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Topic: My Dash Fuel Gauge No Longer Reliable (If it works at all) (Read 967 times) previous topic - next topic

My Dash Fuel Gauge No Longer Reliable (If it works at all)

So I use my VMS-240C.
 
Right now my VMS tells me I've used 111 gal out of my full tank of 194 gal.  I've not used any fuel for the generator this fill up. My experience is the VMS is reasonably accurate (that is, if I filled up now I would put in 110 gal plus or minus 5 gal).
 
The next (reliable diesel) Flying J is 30 gal away. 111 + 30 = 141, which leaves 53 gal theoretically.  Would you go for the Flying J without a worry?
___

best, paul
"Thriving not surviving" <(*¿*)>
Paul Schaye (at 2008 NYC Marathon)
See our blog at LazyDazers.com
1999 U320 40' 1200 watts on roof. 12cf AC/DC Cold plate fridge/freezer. VMS 240 CL Honda Element

Re: My Dash Fuel Gauge No Longer Reliable (If it works at all)

Reply #1 –
Paul, My coach has had three senders and none of them have worked for long.  I  know that I get 8 MPG and have 140 Gallon tank so I run 800 miles and then look fort fuel. The gauge never shows more than 1/2 a tank and then it will start to show correctly below 1/2. So far my system has worked.

Re: My Dash Fuel Gauge No Longer Reliable (If it works at all)

Reply #2 –
Quote
The next (reliable diesel) Flying J is 30 gal away. 111 + 30 = 141, which leaves 53 gal theoretically.  Would you go for the Flying J without a worry?

YES,
But I would also look at how many miles I did with that 111 gls .
For instance if I get 7 mpg , I should have gone 777 miles.
Then I would say the gallons used was accurate enough.
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: My Dash Fuel Gauge No Longer Reliable (If it works at all)

Reply #3 –
FWIW....Understanding that I have run out of fuel 3 times.......you should be fine with just a smidgen over a quarter of a tank....call me if you don't and I will tell you the easy way to get fuel back into the system... :D :D :P
We are only strangers until we meet; however, some of us are stranger than others

Re: My Dash Fuel Gauge No Longer Reliable (If it works at all)

Reply #4 –
 
Quote
Quote

 The next (reliable diesel) Flying J is 30 gal away. 111 + 30 = 141, which leaves 53 gal theoretically.  Would you go for the Flying J without a worry?

YES, But I would also look at how many miles I did with that 111 gls . For instance if I get 7 mpg , I should have gone 777 miles. Then I would say the gallons used was accurate.

Right. I used past mpg to come up with the 30gal (plus, the 30 gal includes an additional 3 gal more than the actual calculation for conservatism)
___

best, paul
"Thriving not surviving" <(*¿*)>
Paul Schaye (at 2008 NYC Marathon)
See our blog at LazyDazers.com
1999 U320 40' 1200 watts on roof. 12cf AC/DC Cold plate fridge/freezer. VMS 240 CL Honda Element

Re: My Dash Fuel Gauge No Longer Reliable (If it works at all)

Reply #5 –
Remember, particularly when it is HOT out, you don't want to run low on fuel.

For every gallon of fuel that goes to the engine, only a few ounces are burned.  The rest is used to lubricate and cool the head and injectors.  A fuel tank near empty will raise fuel temperatures.

In fact I put a fuel cooler (similar to transmission cooler) on the fuel return line.  Leave it exposed in the summer, covered in the winter.

Brett Wolfe
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: My Dash Fuel Gauge No Longer Reliable (If it works at all)

Reply #6 –
Wow! Thats a revelation. Does the Cumins also use fuel for cooling? Could that have had a bearing on my past heating problems? I think I have it resolved with my Aux Radiator in the front, but I sure didn't know the fuel also cooled the engine.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: My Dash Fuel Gauge No Longer Reliable (If it works at all)

Reply #7 –
The gas guage on my 1996 U320 was unreliable and eratic (showed 1/4 tank after fillup and needle moved up/down by 3/4 tank each hour) when I purchased it in April at MOT.
I drove to California using a nut on a string to dip the tank.

I labelled the three wires connected to the sending unit on top of the tank, then disconnected them and cleaned the sender contacts and the wire terminators using fine sandpaper.
Fuel guage become much more reliable and has remained so. It is not as accurate as the fuel gauges in automobiles and shows erratic behaviour of perhaps 1/8th tank (useable).

I also removed the sending unit and determined that it is two concentric conducting tubes in the main tank, on the passenger side of the tank. There are no baffles around the tubes. Fuel level is estimated by measuring the resitance between these tubes. The resistance between these tubes is affected by how much of these tubes is wet with diesel. The fuel guage will be most accurate when parked on level ground, but will be somewhat eratic when driving due to the fuel slooshing around inside the tank.

Wyatt
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada
 

Re: My Dash Fuel Gauge No Longer Reliable (If it works at all)

Reply #8 –
Again, I agree with Wolfe, I also use a 4 row aux transmission cooler on the return fuel line, this is one of many trix used with stationary engines.
Learned this with Cat and used it on DDA and Cummins. lower fuel temp gives better power and mileage too, lower temp of fuel tank a lot, sure  not needed in the warm seasons.
I simply remove the cooler in the winter, reinstall in warm wx.
As for the VMSpc, I trust it 99%. From demonstrated experience.
FWIW
Dave