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[GMCnet] gas tank capacity mystery [message #102768] Wed, 13 October 2010 02:42 Go to next message
greg is currently offline  greg   United States
Messages: 17
Registered: May 2004
Karma: 0
Junior Member
Well, after the hair-raising adventure of getting stuck outa gas while
backing down the incline last weekend,
i finally had a chance to take the coach out on the highway today.
This comes after last week's gas tank drop, leak-fix and re-mount.
the leak was only a pin-hole at one of the vent lines and everything
else looked great.
when we were done, we put in 4 or 5 gallons to start with.
After i got stuck on the hill, we put in 12 more gallons. let's say
16 total.
then i drove 19 city miles and went to fill it all the way up
so i could take notes and track the MPG.
I was shocked to see the coach take on an additional 44.6 gallons!
If the supposed capacity is 50 gallons total, then something doesnt
add up here.
16 gallons minus 19 city miles (4 gallons?) = approx 12 gallons.
so how in the world did it swallow 44.6 more gallons at the pump?
that'd be 56.6 gallon capacity tanks. Is this possible on any of the
models?
Mine is a '78 Eleganza II, and yes, the tanks look a little bulging at
the bottom.
i checked to see if anything was leaking, and nope... Everything's
tight.
(Well, OK, there's some gas smell when i come to a sharp stop,
and we were gonna check the canisters next, but i can't imagine any
significant loss here...)
So is this simply a bulging tank phenomena, and i have an unintended
"upgrade" to 57 gallon tanks?
whew! that'd be the first upgrade i didn't pay for!
Any insights appreciated..... Thanks all!
Greg
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Re: [GMCnet] gas tank capacity mystery [message #102771 is a reply to message #102768] Wed, 13 October 2010 05:40 Go to previous messageGo to next message
g.winger is currently offline  g.winger   United States
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Location: Warrenton,Missouri
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I put in 56.5 once and it was a runnin!!!!But I don't think it would run mush longer!!,,,PL
Re: [GMCnet] gas tank capacity mystery [message #102783 is a reply to message #102768] Wed, 13 October 2010 08:11 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
greg wrote on Wed, 13 October 2010 03:42

Well, after the hair-raising adventure of getting stuck outa gas while
backing down the incline last weekend, i finally had a chance to take the coach out on the highway today.
This comes after last week's gas tank drop, leak-fix and re-mount.
the leak was only a pin-hole at one of the vent lines and everything else looked great.
when we were done, we put in 4 or 5 gallons to start with.
After i got stuck on the hill, we put in 12 more gallons. let's say 16 total.
then i drove 19 city miles and went to fill it all the way up
so i could take notes and track the MPG.
I was shocked to see the coach take on an additional 44.6 gallons!
If the supposed capacity is 50 gallons total, then something doesnt add up here.
16 gallons minus 19 city miles (4 gallons?) = approx 12 gallons.
so how in the world did it swallow 44.6 more gallons at the pump?
that'd be 56.6 gallon capacity tanks. Is this possible on any of the models?
Mine is a '78 Eleganza II, and yes, the tanks look a little bulging at the bottom.
i checked to see if anything was leaking, and nope... Everything's tight.
(Well, OK, there's some gas smell when i come to a sharp stop,
and we were gonna check the canisters next, but i can't imagine any significant loss here...)
So is this simply a bulging tank phenomena, and i have an unintended "upgrade" to 57 gallon tanks?
whew! that'd be the first upgrade i didn't pay for!
Any insights appreciated..... Thanks all!
Greg

Greg,

What you have missed is the industry standard for "Refill Capacity". That is what is stated on all vehicle specifications. It allows for some amount of dead volume (what you should not normally be able to retrieve) and roughly 10% expansion volume.

You can use that unregistered capacity if you are conscientious and you really know the vehicle and the situation.

Where you smell gasoline vapor from can be an indicator of other things that need attention. If all the rubber in the fuels system has not been replaced recently, it probably should be.

As I am very careful about my fuel management, I have frequently filled with 54+ gallons. I never do this close the the end of day or on a hot day. It makes that tank look bad, but the next tank is great.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] gas tank capacity mystery [message #102788 is a reply to message #102783] Wed, 13 October 2010 09:45 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Greg,

Matt has very good advice here and here's an additional suggestion. The
lines that vent the tanks to atmosphere when you're filling are "T'd"
together down near the tanks and a single line runs up to the filler neck.
If you run TWO lines and "T" them together as close to the filler neck as
possible you will have less problems with burping when you fill your tanks.

Unfortunately I didn't hear about this until AFTER I had replaced all the
lines from the tanks!

Also make sure whatever lines you use are compatible with ethanol:

http://www.goodyearep.com/ProductListing.aspx?folderid=1036

Gates makes a "superhose" too.

Finally if the canister under the passenger's seat fills up with gas the
float in the drivers side wheel well could be shot. Call Jim B as he's found
the EXACT replacement. It's even marked with the same manufacturers name!

Regards,
Rob M.
USAussie


-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Matt Colie
Sent: Wednesday, October 13, 2010 8:11 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] gas tank capacity mystery


Greg,

<snip>

Where you smell gasoline vapor from can be an indicator of other things that
need attention. If all the rubber in the fuels system has not been replaced
recently, it probably should be.


Matt
--
Matt & Mary Colie
'73 Glacier 23 Chaumiere (say show-me-air)
SE Michigan - DTW 3.2/4R
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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] gas tank capacity mystery [message #102789 is a reply to message #102768] Wed, 13 October 2010 10:19 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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Registered: November 2004
Location: Dexter, Mo.
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Whew, you guys are daredevils, Matt and Paul. I am not checking my tanks like yall do. 30 gallons is a big fill for me. I hate getting below half on the gauge and that is about 30 gallons. Keeps my life much more enjoyable, sitting beside my lovely bride inside the coach. When yall run out of gas, tell me again how many gallons you put in. Very Happy
Great seeing both of you at Du Quoin.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] gas tank capacity mystery [message #102790 is a reply to message #102789] Wed, 13 October 2010 10:41 Go to previous messageGo to next message
kelvin is currently offline  kelvin   United States
Messages: 608
Registered: February 2004
Location: Eugene, OR
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Chicken!

370miles on the first tank (Eugene, OR to Corning, CA) took 40.6 gallons
and got 9.1mpg. This was climbing from 400ft to 5100 feet and back to
600ft or so. Pretty decent mileage considering some of the grades we
went up.

376miles on the second tank (Corning to SF and back to Redding) took
39.6 and got 9.5mpg (now THAT is decent mileage) Pretty flat freeway
travel.

346miles on the third (Redding to Eugene) and I haven't filled it yet
but I'm guessing well over 30 gallons.
Again, climbing from sea level to 5100ft and back again. I expect that
same 9mpg.

I still had 10+ gallons (80-90 miles) so why worry? I really hate the
time wasted filling the tanks. I'm going to stop as few times as possible.

Kelvin

> Whew, you guys are daredevils, Matt and Paul. I am not checking my tanks like yall do. 30 gallons is a big fill for me. I hate getting below half on the gauge and that is about 30 gallons. Keeps my life much more enjoyable, sitting beside my lovely bride inside the coach. When yall run out of gas, tell me again how many gallons you put in. :d
> Great seeing both of you at Du Quoin.
> Dan

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Re: [GMCnet] gas tank capacity mystery [message #102791 is a reply to message #102768] Wed, 13 October 2010 10:48 Go to previous messageGo to next message
Jim Galbavy is currently offline  Jim Galbavy   United States
Messages: 1443
Registered: August 2007
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Senior Member
greg,

Yes, with a stock coach we have two 25 gal. fuel tanks(approx.).
As stated by the others, you then need to take in to account the volume of ALL of the related plumbing. How far up the filler pipe did you add fuel? I once filled up in the cool of a summer morning only to have gas flowing out the filler pipe later when the temp hit above 95* in the afternoon. I think because you emptied your tanks and lines you saw the results of filling the system up from scratch.

jim galbavy
'73 X-CL ANNIE
Chesterfield, Va & Lake Mary, Fl
Re: [GMCnet] gas tank capacity mystery [message #102800 is a reply to message #102789] Wed, 13 October 2010 12:33 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
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Senior Member
WD0AFQ wrote on Wed, 13 October 2010 11:19

Whew, you guys are daredevils, Matt and Paul. I am not checking my tanks like yall do. 30 gallons is a big fill for me. I hate getting below half on the gauge and that is about 30 gallons. Keeps my life much more enjoyable, sitting beside my lovely bride inside the coach. When yall run out of gas, tell me again how many gallons you put in. Very Happy
Great seeing both of you at Du Quoin.
Dan

Dan,

It may sound like I am some kind of daredevil as far as fuel, but there are two big things you probably have not considered.

This coach has been my daily driver most of the last 4 years. That is about 10k miles inside a 100 map mile radius. Most all of that in well populated areas. I was seldom more than a mile from a gas pump. Pushing it to that limit when it is safe lets me know what I can do if I should ever be forced to run that edge.

As pilot of both water and aircraft, fuel management has been a lifelong and serious study. If you blow your fuel management when you are flying a small plane, this can end very badly (Ask Ken B). Even in ships and boats, you can up in serious trouble by having no fuel when you really need it. Ground vehicles, on the other hand, do not fall out of the sky or end up on the rocks if the motor stops.

May you never get below the half tank mark when you are in the middle of out back and beyond.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] gas tank capacity mystery [message #102803 is a reply to message #102768] Wed, 13 October 2010 12:53 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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Location: Dexter, Mo.
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Kelvin, you are driving a "wanna bee", 23 footer. LOL
So is Matt but I did not realize it was your daily driver. That is fantastic. I am guessing you use it for some kind of work. Both of your coaches are little Glaciers. Mine is a big Glacier. Takes more fuel, but this new engine will get over 9mpg not towing the Vibe. There is a reason, or two, that I don't like getting below half tank, and that is on all of my vehicles. Have never run out of gas. Thought I had, twice. Once in the Mustang and once in the GMC out at Jim K's place. Both times was owner error, was not out of fuel.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] gas tank capacity mystery [message #102814 is a reply to message #102803] Wed, 13 October 2010 14:36 Go to previous messageGo to next message
mlincoln is currently offline  mlincoln   United States
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Location: Salt Lake City
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In gliders too, but not as much because they're designed to "land out". Once I was returning from a long cross county in to S. Utah in my Grob Twin Astir (like this one: http://en.wikipedia.org/wiki/Grob_G_103_Twin_Astir). A relative cross country novice, I had in retrospect dawdled too long flying at my best glide speed during the hot afternoon. With abundant thermal fuel & easy to gain altitude, I should have been flying much faster between thermals. At sunset I was still 20 miles from the field-- poor planning in a sun-powered aircraft-- and down below 5800 feet (ca. 700 feet above the ground). I was planning to land in a wheat field when, like the big Conoco sign shining on the side of the freeway (GMC content), I saw a hawk circling a half mile away. That hawk knew something! I headed for the hawk, which had located perhaps the last thermal of the day. We flew in tight circles--he out-climbed me of course, being a natural expert--up to about 10,400 feet. I arri
ved back at the airport at sunset with altitude (i.e., fuel) to spare (38:1 glide ratio).

Mike Lincoln
1978 Coachman CK Royale TZE-368V100993
1980 Grob Twin Astir N8485W


> As pilot of both water and aircraft, fuel management has been a lifelong and serious study. If you blow your fuel management when you are flying a small plane, this can end very badly (Ask Ken B).
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Mike
Re: [GMCnet] gas tank capacity mystery [message #102833 is a reply to message #102814] Wed, 13 October 2010 16:56 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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mlincoln wrote on Wed, 13 October 2010 14:36

In gliders too, but not as much because they're designed to "land out". Once I was returning from a long cross county in to S. Utah in my Grob Twin Astir (like this one: http://en.wikipedia.org/wiki/Grob_G_103_Twin_Astir). A relative cross country novice, I had in retrospect dawdled too long flying at my best glide speed during the hot afternoon. With abundant thermal fuel & easy to gain altitude, I should have been flying much faster between thermals. At sunset I was still 20 miles from the field-- poor planning in a sun-powered aircraft-- and down below 5800 feet (ca. 700 feet above the ground). I was planning to land in a wheat field when, like the big Conoco sign shining on the side of the freeway (GMC content), I saw a hawk circling a half mile away. That hawk knew something! I headed for the hawk, which had located perhaps the last thermal of the day. We flew in tight circles--he out-climbed me of course, being a natural expert--up to about 10,400 feet. I arri
ved back at the airport at sunset with altitude (i.e., fuel) to spare (38:1 glide ratio).

Mike Lincoln
1978 Coachman CK Royale TZE-368V100993
1980 Grob Twin Astir N8485W


> As pilot of both water and aircraft, fuel management has been a lifelong and serious study. If you blow your fuel management when you are flying a small plane, this can end very badly (Ask Ken B).



Yes, It almost ended short for me only one time after dark going into an unlighted grass strip in Stephen A. Forbes State Park in Illinois. I now manage fuel by the clock. 1/2 hour switch tanks. I have two stop watches mounted in the airplane. One does one half hours and is reset for the next half hour. The other does total flight time.

I always leave with FULL tanks unless I have to go into a short strip and depart again on a hot day.

I'm a lot less cautious in my GMC because I know I always could hop on my scooter or motorcycle and go get gas. I plan my gas stops by where gas is cheap and where I can get non-alcohol fuel.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] gas tank capacity mystery [message #102836 is a reply to message #102768] Wed, 13 October 2010 17:11 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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You must have missed my posting a week or two ago after DuQuoin. I intentionally ran my coach out of gas on the main tank. I ran out of gas 1/2 mile short of the Flying J. That should have left 7 gallons in the reserve tank. I drove to Flying J on the reserve tank and filled up after lunch. It took 50.1 gallons. By my calculations the two tanks would then hold 57 gallons bone dry. The next time I get chance I'll run the reserve (aux) tank dry and and use the main for the reserve. Then we will see what the fill up amounts is. I assume it will be the same - around 50 gallons.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] gas tank capacity mystery [message #102838 is a reply to message #102836] Wed, 13 October 2010 17:19 Go to previous messageGo to next message
hal kading is currently offline  hal kading   United States
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Ken,

A much better check would be to run them both dry. Rules out any transfer back and forth between tanks on hills and starting and stopping. Laughing Keep us advised!

Hal Kading 77 Kingsley 455 Las Cruces NM



Hal Kading 1978 Buskirk Stretch 502 Las Cruces NM
Re: [GMCnet] gas tank capacity mystery [message #102840 is a reply to message #102836] Wed, 13 October 2010 17:21 Go to previous messageGo to next message
kelvin is currently offline  kelvin   United States
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Registered: February 2004
Location: Eugene, OR
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Senior Member
The first time I had the fuel tanks out I put 5 gallons in after
reinstalling them and drove 1.5 miles to a gas station to fill it up.
55.6 gallons filling it right to the brim (could see fuel in the filler
neck)

Then we headed out on a trip. I'd never fill it that full unless I was
hitting the road right away.

I've ran the main tank out of fuel a few times figuring there is at
least 5 usable gallons in there. I'm seldom more than 40 miles from a
gas station. I just like to exercise that AUX switch now and then. GM
put it there to be used. :-)

Kelvin



>
> You must have missed my posting a week or two ago after DuQuoin. I intentionally ran my coach out of gas on the main tank. I ran out of gas 1/2 mile short of the Flying J. That should have left 7 gallons in the reserve tank. I drove to Flying J on the reserve tank and filled up after lunch. It took 50.1 gallons. By my calculations the two tanks would then hold 57 gallons bone dry. The next time I get chance I'll run the reserve (aux) tank dry and and use the main for the reserve. Then we will see what the fill up amounts is. I assume it will be the same - around 50 gallons.

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Re: [GMCnet] gas tank capacity mystery [message #102841 is a reply to message #102838] Wed, 13 October 2010 17:27 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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Hal Kading wrote on Wed, 13 October 2010 17:19

Ken,

A much better check would be to run them both dry. Rules out any transfer back and forth between tanks on hills and starting and stopping. Laughing Keep us advised!

Hal Kading 77 Kingsley 455 Las Cruces NM





Yea, try what Hal said, Ken. I was in the middle of ND when that nearly happened to me. Nothing up there for miles and miles. Was trying to save a nickle when I passed the last fuel stop. I dont do that anymore. Needless to say, I was really TIGHT when I found a place to get fuel. Teri was not happy with me one bit.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] gas tank capacity mystery [message #102854 is a reply to message #102841] Wed, 13 October 2010 18:39 Go to previous messageGo to next message
jaholland is currently offline  jaholland   United States
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WD0AFQ wrote on Wed, 13 October 2010 17:27

Hal Kading wrote on Wed, 13 October 2010 17:19

Ken,

A much better check would be to run them both dry.
Rules out any transfer back and forth between tanks on hills and starting
and stopping. Laughing Keep us advised!

Hal Kading 77 Kingsley 455 Las Cruces NM





Yea, try what Hal said, Ken. I was in the middle of ND when that nearly happened
to me. Nothing up there for miles and miles. Was trying to save a nickle when
I passed the last fuel stop. I dont do that anymore. Needless to say,
I was really TIGHT when I found a place to get fuel.
Teri was not happy with me one bit.
Dan




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dan;
I know how you must have felt. LOL

Last December we filled up our '78 Eleganza II at the Walmart in Ft Smith Ar.
Feeling good and headed back to Birmingham, we decided to drive straight thru ~
On I-22, and using the C/C just east of Tupelo, The Low Fuel Warning Light Came On ~
I saw the fuel gauge was on empty so I just switched tanks ~

I Then Saw That Fuel Gauge Quickly Go From 1/2 to 1/4 And Creep To EMPTY while
we were scanning the dark countryside desperately looking for ANY GAS STATION ~

THEN

We saw the Fulton Mississippi Exit, we slowly proceded to the Walmart ~
I put In 30 Gallons Before it burped, I then slowly added 4 more gallons to the tanks ~

Back inside the MotorhomeI saw that we had driven 412 miles on that last fill-up ~
That Trusty Ole '403' Went 412 Miles @ 65 MPH on Cruise Control
using 34 Gallons ~
I said "Never Again", ~

We Usually Start Looking For A Good Fuel Stop At The 250 Mile Point ~

~ Joe ~


/_]*[__][] *[__|] ~ * '73 TZE063V101887 "
" O----------OO--]* ~ '78 TZE168V100234 "
" " Joe & Lavelle " "
" 'sweet home alebamy'

[Updated on: Wed, 13 October 2010 18:45]

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Re: [GMCnet] gas tank capacity mystery [message #102859 is a reply to message #102854] Wed, 13 October 2010 19:04 Go to previous messageGo to next message
storm'n is currently offline  storm'n   United States
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 That's 12.1 m.p.g.




> Yea, try what Hal said, Ken. I was in the middle of ND when that nearly happened to me. Nothing up there for miles and miles. Was trying to save a nickle when I passed the last fuel stop. I dont do that anymore. Needless to say, I was really TIGHT when I found a place to get fuel. Teri was not happy with me one bit.
> Dan




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dan;
I know how you must have felt. LOL

Last December we filled up our '78 Eleganza II at the Walmart in Ft Smith Ar.
Feeling good and headed back to Birmingham, we decided to drive straight thru ~
On I-22, and using the C/C just east of Tupelo, The Low Fuel Warning Light Came On ~
I saw the fuel gauge was on empty so I just switched tanks ~

I Then Saw That Fuel Gauge Quickly Go From 1/2 to 1/4 And Creep To EMPTY while
we were scanning the dark countryside desperately looking for ANY  GAS STATION ~

THEH

We saw the Fulton Mississippi Exit, we slowly proceded to the Walmart ~
I put In 30 Gallons Before it burped, I then slowly added 4 more gallons to the tanks ~

Back inside the MororhomeI saw that we had driven 412 miles on that last fill-up ~
That Trusty Ole '403' Went 412 Miles @ 65 MPH on Cruise Control
using 34 Gallons ~
I said "Never Again", ~

We Usually Start Looking For A Good Fuel Stop At The 250 Mile Point ~
~ Joe `
412 miles
--
Joe & Lavelle of ALEBAMY

Previously owned a '65 6cyl Cortez, '68 8cyl Cortez, 1973 GMC 26' Canyonlands & Now a'78 Eleganza II 26' {"The Ole Gospel Ship"} 

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Re: [GMCnet] gas tank capacity mystery [message #102867 is a reply to message #102859] Wed, 13 October 2010 19:57 Go to previous messageGo to next message
jaholland is currently offline  jaholland   United States
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storm'n wrote on Wed, 13 October 2010 19:04

 That's 12.1 m.p.g.




> Yea, try what Hal said, Ken. I was in the middle of ND when that nearly happened to me. Nothing up there for miles and miles. Was trying to save a nickle when I passed the last fuel stop. I dont do that anymore. Needless to say, I was really TIGHT when I found a place to get fuel. Teri was not happy with me one bit.
> Dan




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dan;
I know how you must have felt. LOL

Last December we filled up our '78 Eleganza II at the Walmart in Ft Smith Ar.
Feeling good and headed back to Birmingham, we decided to drive straight thru ~
On I-22, and using the C/C just east of Tupelo, The Low Fuel Warning Light Came On ~
I saw the fuel gauge was on empty so I just switched tanks ~

I Then Saw That Fuel Gauge Quickly Go From 1/2 to 1/4 And Creep To EMPTY while
we were scanning the dark countryside desperately looking for ANY  GAS STATION ~

THEH

We saw the Fulton Mississippi Exit, we slowly proceded to the Walmart ~
I put In 30 Gallons Before it burped, I then slowly added 4 more gallons to the tanks ~

Back inside the MororhomeI saw that we had driven 412 miles on that last fill-up ~
That Trusty Ole '403' Went 412 Miles @ 65 MPH on Cruise Control
using 34 Gallons ~
I said "Never Again", ~

We Usually Start Looking For A Good Fuel Stop At The 250 Mile Point ~
~ Joe `
412 miles
--
Joe & Lavelle of ALEBAMY

Previously owned a '65 6cyl Cortez, '68 8cyl Cortez, 1973 GMC 26' Canyonlands & Now a'78 Eleganza II 26' {"The Ole Gospel Ship"} 

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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

STORM'N;

~ CORRECTION ~

I Went Back To My Lil Book Of Records To Double Check And Saw My Mistake `

I put in 30 Gallons and then Slowly Added another 3 Gallons ~
We Drove 316 Miles between the Fill-ups averaging 12.6 MPG

12.6 MPG In A 1978 GMC 26'Eleganza II Motorhome Towing A Hyundai Accent Coupe
on I-40 E in the Arkansas Flat Country and on the New I-22 E in N Mississippi ~

December 10, 2009 was a calm 40 degree F day with minor traffic and No Wind.

The '403 V/8 had a Fresh Tune up /~ New Plugs / Plug Wires / New Fuel Filters /
New Air Filter / Fresh Synthetic 15w40 Oil Change / Fresh Carb Ohaul ~

The HD425 Hydramatic Tranny had Fresh Synthetic Fluid / Filter / Modulator / Guvonor Gear ~

The 3:07 Final Drive had Fresh Synthetic Final Drive Gear Oil

The Air Conditioning Was Not Used And The Cruise Control Was Set At 65 MPH ~

I would really like to say that I always got that kind of fuel mileage
BUT on 12/10/2009
The Weather, Temperature, Road,Traffic, Fresh Tune Up And The Synthetic Oils
Combined Together Attributed To The 12.6 Mpg That Day ~

~ Joe ~

It Was 12.6 MPG Instead of 12.1 MPG
{Tomorrow I'll put on my Cowboy Boots and figure this mileage again}


/_]*[__][] *[__|] ~ * '73 TZE063V101887 "
" O----------OO--]* ~ '78 TZE168V100234 "
" " Joe & Lavelle " "
" 'sweet home alebamy'

[Updated on: Wed, 13 October 2010 20:35]

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Re: [GMCnet] gas tank capacity mystery [message #102953 is a reply to message #102768] Thu, 14 October 2010 10:50 Go to previous messageGo to next message
greg is currently offline  greg   United States
Messages: 17
Registered: May 2004
Karma: 0
Junior Member
>> So is this simply a bulging tank phenomena, and i have an
>> unintended "upgrade" to 57 gallon tanks?
>> whew! that'd be the first upgrade i didn't pay for!
>
> What you have missed is the industry standard for "Refill
> Capacity". That is what is stated on all vehicle specifications.
> It allows for some amount of dead volume (what you should not
> normally be able to retrieve) and roughly 10% expansion volume.

Thanks for the info y'all....
(Sorry, i was away from the computer for a whole day and a half and
missed the progress on my own thread!)
So I figured that a bone-dry system would eat up a gallon or 2 with
all the lines, but 6 gallons?
OK, now it makes all the more sense why i ran out of gas backing down
that hill with only 6 gallons inside.
12 years of driving these rigs, and i'm STILL learning stuff!

One of the last times i TOTALLY filled my tanks was several years ago
in Mexico, and it caused a big spill at the pump....
It looked like the overflow was coming from the top of the front
tank! When i brought it in to get looked at,
the "mechanic" told me that GMCs often leak off the top, and that it
was no big deal. Just dont fill up to the brim.
Soon after this came "the accident" (drunk driver head-on while i was
parked, bending the frame, "totalling" my RV, 6 year rebuild project),
and during all that time that the rig was in storage, i was always
under the impression that i had some monster leak off the top of the
tank.
And so last week we finally checked off that particularly ominous item
on the massive "to do" list!
Nice to see there was only a pin-hole leak up top, and whatever i saw
leaking onto the pavement that day years ago was probably overflow
at the filler neck, gushed down under the coach... the Mexican "gas
station" wasn't even on flat pavement.

So now i can fill 'er up and be ready for anything!
ie) I was about 9 years old during the gas lines of the mid-70's, and
i guess that left an impression.
And now living in crazy Los Angeles, and with the world petrochemical
situation... combined with the current Carter-esque administration....
Let's just say i feel better knowing that my tanks don't leak, and
will be keeping them close to full at all times :)

>
> greg wrote on Wed, 13 October 2010 03:42
>>
>> (Well, OK, there's some gas smell when i come to a sharp stop,
>> and we were gonna check the canisters next, but i can't imagine any
>> significant loss here...)

On Oct 13, 2010, at 9:00 AM, gmclist-request@temp.gmcnet.org wrote:

> Finally if the canister under the passenger's seat fills up with gas
> the
> float in the drivers side wheel well could be shot. Call Jim B as
> he's found
> the EXACT replacement. It's even marked with the same manufacturers
> name!

That's our next job. Of course the nuts are frozen to the bolt, and
the whole bolt spins, so we're probably going to have to cut them off.
The canister is under the passenger's seat, yes. But the float is
under the driver's wheel well?

OK, Thanks again compadres!
Greg



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Re: [GMCnet] gas tank capacity mystery [message #102979 is a reply to message #102841] Thu, 14 October 2010 16:06 Go to previous messageGo to previous message
George Beckman is currently offline  George Beckman   United States
Messages: 1085
Registered: October 2008
Location: Colfax, CA
Karma: 11
Senior Member
WD0AFQ wrote on Wed, 13 October 2010 15:27

Needless to say, I was really TIGHT when I found a place to get fuel. Teri was not happy with me one bit.
Dan


Time for confession. We knew we had used at least 34 gallons. We were on our way East for Du Quoin and other visits. It burped cresting a little hill and I switched over. It did not recover like it usually does, but did recover. I drove by an offramp with a station. We had scoped cheaper gas just ahead in MSN Gas.

She died, just within sight of the NM boarder, on 40. Of course I blamed the TBI, EBL, spark. I couldn't be out of gas. Finally checked the selector valve. 12 volts but no clicky click. 15 gallons and no click to get it. Walked, got gas. Drove back and put in lots of gas. Changed the selector valve at the Van Winkles, in MO.

Ruth was a patient girl, but she does escape reading when there is even the slightest issue. She burned a few pages that day.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
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