Community Forums

montiem · 05-29-2010, 09:26 AM

It seems that when I get one thing fixed anther thing pops up, my coach has an Aladdin Fuel system computer. It seems that every time I fill up the amount I used will be much more than the computer states that was used. For example I about 200 miles, I put in the tank 3 less gallons than the computer says I used at a fuel mileage of 8.3 but by my calculations it was 7.0. Is there a way to correct or adjust the computer
Montie

PizzaGuy · 05-29-2010, 05:44 PM

Hi Montie. I am not 100% confident in this reply, but I think that the Aladdin only measures fuel usage for the engine. It does not measure your generator usage. So, If you use your generator at all, this may be a cause for the discrepancy. When I first got my Dip I paid close attention to my mileage. Now I don't even look. It hurts too bad. But because of your post I just looked at mine for a 486 mile trip. 7.1. Now I will be in a bad mood all day. I'll get over it in just a few minutes. I love my coach.

Good Luck

Pusherpilot · 05-29-2010, 06:16 PM

I've had it go both ways, sometimes I can get more in the tank than the aladdin shows as used and others I miss it by a couple of gallons. The problem is which way the coach is leaning and which side i fill from when refuleing. Our tank is 125 gal but there is a headspace that, in most cases never gets filled. I suspect that if the tank has 100-110 gal in it after filling I'm doing good. I also don't run the fuel close to out because if I get on a road with a high crown I might have 10 gal or so but the pickup, which I think is in the center of the tank, could be sucking air. I once ran out of fuel about 50ft from the fule island and put 5 gal in it to get me there. In all I was able to put only 105 gal in it.

I use the aladdin consumption numbers to plan stops and tell me what the mpg is. Don't get excited if you can't make everything jibe, the computer is right.
Ron

montiem · 05-29-2010, 07:06 PM

I understand the poor mileage by my calculations I got 7.4 but by the computer I 8.3, I did not run the generator at all. I just thought there may be a way to adjust the flow meter

montiem · 05-29-2010, 07:09 PM

I hope your right about the computer being right, the mileage and the time is correct but I think the flow is off, if not I am averaging over 8 MPG which is great.

montiem · 05-29-2010, 07:11 PM

I have a car with a computer, when I fill up it is usually real close to amount used, but it only hold 18 gallons.

itdave · 05-30-2010, 05:52 AM

I find it impossible to do a manual calculation of MPG, since doing that requires I fill the tank to the same level each time. I can tell from my fuel gauge, that even though I can't get any more fuel in the tank, it give a different full read from one stop to the next. How much fuel I get in the tank is based on the slant of the pad at the fuel island and which side I fuel from. A difference of 3 to 5 gallons in a 100 gallon tank does not some like much of an error in filling. Calculating mileage over only 200 miles does not make much sense, I would think 2 or 3 tanks would give a more accurate average.

ddoc1 · 05-30-2010, 09:57 AM

Can anyone tell me if fuel used from the generator running is indecated on the Aladdin Fuel System?

Denali · 05-30-2010, 11:27 AM

Quote:

Originally Posted by ddoc1

Can anyone tell me if fuel used from the generator running is indecated on the Aladdin Fuel System?

No, the Aladdin system gets that information from the engine ECM. It doesn't know anything about fuel consumed by the generator (or Aqua-Hot, if you have one).

That becomes real obvious when we boondock for extended periods. We'll run the tank down to less than a quarter full with the genset and Hydro-Hot, and the Aladdin system thinks the tank is still full.

Pusherpilot · 05-30-2010, 11:32 AM

Quote:

Originally Posted by ddoc1

Can anyone tell me if fuel used from the generator running is indecated on the Aladdin Fuel System?

On ours the fuel used by the genny and the AquaHot do not register as usage. I estimate the usage by how many hours they have run calculating 1/2 gal for each hour per unit. We use the genny so infrequently that it's not a factor but if I were boondocking and using it regularly I'd do the math. I did that with the AH last year at the winter stop and was about 5 gals off on the refill but since it's impossible to be really accurate I'm happy with that. The genny will quit at 1/4 tank because the pickups won't go any lower but as I understand it, the AH could run us dry if we let it.
Ron

Denali · 05-30-2010, 02:43 PM

Quote:

Originally Posted by Pusherpilot

On ours the fuel used by the genny and the AquaHot do not register as usage. I estimate the usage by how many hours they have run calculating 1/2 gal for each hour per unit. We use the genny so infrequently that it's not a factor but if I were boondocking and using it regularly I'd do the math. I did that with the AH last year at the winter stop and was about 5 gals off on the refill but since it's impossible to be really accurate I'm happy with that. The genny will quit at 1/4 tank because the pickups won't go any lower but as I understand it, the AH could run us dry if we let it.
Ron

All Aqua-Hot/Hydro-Hot units use the same 0.35 gallon/hour fuel nozzle. You can use the hour meter on your Aqua-Hot to determine how much fuel it is consuming while boondocking.

Last winter in Quartzsite, I carefully tracked our generator (Onan 7500 QD) and Hydro-Hot usage, and I calculated that over a period of three months the generator was using 0.33 gallons/hour.

Although I have nothing more than the reports of others to verify this, at least on Monaco-built rigs the Aqua-Hot fuel pickup is at the same level as the generator pickup in the tank. That would be specific to the coach builder, I suppose.

nodine · 05-31-2010, 02:42 AM

Quote:

Originally Posted by montiem

I understand the poor mileage by my calculations I got 7.4 but by the computer I 8.3, I did not run the generator at all. I just thought there may be a way to adjust the flow meter

My advice is to not take fuel mileage to serious. The only way to get good fuel mileage on one of these beasts is to always go down hill. It is what it is and you will enjoy things more if you just except your average fuel mileage is 7 MPG and use that figure to calculate trip cost. As for the 8.3 MPG, that is most likely accurate for the distance traveled and the fuel required by the engine to get you there. The ECM calculates fuel consumption based on the pulse width and frequency of injector firings. If all the injectors are working properly the fuel consumption estimated in that manner should be more accurate than you could ever get by filling the tank and using the pump gallons.

Bob

montiem · 06-07-2010, 06:03 AM

Thanks Bob, that is what I have decided, if you want to play you have to pay the price. I have the computer on board and really just wanted to know if it was doing the job, if not I want to make the adjustment. See you on the road.