Gas tanks and fuel economy

[jessef]

Hi, Jessie,
pls dont do that it might cause you more money to fix more thing to get wrong just to prove the real amount of fuel & the fuel consumption of this delica.
you dont want to spend more than 1,000 just to find the real calculation for this delica.as it might clug the injection pump & injector.
as i did send before roughtly my calculation as i drive i drive a delica in everyday used for 4 1/2 yrs now in canada, from going to seattle back & city driving,
the most common fuel mileage you can get is min. 8.5 -11.5 Kms Max per liter, depends on the condition , tuning or way of driving your delica. can not go further than that.
so i hope you can realized this, not i dont like you to do this as it might cost you problem & money to fix your delica.
its just a advise. as its not cheap & easy to fix
hope this help;
Cheers;

Hey Mardy,

I'll take your advice and not go through with it.

I am going to have the tank cleaned/lined though. I got that recommendation from the guy's at peterbuilt who work on diesel's 24/7.

Jesse

[mararmeisto]

...I have noticed that the fuel gauge is somewhat creative in it's interpretation of capacity... does anyone here know how (or even if) I should correct for this?...

From another of my posts:

Another point to the accuracy of the needle meter: a resistively deflected needle, such as the fuel gauge or the temperature gauge, is most accurate only at mid-scale deflection. This is not to say that the reading is completely out-to-lunch at the ends, it just means that whatever inaccuracies exist are usually exaggerated at the extremes.

Also, for the other question regarding the two tanks: the two tanks are daisy-chained together and the fuel goes into the rear tank (from the filler), through the forward tank to the fuel system. When the gas-pump-light comes on, there is supposed to be 7 litres of fuel remaining, which means you should be able to go another 50km (which I think is some sort of industry standard).

[Johnny&Ruby]

Thanks marameisto!

[The Pinkfingers]

Yeah, thanks everyone. Very informative.

[Adam]

pls dont do that it might cause you more money to fix more thing to get wrong just to prove the real amount of fuel & the fuel consumption of this delica. you dont want to spend more than 1,000 just to find the real calculation for this delica.as it might clug the injection pump & injector. so i hope you can realized this, not i dont like you to do this as it might cost you problem & money to fix your delica.
its just a advise. as its not cheap & easy to fix

OK, this is a fear that I just don't understand. Why would running your diesel tank dry cost a $1000 in repairs? Are you worried about debris at the bottom of the tank getting sucked up with the last of the fuel? Isn't the fuel pickup located at the bottom of the tank anyway? Even if there was some debris that was picked up wouldn't the fuel filter block it before it hits you injector pump?

I'm running on veg oil and I've run that tank dry more than once without any problems? Please let me know what the dangers of running your diesel tank dry are and why.

[MardyDelica]

Hi, as you know, you think fuel filter will all get all the small particle Dibres & water. i dont think fuel filter can do all the work. the reason i say that i might cost you about 1000 of repair or more is that, if you got a water or other small particle came from your dirty tank that by pass the fuel filter. would it be to late for you to think that it, it might damage your fuel pump & injector as you cannot just see this.
this is just a precaution to everyone not recommend to do this.
as i did see some of this pump accur this type of problem when they do that.
just ask any local diesel truck mechanic says if thats true.1000 damage cost of repair is just estimate maybe more if you do this.
its your choice. remember the pump assy is expensive.
would anybody risk, i dont think so, we are talking about diesel with injection pump, not like gas even your run out of fuel, its o.k. butthe result it could plug your gas injector for gas engine.
this is just advice adam, that it will potencially expensive to fix, anyway nobody want to dry out of fuel when your driving this vehicle to prove the exact fuel economy. i dont thik its a wise idea.
just athough adam
cheers;

[jessef]

I think I should clarify what I did on my Pajero and what I will do on the Delica.

1. Take the tank out and have the shop clean / line it.

2. Clean fuel lines or replace if necessary.

3. Replace filters.

4. Fill to brim with diesel.

5. Drive till empty. Log km's. Prime/air out. Drive.

This way I run clean diesel from a clean tank.

Jesse

[Adam]

Hi, as you know, you think fuel filter will all get all the small particle Dibres & water. i dont think fuel filter can do all the work. the reason i say that i might cost you about 1000 of repair or more is that, if you got a water or other small particle came from your dirty tank that by pass the fuel filter. would it be to late for you to think that it, it might damage your fuel pump & injector as you cannot just see this.
this is just a precaution to everyone not recommend to do this.
as i did see some of this pump accur this type of problem when they do that.
just ask any local diesel truck mechanic says if thats true.1000 damage cost of repair is just estimate maybe more if you do this.
its your choice. remember the pump assy is expensive.
would anybody risk, i dont think so, we are talking about diesel with injection pump, not like gas even your run out of fuel, its o.k. butthe result it could plug your gas injector for gas engine.
this is just advice adam, that it will potencially expensive to fix, anyway nobody want to dry out of fuel when your driving this vehicle to prove the exact fuel economy. i dont thik its a wise idea.
just athough adam
cheers;

What I am having a hard time understanding is where is this water and debris accumulating? Perhaps you could answer a couple of questions for me so that I can get this clear in my own mind:

1) Where is the fuel pickup located in the tank? I suspect that it draws fuel from the bottom of the tank, but I've never looked inside my tanks to confirm.

2) Where would water and debris accumulate in the tanks? At the top, or bottom?

3) Wouldn't normal driving be enough to prevent much accumulation of water/debris in any one area? I know my veg oil tank sloshes around quite a bit when I hit railroad tracks or take a tight corner.

4) Why would the fuel filter not stop debris larger than 10 microns from entering the injector pump? Would it not just get plugged and starve the engine of fuel if large amounts of debris were sucked up?

I'mm not trying to be combative, I know this issue has been debated a few times before on the forum, I'm just trying to understand the logic of why this would be bad. Saying "better safe than sorry" doesn't really cut it for me.

BTW, I agree that it is not necessary to run the tank dry to determine fuel economy, all you need to do is fill up, drive for a few hundred km, fill up again and see how much fuel you used for how far you went.

[MardyDelica]

Hi, adam, there is always a condensation of water inside the tank when its cold, even when its 1/2 tank. you can build up water in there in your tank same as with gas engine.
as per you are saying how could the small dirt or particle go inside the pump while there is a filter,
i would say i dont know, i just share this experience as thru my knowledge as this is bad to have yellow light come on.
we are not debating on this adam. as you stated. this is my opinion as
nobody want to have this problem. as i deal with diesel engine for long time. hope this clarify you. its just exchaging info & opinion.
again you can clarrify this to any heavy duty diesel mechanic who know about diesel engine.
cheers;

[Adam]

Alright, unless someone can give me a decent reason not to I'm running mine dry. I've got about 40L of diesel left, so I should be dry in about a month or two, so there is time to formulate arguments to stop me. My largest fill up to date has been 50L and I've never seen the yellow light, time to see if it works.

[TardisDeli]

Dude, if you run the tank dry you'll run the filter dry. If you run the filter dry you'll have to fill it up again and purge the air from system. Which is a pain, especially on diesel engine.

The voice of experience ... and no it wasn't the delica but another diesel that I learned from.

Cheers, Jay.

[Adam]

Dude, if you run the tank dry you'll run the filter dry. If you run the filter dry you'll have to fill it up again and purge the air from system. Which is a pain, especially on diesel engine.

Well that's not a bad reason. I have run dry on WVO, but I have a aux fuel pump installed to help move the WVO along, so I guess it is not the same thing. It sounds like running dry might end up being a bit of a pain in the ass, but I don't mind priming my fuel filter again, and the air should be purged through the return line. Not like with my WVO return line, which is teed into my WVO supply line. Can't purge air from that without switching to diesel.

If a dry fuel filter and having to pump some fuel through the dry lines is the worst thing that will happen I'm still going through with it.

[jessef]

My reasoning behind doing it my way (see above post)

Long distance driving. I need to know what that tank/tanks can handle right down to the last fume.

It's not for everyone and 99% of people couldn't care less driving in the city.

I'm heading down to south america. I've been central many many times and have come across town after town with dry pumps and I have to rely and what I have.

Hence figuring out exactly what it pulls and how many km's I can get on average.

That about sums it up.

Jesse

** THREAD HIJACK **

ps. My Chamonix (granola) is due next week and the superexceed (marshmellow) is due the week after. I'm stoked.

[mararmeisto]

My largest fill up to date has been 50L and I've never seen the yellow light, time to see if it works.

Even when the little light comes on, there is still 7 litres of fuel in your tank.

From what I understand, it's the 'gunk' at the bottom of a fuel tank (diesel or gasoline) that is the real problem. This particulate and sometimes biological sludge can foul the fuel filter and clog the fuel injectors - and that is where your repair costs come in. Unless the tanks have been washed lately, one doesn't really know what is lurking down there at the bottom of that fuel suction line.

If one runs out of WVO and the engine comes to a stop, I'm thinking there isn't the concern at the start (if the WVO system is a recently installation) because the WVO tank has not had the opportunity to build up with sediment like a 15-20 year-old tank. Also, most installations I've read about bypass the diesel fuel filter (having one of their own), so that is not an issue either. I don't know if this is always the case, but that's what I've read. Please correct if I've got the arrangement wrong because I'm developing an interest in WVO myself.

[docsavage]

My Super Exceed auto will take 75 litres (2 tank system as most here are), tested by running out of fuel. I thought I had enough to get back to town, but I guess not - higher speeds, extra gear and passengers, and wind limited me to 500 km on that tank. Getting the air out of the lines was easy, took only a couple pumps with the primer on the fuel filter, it is much easier when the tank is full. There have been no issues with the fuel pump or anything else. I wasn't to worried about water and grime, but more concerned about running the fuel pump dry, but it stalled out before that could have gone on long.

James