Jump to content

M20E Tank Dipping


Recommended Posts

Think of all of the disclaimers that all of our present and future attorneys might scream...

 

A week or so ago, I filled my right main tank 5 gallons at a time while marking on a dip stick. Attached is a photo of that stick along side a measuring tape.

 

Of interest to me (that I now think I should have anticipated) the last three gallons of fuel are about the same dimension as the middle five gallons. It appears that the tanks are pretty linear (dip length-wise) until nearly topped.

 

Don't use this for your aircraft, just a discussion point.a299f2c875db81031081dd716e7416ab.jpg

 

 

Sent from my iPad using Tapatalk

Link to comment
Share on other sites

Started with (what I would call) minimal. About 2.5 inches of fuel which turned out to be 8 gallons - based on how much to took to fill to 26 gallons.


Sent from my iPad using Tapatalk

Link to comment
Share on other sites

1 hour ago, 211º said:

It appears that the tanks are pretty linear (dip length-wise) until nearly topped.

That is my observation. I bought a Fuel Hawk a few years ago and then added fuel a gallon at a time until I had a conversion chart. It is more accurate than my MVP-50.

Link to comment
Share on other sites

I still dip mine every flight. The JPI is accurate with in 1gal per full tank. I think that's acceptable. 

I drained all I could from the wing sumps, then added fuel and made a wooden stick.

-Matt

  • Like 1
Link to comment
Share on other sites

22 hours ago, MB65E said:

I still dip mine every flight. The JPI is accurate with in 1gal per full tank. I think that's acceptable. 

.........

-Matt

Me too.  That and a watch are my best fuel management tools.

  • Like 1
Link to comment
Share on other sites

One data point. I ran my M20E right tank to the point where a loss of fuel pressure could be seen and then switched (my son in the right seat was nervous about actually letting it quit). Presumably bubbles were starting to get sucked in. Back on the ground I could barely see a little fuel when looking in the through the top. The inlet and screen are about an inch above the lowest point so with the dihedral angle that put the surface of what I'll call the "unusable pool" just about at the level of the lowest point of the outer section of the fuel tank. 

Now I know that if I can only see a little bit its about to run out, even though there's some out of sight in the inboard compartment.

I think I'll remake my dip stick. I'll run it down to the point of losing fuel pressure then land and fill it to the point where I can just touch my stick straight up and down. That will give me the usable fuel number for the bottom of the stick. Then I'll fill it until fuel is just touching the bottom of the outboard bulkhead and that will be my first mark. From there on four gallon increments until its full. I haven't decided whether to use pencil, tiny chisel, or woodburning to make my mark. Pretty sure sharpie will dissolve away in gasoline.

Link to comment
Share on other sites

4 hours ago, pinerunner said:

I haven't decided whether to use pencil, tiny chisel, or woodburning to make my mark. Pretty sure sharpie will dissolve away in gasoline.

You can do a "reverse dip" stick, too, where you put the end of the stick just touching the top of the fuel and measure to the bottom of the filler neck.  This prevents putting the stick into the fuel very much and also avoids touching the bottom of the tank (and potentially any sealant areas).    This may not work great at night, or in low light, though.

Link to comment
Share on other sites

One data point. I ran my M20E right tank to the point where a loss of fuel pressure could be seen and then switched (my son in the right seat was nervous about actually letting it quit). Presumably bubbles were starting to get sucked in. Back on the ground I could barely see a little fuel when looking in the through the top. The inlet and screen are about an inch above the lowest point so with the dihedral angle that put the surface of what I'll call the "unusable pool" just about at the level of the lowest point of the outer section of the fuel tank. 
Now I know that if I can only see a little bit its about to run out, even though there's some out of sight in the inboard compartment.
I think I'll remake my dip stick. I'll run it down to the point of losing fuel pressure then land and fill it to the point where I can just touch my stick straight up and down. That will give me the usable fuel number for the bottom of the stick. Then I'll fill it until fuel is just touching the bottom of the outboard bulkhead and that will be my first mark. From there on four gallon increments until its full. I haven't decided whether to use pencil, tiny chisel, or woodburning to make my mark. Pretty sure sharpie will dissolve away in gasoline.


Paint stick and fine tip sharpie. It has not devolved in 5 years.


Sent from my iPad using Tapatalk
Link to comment
Share on other sites

I did likewise when recovering my aircraft from the mechanic.  Left tank looked dry so we added 5 gals at a time.  Turned out to have 6 in it already, so may stick is 6 low.  No problem, I'll stick every time from now on.  I'd rather have a low estimate than none at all, especially given how utterly useless my fuel gauges have turned out to be.

  • Like 1
Link to comment
Share on other sites

On 5/27/2017 at 5:18 PM, 211º said:

 

Think of all of the disclaimers that all of our present and future attorneys might scream...

 

A week or so ago, I filled my right main tank 5 gallons at a time while marking on a dip stick. Attached is a photo of that stick along side a measuring tape.

 

Of interest to me (that I now think I should have anticipated) the last three gallons of fuel are about the same dimension as the middle five gallons. It appears that the tanks are pretty linear (dip length-wise) until nearly topped.

 

Don't use this for your aircraft, just a discussion point.a299f2c875db81031081dd716e7416ab.jpg

 

 

Sent from my iPad using Tapatalk

 

If anyone can post a picture like this for 32gal tanks, it would be awesome!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.