I don't totally agree with this comment. I have filter in my tea bag and coffee filter , but small particles do pass through it although it's not always visible , but it's there. Now don't get me started on my juicer 's filter. :-)

Are you sure that all fuel filter is 100% effective and will trap "all "particles? If so , then please tell me which brand , so I will buy it.

The filter Benz uses is 1 micron nominal, 3 micron absolute, 75 beta ratio. It is not a tea bag or a coffee bag. It is a controlled media filter.

Anything that gets through will also pass through an injector without an issue. It is so specified. If this were not so you would have many vehicles with damaged injection systems. Ever seen them cleaning a service station fuel tanks. You would be horrified.

So GLyn, are you saying that making a habit on running on a near empty gas tank is ok because the fuel filter will trap all particles and there is nothing to fear and the trade off in performance is worth it ?

I'm saying that running the tank down to reserve fuel level before refueling is fine. Read my post.

What does running on a near empty gas tank have to do with fuel filter performance?

And I'm saying to frequently running the tank down to reserve fuel or near empty level before refueling is a not a good idea. Read my original post

Definitely a case of reduced weight effect when fuel tank is near empty, thought that reason would be obvious to anyone

I've known a lot of people who also remove the spare wheel from their car/s to further reduce weight and gain a slight performance bump in the process.

And read Glyn's post. He is correct.

In most cars, isn't the fuel picked up from the bottom of the tank, in which case if you have crud at the bottom of the tank, it'll get picked up regardless how much fuel you have in the tank?

I agree with your assessment Pete, but what I'm trying to say is that the crud at the bottom of your tank will likely to be sucked up more as the fuel level decreases in the tank. Common sense will say having a full tank will have less chance of crud getting sucked up in your fuel systems.

Tony ~ your post was ill considered "noise" padded with spurious logic.

Spurious logic?, is that the only respond you can come up with? My position still stands that running on near empty tank is not a good idea and not worth it .

Until you can show me a fuel filter that will trap 100% of particles to prevent it from getting into the fuel injection system, then you really don't have any argument.

I'm done with this thread unless you have anything worth debating.

One further snippet.To prevent dirt some ingress I carry a clean rag in my boot to wipe the bowser nozzle before entering it into my car .The rag does not stay clean for very long on a diesel nozzle in fact it is putrid after half a dozen fills.

This is the stuff that drives me nuts on this forum. You posted some thoughts you had, without any facts to back them up, even trying to compare a tea bag to a media filter. Glyn used actual logic combined with factual information to show that your reasoning wasn't valid. Instead of looking at what he wrote and taking in the information, you insist that you are right - because you said so.

It makes perfect sense - fuel pump sucks fuel from bottom of tank where particles settle anyway when the car sits overnight. Driving the car causes the fuel to slosh around and mix all of this up anyway. The filter captures all of these particles and will become clogged at the end of its useful life either way, because as has been stated, it's always getting mixed into the fuel from driving. Over the life of the car / fuel filter, whatever junk gets into the tank is going to be mixed up and make its way to the filter whether you always keep it full, or you always let it run down to the low fuel light. If you want to push the issue that's fine, but only do it if you can come back with facts and evidence to the contrary that actually applies to the discussion.

Indeed ~ spurious logic.

If you understood anything about filtration you would understand that a 1 micron nominal, 3 micron absolute filter can never pass a particle larger than 3 micron which the injection system can tolerate. It is the size of particle that matters. Then we have the multipass situation with fuel returned to tank. In multipass a filter is even more effective than single pass. More likely to catch that small particle a second or third time round.

As the filter media blinds with particles larger than 3 micron so the filter becomes more effective and will become 2 micron absolute over time, as an example, until the pressure drop across the media becomes so high that you lose fuel pressure & the vehicle won't run. Obviously you should have changed the filter before this occurs.

Suggest you attend a Donaldson, Pall, Hengst or Mann + Hummel filtration course. Forget about the teabags.

Wise advice JC especially for diesel where modern 2000 bar+ amplifier injectors & pumps are less tolerant of dirt than their gasoline equivalent.

On all mining sites & similar that we supply we fit nozzle cleaners to the installations for this very reason.

No offense, but from a person that brought up a tea bag into this conversation, this sounds hilarious.

Is there some evidence out there that you can point us to that shows car engines dying as a result of dirt getting past the fuel filter due to running low on fuel?

In the distant past some vehicle makers had the foresight to add drain plugs at the bottom of their fuel tanks to purge water & excess solid contaminants .

All fuel tanks in marine , industry & agriculture have drain valves.

Your first shot at US political humor!!

Perhaps my poor attempt at sarcasm by using the tea bag example was a bad analogy. Anyhow , let's cut to the chase and see what the con-census is of where you stand. It's a simple question.

Is it a good idea to make a habit and frequently let your gas tank run to near empty? Yes or No


If you answer yes because of financial issue then , it's understandable.

Cast your vote . If anyone can make a poll for this , then that would be nice.

Financial issue? Again i'm lost in your logic here. It costs exactly the same to run a car full as it does to run it at near empty.

Anyway, my vote is that it doesn't matter.

Let me give you some good oil company research. Gasoline is a grudge purchase. The vast majority of vehicle owners only fill their car when necessary. i.e. they always run the tank from full to fuel light on. This sometimes even influences vehicle purchase where people select vehicles with larger tanks & greater range.

Cars are designed to operate endlessly in this fashion. Some of the highest miler Benzes in the world are in taxi fleets. They run from full to almost empty cycles & never have injection system problems.

You are right, but some people do live pay check to pay check and it's not a knock on them for waiting till pay day to fill up .

The choice was yes or no, but I can respect your stand on this issue. Again perhaps a poll with various choices /options besides a yes or no option will give a clearer picture.

Glyn,

You are still avoiding my simple question which was yes or no to the question of "is it a good idea" to run on a near empty gas tank frequently.

Just to let you know where I stand, I do think that MB fuel filter do a decent job , but I don't think it's advantageous to keep your gas tank near empty for perceived performance gain advantage which the original poster (John) has experienced.

This was your post & it is nonsense on multiple counts.

My answer is it makes no difference. To each his own.