Fuel tank size??

[dennis46c]

I have a 2008 HR Endeavor 40' SKQ with a 400hp Cummins that by all accounts has a 100 gallon fuel tank. I'm beginning to wonder. I monitor the fuel usage on the dash display and I look to refill when it indicates I've used around 40-50 gallons. I'm a little conservative and the fuel guage shows I'm near empty at that point. If it indicates I've used around 45 gallons, I can usually fill it to the top of the fill pipe with around 45 gallons. The gas guage goes up to F but it always appeared there was more room to go. I always figured the fuel gauge was way off. This weekend, it said I used around 48 gallons (I only have used the generator to excercise it) when I got a low fuel warning. I pulled into a nearby truck stop and put in 58 gallons (10 more than it said I used) and again, it went to the top of the fill pipe. This makes me wonder if I may only have a 60 gallon tank or what is happening. Any ideas? I almost always fill from the road side and there isn't any evidence of a leak in the tank. I do plan on getting underneath to measure the tank but since I believe the mfg date was well before the bankruptcy, I can't believe they would have installed a smaller tank. ANY IDEAS?

[RVRon]

I'm sure it's a 100 gallon tank. The sending units aren't completely accurate and most tend to err on the side of caution (If it HAS to be inaccurate, I'd prefer the cautious error).

[ArmyEOD]

Yes, I am also sure you have a 100 gal tank. I have seen post on how to adjust the sending unit, but I can not find one right now. On the other hand leave it like it is, It want hurt so much when you fill up. I am sure someone will post on the adjustment.

[Barlow46]

Here are all the specs on your coach. Do a search on the sending unit, there is quite a bit of info available.

http://www.holidayrambler.com/Static...08endeavor.pdf

[deSanford]

Just a thought you might want to run two new wires directly from the fuel gauge to the fuel sending unit. Sometimes the ground is not the best and may give false readings.

[danes-on-tour]

The fuel gauge installed by Monaco more than often is highly unreliable which I am sure most people will agree to.

Our will indicate empty. Then we carry on for another 100 miles and then we find that we still have about 15 galons left in the tank.

After having read how many have tried to re-calibrate the gauges we came to the conclusion that it was better for us to find out what we had left when f.x. the fuel light comes on and when the needle points at empty, rather than insisting on that "showing empty actually means empty" - if you know what I mean.

[RJay]

Hi Dennis,
According to the specifications for that year, make and model you have a 100 gallon tank. However, I found this small print at the bottom of the spec.

All tank capacities are estimated based upon calculations provided by the tank manufacturers and represent approximate capacities. The actual “usable capacity” may be greater or less than the estimated capacities based upon fabrication and installation of the tanks.

[H. Miller]

Ours has 25-30 gallons remaining when the "light" comes on. The needle has been below 1/4 tank for 100 miles.
Miles traveled divided by 8 (mpg) will give me gallons used +/- 1/2 gallon. Flown airmachines far to long to start trusting gas guages now...
BTW, the Monaco brochure says 100 gallons with no option for more or less.

[Robi.1014]

My input is that you gauge is about as accurate as it need be. Read on....

RJay is on to something when he quotes: All tank capacities are estimated...
Our tanks are 100 gallon alright, but the fill-tube "injects" into said tanks at such a position that you can only place about 80 gallons (85 maybe) in them.

Consider:
When opening your car's gas cap, you hear air escape with a whoosh. You don't hear that whoosh on our diesel tanks because they are vented to the atmosphere. That's just a factoid. The positioning of the fill-tube is by design......a design to prevent us from filling the tank so full that raw fuel might slosh onto the ground. The air-vent is on the top of our tanks and you can see the overflow tube hanging down close by (visible when you stoop down to take a look). Heat expansion of liquid fuel can't be ignored either.

Behind all this "design" is a federal regulation (or at least there is an urban legend that such a federal regulation exists).

[dennis46c]

Thanks everyone for your input! I guess the small monitor on the dash that indicates the fuel used and MPG and also gave me the low fuel warning, uses information from the sending unit that also controls needle on the fuel gauge. The sending unit decided the tank was nearly empty, as the needle indicated on the fuel guage, and sent the low fuel warning to the monitor. I always felt I had a lot of fuel left when the gauge neared empty and based on some of the responses that is the best way to look at it. I will probably leave it as is knowing if I do get low enough to get the warning light, I will not panic but begin looking to refuel. THANKS AGAIN FOR ALL OF THE REPLIES, this is a great forum becasue of the members!

[rpasetto]

Originally Posted by dennis46c

Thanks everyone for your input! I guess the small monitor on the dash that indicates the fuel used and MPG and also gave me the low fuel warning, uses information from the sending unit that also controls needle on the fuel gauge. The sending unit decided the tank was nearly empty, as the needle indicated on the fuel guage, and sent the low fuel warning to the monitor. I always felt I had a lot of fuel left when the gauge neared empty and based on some of the responses that is the best way to look at it. I will probably leave it as is knowing if I do get low enough to get the warning light, I will not panic but begin looking to refuel. THANKS AGAIN FOR ALL OF THE REPLIES, this is a great forum becasue of the members!

Monaco used Centroid sending units in a lot of their coaches... perhaps in yours. See this thread from 2009, for more info on Centroid sending units....
http://www.irv2.com/forums/f115/cent...uge-55740.html

[SteveSkinner]

A suggestion to how much fuel is left

Make up a dowel rod as a dip stick
You can temporarily mark the stick then add 10 gal of fuel
You can then safely calibrate the stick counting down from the full position.
Boats, planes, automobiles makes bi difference - all the same
I fly a Mooney TLS and always use 20 gal per hr fuel burn.
Having confirmed I use 7.4 mpg in the motor home I can easily work out remaining fuel. The calibrated dowel should show near enough just how many lots of 10 gals you have

[danes-on-tour]

Originally Posted by SteveSkinner

Having confirmed I use 7.4 mpg in the motor home I can easily work out remaining fuel. The calibrated dowel should show near enough just how many lots of 10 gals you have

I assume that 7,4 mpg is an average figure??

Personally we have had consumptions of anything from just under 6 mpg up till 10 mpg and this will make a big difference in when you would need to start looking for a gas station. Strong wind dead on the nose is "a killer" when it comes to achieving a nice mpg figure.

[RustyTools]

From all the time I've spent working/driving/fixing them, all of our series coaches have a 100 gallon +/- tank. As others have pointed-out, you may get a bit more or less each time you fill, based on lean of the coach, how fast it fills, etc, but they all came with 100 gallons. .... Unless a worker left their jacket in the tank when they made it (just kidding).

Although it hurts to say-so for what we pay for these vehicles and their toys, I'm with those who don't trust the id10t gauges (especially when flying or boating. It's embarrassing to have to call Sea-Tow 2 miles from harbor, or explain to the Highway Patrol why your little airplane is blocking an Interstate.)

I've always recorded mileage, and know best/worst/average fuel burns for various conditions. I usually plan on fuel-stops based on worst, and am happily surprised when I find it was better than that. Kind of a happy mind-game too, when I learn I didn't have to buy as much expensive fuel that time when I was expecting it.