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#98099 11/14/2006 3:43 AM | Joined: Oct 2006 Posts: 120 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2006 Posts: 120 | What should the voltage read at the fuel sending unit. I got 5 volts when I thought it should be the same as the battery v. Is there supposed to be resistance somewhere in the circut?
trial and error all over again. | | |
#98100 11/14/2006 5:45 AM | Joined: Mar 2005 Posts: 1,029 Member | | Member Joined: Mar 2005 Posts: 1,029 | The sending unit itself is nothing but a variable resistor . The meter movement also has resistance. There is ground on the other side of the sending unit and twelve volts on the other side of the gauge, so you effectively have a voltage divider. The voltage will change with the fuel level. The voltage on the sending unit side of the gauge will be twelve volts if you disconnect the sending unit wire. | | |
#98101 11/14/2006 3:10 PM | Joined: Oct 2006 Posts: 120 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2006 Posts: 120 | Thank you Baldy,
That is a good thing to know. Does that mean that if the voltage changes with the amt. of gas in the tank that the sending unit is working? | | |
#98102 11/14/2006 4:55 PM | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | Your gauge measures resistance. Your sending unit provides that resistance. Full position is 30 ohms resistance, empty is about 1-2 ohms. That is what you need to check. Measuring voltage will not tell you much.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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#98103 11/14/2006 7:33 PM | Joined: Jun 2006 Posts: 687 Shop Shark | | Shop Shark Joined: Jun 2006 Posts: 687 | Thats nice and all but could some body tell me why the gas dosn't exploded with an electrical devise like a sending unit or fuel pump is put in the tank. Can you spell boom? I have never seen or heard of one exploding.
I didn't do it, no one saw me do it, you can't prove anything! "Bart Simpson"
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#98104 11/14/2006 7:57 PM | Joined: Jul 2005 Posts: 1,158 Shop Shark | | Shop Shark Joined: Jul 2005 Posts: 1,158 | No spark, no boom. Plus, gasoline by itself isn't explosive, just the vapor. Of course, light it on fire and you'll see it evaporate quickly enough to cause problems.  | | |
#98105 11/14/2006 8:24 PM | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | Brendan is right plus I've read that the ratio of oxygen to fuel capable of producing an explosion is pretty precise. Too much fuel for the available oxygen and it won't burn. I watched a show on TLC a while back where they were trying to set spewing natural gas on fire using flare guns. They had to hit just the right spot or the burning flare would go right through the spouting fuel and not light it off. There would be a ton of vapor in the gas tank but little oxygen.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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#98106 11/14/2006 9:24 PM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Toyvo If your gas tank blew up it would be a terrible accident !  Stuart | | |
#98107 11/14/2006 9:36 PM | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | But in the movies a bullet can explode a gas tank. And somehow or another those little car gas tanks always have 100 gallons of gasoline in them when they explode.  | | |
#98108 11/14/2006 10:05 PM | Joined: Oct 2006 Posts: 120 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2006 Posts: 120 | Stuart It certainly would and much worse if you have a cab mounted tank -- like mine. | | |
#98109 11/14/2006 10:10 PM | Joined: Oct 2006 Posts: 120 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2006 Posts: 120 | Originally posted by redtruck65MA: Stuart
It certainly would and much worse if you have a cab mounted tank -- like mine. That reminds me. I get a strong smell of gas every time I get in the truck. The tank and filler hose are good-- no leaks so where does it come from? | | |
#98110 11/15/2006 1:11 AM | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | Probably the sending unit gasket.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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#98111 11/15/2006 11:58 PM | Joined: Oct 2006 Posts: 120 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2006 Posts: 120 | I'm retired every day -- many times a day. It's good to have the time to appreciate life and rest when you have to. | | |
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