Jump to content

Does it hurt to run low on gas?


Tulo

Recommended Posts

My dad always gives me shit for letting the gas run low in our van. He says there are sediments that settle at the bottom of the tank and they well get sucked into the engine if I let it run too low. Seems to me that driving alone would mix up anything in the tank to make the gas homogenous. Besides, isn't there a filter?? Who's right?
Link to comment
Share on other sites

There is a bit to the statements about the dirt in the tank will have more places to be besides in the pump filter, because if there is more fuel then the fuel will keep it off the floor of the tank.

 

Now that being said, there is a WAY better reason, if the vehicle is fuel injected. The pump is in the tank. These pumps are fairly reliable, but do run hot. The fuel being over the pump in the tank will nake the pmup last longer because the fuel will take the heat away from the punp.

Link to comment
Share on other sites

Guest Spyder550
The outlet for the fuel has to be at the bottom of the tank anyway, or else you would stop being able to use gas before the tank got empty. You'd run out at 1/8, 1/4 - something like that. So, no matter how full the tank is, the sediment will settle right on top of, or near to, the outlet.
Link to comment
Share on other sites

Originally posted by Kevin R.:

Yes, it makes the fuel pump work harder.

 

That would be the only reason.

No, that's not the reason at all.

 

The fuel pump is nothing more than an electric motor that spins at a constant rate (based on amount of voltage to it). Technically, it wouldn't work as hard with no fuel, as it would have nothing to push.

 

The fuel cools the unit. Some cars, like my Formula, have the fuel pump inside a casing; this case is fed constant fuel by the fuel system return line. This helps ensure the fuel pump has fuel around it constantly. Even then, it's not a great idea to run it low on fuel.

 

Also, a fuel pump will never get the tank bone dry, even when you run out of gas. You really won't pick up sediments; most likely will pick up more water than anything else running it until it runs out of gas.

 

Overall, normally the worst things that happen are damaged filters and burned up fuel pumps.

Link to comment
Share on other sites

I have only heard one thing that relates to this at all. and that is that if there is little gas covering the pump, then your pump can rust and stop working. i dont know if i believe this or not though because the guy i heard it from was really old and didnt seem all there to me, just what i heard though
Link to comment
Share on other sites

What nitrousbird said. most newer (all?) cars have the fuel pump sitting down inside a chamber within the tank. The reasoning behind this is to keep fuel at the pump through curves and hard acceleration when the tank isnt completely full. The return line is routed back into this chamber, keeping fuel at the pump at all times.

 

The ONLY consequence of running the tank almost empty all the time is that b/c the pump relies on fuel to cool itself, it runs hotter - shortening its life span.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...