So I measure the amount with a stick before flying. During flight, I go by jpi totalizer. I take the level gauges seriously only once they've dropped below 16gl on each side: that pretty much corresponds to fuel level right at the connection bulkhead nipple... YMMV.

 

Right. That is half full on the standard tanks - and that is when the fuel gauges should read right. 

Edited December 18, 2022 by 1980Mooney

[hais]

On 11/14/2022 at 7:34 PM, carusoam said:

The digital floats can be calibrated at several points…. One gallon at a time…

Is this up to 89, 102 or 130 gallons capacity? 

[jetdriven]

On 11/7/2022 at 11:01 AM, 201er said:

 

NJ to Texas, Caribbean, Canada, Denver to NJ, and loads more.

Ive flown over 5hrs with a 54 gallon airplane. 6:20 I think it was.

[Niko182]

I did 5:30 with the 105ish gallon tanks and used 64 gallons. I couldn’t imagine using another 30 ish gallons And still having legal reserves. Especially with the Monroys I’d have over a 11 hour endurance while still having VFR reserves. It’s crazy how far these planes can fly.

[carusoam]

33 minutes ago, hais said:

Is this up to 89, 102 or 130 gallons capacity? 

As long as the Ceis floats are allowed to follow the fuel level… they work incredibly well… even if there are oddities with volume vs. height that some Mooneys have…

For modern Long Bodies… 130 gallons with nothing inside the tanks… optimal!

If interested… we can invite the Ceis guy.  @fuellevel  

Best regards,

-a-

[Justin Schmidt]

On 11/5/2022 at 6:31 PM, MikeOH said:

Ok, apparently this is a popular/desired STC.  However, the heretic in me is curious as to why?  My stock F has 64 gallon tanks, LOP, that's like 7+ hours to tanks dry.  No friggin' way I'm sitting in the plane for 7 hours!  I think my longest flight has been 4 1/2 hours and I had to be pried out!

So, honest question:  How many of you fly legs OVER 5 hours?  (That's a flight at 10 gph, and giving better than a 1 hour reserve).

I just can't understand the popularity of spending north of 10 AMU so one can stay in the plane for 11 hours at a 'stretch' 

 

Options, it gives us options!

I enjoy very long legs, flying is a high I don't want to come down from...because I have to then see people haha!

[Justin Schmidt]

On 11/5/2022 at 7:10 PM, FlyingDude said:

Was trying edit my previous post but it got deleted.

The gist: in aviation, we get stuff, because we want it, not because we need it.

How many of us "need" their Mooney? Seriously?

 

ME I NEED my Mooney, you truly don't understand until you are down for 6 months and counting for OH (Not all from OH, started with work in the Avionics then Annual then turned to an OH

[Justin Schmidt]

On 11/14/2022 at 5:02 AM, Schllc said:

Not sure about all models but the two (ovation and an acclaim) I had with monroy tanks, came with a supplement to the POH that explained how to read the gauges.  It was something like when the gauges read 27 you actually had 34…

I gave up trying to figure out what I actually had based on the gauges, and used the totalizer. The challenge is to log when you add fuel because if you lose track the only way to get a baseline again is to fill up and start over. 
 

I forgot to reset my totalizer once, I refuled (ended up more than I needed) at OSH and that was an interesting climb.

[Ibra]

I love having 100USG of Avgas burning 6GPH LOP at 120kias  yes to sit +12h inside Mooney you need to have devil's a***  I did 7h with someone and we become best friends 

Also the advantage down here on this side of the Atlantic, is we have Avgas fuel prices ranging from Jersey (EGJJ) at 7$USG to Almeria (LEAM) at 20$/USG

Having Monroy Long Range fuel help smoothing the bills and avoids having to make unplesant stops to fuel with extra hassle (opening hours, handling, customs...), I did spend the whole day on phone once trying to spell "A.V.G.A.S": "Alpha Victor Golf Alpha Sierra" not "Julliette Echo Tango Wun" 

Edited May 5, 2023 by Ibra

[Fly Boomer]

6 hours ago, Ibra said:

Also the advantage down here on this side of the Atlantic, is we have Avgas fuel prices ranging from Jersey (EGJJ) at 7$USG to Almeria (LEAM) at 20$/USG

Yikes!  I will never complain again.