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Re: Gas tanks and fuel economy
Posted: Thu Apr 24, 2008 8:21 am
by BCDelica
Jesse's plan to drop his tanks, clean/line them, which definitely can't hurt. With the concerns, not just for water build up but softening of fuel lines and tank coatings, over ULSD and biodiesel; why not drain a gallon or 2 from the bottom of your tanks? Easy enough to do ever year and at the least gives you a visual indication of what's happening; do so when your changing diff fluids. Put it in your house oil tank or add it to your WVO before processing; or never have a problem starting a camp fire again. Of note the pickup screen, which is quite fine and arrives with stuff caught it's outside, inside the tank has float valve (check valve) to (help) stop flow instead of drawing anything that's not fuel from inside the tank.
Just put $50 in for the first time this year, goto wonder what's happening in the tank when you can get half a year out of a fill eh Adam.
Re: Gas tanks and fuel economy
Posted: Thu Apr 24, 2008 9:01 am
by Adam
mararmeisto wrote: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.
I just don't see why gunk at the bottom of the tank would be allowed to accumulate if the fuel pick up reaches to the bottom of the tank.
mararmeisto wrote: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.
You are right both points, my WVO install is less than a year old and I have a 5 micron heated fuel filter installed in the WVO system, separate from the stock 10 micron diesel filter.
The only problem I see with me running my tanks dry is that a residual amount of WVO gets flushed into my diesel tanks whenever I switch back to diesel. The less fuel I have in my diesel tnak the higher concentration of WVO and the harder cold starts will be. If this ends up being a problem I'll go as long as I can then try to drain the diesel tanks and see what's at the bottom.
Re: Gas tanks and fuel economy
Posted: Thu Apr 24, 2008 9:51 am
by ghmorris
My 2 cents, take it for what its worth.
Heavy stuff, like coarse sand or larger will likely not get stirred up enough to be picked up by the fuel intake pipe. This pipe is not right on the bottom in most tanks, there is usually a small "dead" area below it. Exceptions would be tanks with a sump area that the intake pipe extends into.
If you take your Deli off-road, or even enjoy rapid back road cruising, you are going to slosh fuel around and stir up any water and small sediment. You are going to pull this into the intake, the screen will stop the largest particles. This 'sloshing' action will be more effective the lower the fuel level is in your tank.
On the trip back to ON we decided to check both the fuel gauge and idiot light. Gauge read exactly in the middle of the empy marker when the idiot light came on, then we ran 30km with the idiot light on. Took 69.95L to fill to the brim which would suggest there was still something like 5L in the tanks.
When we got home, changed the fuel filter and cut the old one apart looking for signs that we had picked up any significant amount of crud from the bottom of the tank. Found nothing unusual.
I expect if we pulled the tanks and flushed them we would find some amount of coarse material or a hardened layer of crud in the bottom. Based on our experience, I'm comfortable that there is little to no small, loose stuff lying in the bottom of the tank.
BTW, running down to when the idiot light just starts to flicker requires right on 60L to fill to the brim. We carried a spare can with 20L with us on the trip to allow for some experimentation.
Question: Is there any reason we couldn't install a vacumn gauge between the fuel filter and lift pump? This is standard marine practice so you know when your fuel filters start to clog. Makes deciding when to change them really easy...
Question: It looks like one of the dash idiot lights indicates water contamination in the fuel filter bowl. Is this correct, and does it work well?
George
George
Re: Gas tanks and fuel economy
Posted: Thu Apr 24, 2008 11:21 am
by Green1
there is little to no risk associated with running a tank empty (any sediment that you might be worried about is just as much of a risk normally, as is any water, the fact that you are running to empty doesn't change that even in the slightest)
For anyone who still doubts this, any sediment or water in a diesel tank tends to settle to the bottom, your pickup is already on the bottom, so it's all able to be picked up normally, for the person talking about a "Dead zone" below the pickup in the tank, if you run it empty the pickup doesn't get any lower, it still won't extract from that area, so the fact that there is junk down there won't change anything.
The only things that could pose any hazard are things that float on diesel, generally we don't find much of that, and your fuel filter will deal with them just as well as it deals with any other "junk" in the diesel.
The only risk is in the priming system, you might want to play with that ahead of time and make sure you know how to prime it, and that the priming pump is actually working before doing your experiment, (it took me about 4 hours to figure out the one on my last vehicle, haven't had to try the Delica one yet!)
Beyond that, one caution about the findings, just because you find that your tank is "X" litres, or you can travel "Y" kilometres on it really means nothing for planning a long trip, mileage varies by far too much for various reasons, so just because you got 700km on it on your test run, doesn't mean you will necessarily make it to that next gas station 650km away...
Re: Gas tanks and fuel economy
Posted: Thu Apr 24, 2008 11:27 am
by marsgal42
ghmorris wrote:Question: It looks like one of the dash idiot lights indicates water contamination in the fuel filter bowl. Is this correct, and does it work well?
I call it the "acorn light". Yes, it's the water separator warning light.
Never seen it go off.
...laura
Re: Gas tanks and fuel economy
Posted: Thu Apr 24, 2008 11:33 am
by Green1
I've never seen the water light turn on, however if it does you are supposed to drain the water from the fuel filter.
Re: Gas tanks and fuel economy
Posted: Thu Apr 24, 2008 5:18 pm
by jessef
Priming the Delica/Pajero 2.5 is easy.
Facing the engine away from the batteries on the filter cap, you'll see a white plastic knob the size of a quarter. Unscrew it, pops out and pushes in and out like a plunger. Undo the fuel line right under neath and start pumping away (make sure you have a pop bottle or something to catch the fuel coming out). Pump until only fuel comes out and no air. Push in, screw on. Start.
Jesse
Re: Gas tanks and fuel economy
Posted: Thu Apr 24, 2008 5:25 pm
by ghmorris
marsgal42 wrote:ghmorris wrote:Question: It looks like one of the dash idiot lights indicates water contamination in the fuel filter bowl. Is this correct, and does it work well?
I call it the "acorn light". Yes, it's the water separator warning light.
Never seen it go off.
...laura
Thanks Laura, hope we never do see it. We are pretty careful where we buy diesel, try to stick to the higher-volume stations that shouldn't have much water in their tanks...
George
Re: Gas tanks and fuel economy
Posted: Sat Apr 26, 2008 8:03 pm
by Erebus
jfarsang wrote:Run dry. Pull over. Prime. Start. Calculate.
Might I suggest adding another step after "Pull over" and that would be "add diesel"?
Sorry, I just couldn't resist.
Re: Gas tanks and fuel economy
Posted: Sun Apr 27, 2008 11:35 am
by northvanman
Greetings,
There's strength in numbers!
I am also form North Van and I'm looking ot make a Delica aquisition. The questions raised seem totally valid for me especially with the fuel price situation. I notice that there are a few gasoline fuelled Delicas out there and even some vegetable oil conversions on the North Shore. Diesel is said to have economic and mechanical maintenance advantages. The price of diesel is as high as gas but if the vehicle is to be driven significantly, Diesel wins and I would expect that the fuel can be found almost everywhere the larger trlucks need to travel (I hope I don't find out the hard way that I'm wrong!)
Cheers,
Bruce
Re: Gas tanks and fuel economy
Posted: Sun Apr 27, 2008 12:55 pm
by delicat
Bruce,
As most of us said, it's pretty simple; 12L/100km on a average city/hwy if you drive reasonably. It's up to you to decide if it's up to your expectations! No, they are not the most economical vehicle but for a 7 seater 4WD vehicle, that in my book is very decent!
Good luck in your acquisition!
Re: Gas tanks and fuel economy
Posted: Sun Apr 27, 2008 1:22 pm
by FalcoColumbarius
According to the NZ manual (translated from the Japanese manual), the automatic transmission Delicas hold 75 litres of fuel; the manual or standard transmission Delicas hold 65 litres; the gasoline versions hold 56 litres. The Miss Lil' Bitchi (my van) is an automatic, therefore 75 litres. The little amber fuel pump on my instrument cluster lights up roughly after using up 58 litres of fuel, leaving 15+ litres in the tanks. Figuring that I average 8.5 kilometres per litre (city driving) I should have roughly 128 kilometres or more of city driving left in the tanks.
To figure what your kilometreage is: - Fill your tank(s) with diesel.
- Set your odometer to 0.
- Drive around until your little amber fuel pump lights up on your instrument panel (if you get to 550 kilometres and the light hasn't come on then perhaps the bulb is burnt out. Go directly to a fuelling station).
- Fuel your tank(s) right up and make a note of how many litres you have put in.
- Take the number on your odometer, divide it by how many litres you have just put in and that will tell you how many kilometres per litre you are consuming, i.e.; 528 kilometres divided by 58.415 litres, equals: 9.038 kilometres per litre.
Using this model I should have sixteen and a half more litres of fuel left in the tanks, ergo: 16.5 Times 9.038 equals: I should have roughly 149.127 more kilometres of driving left in my tanks.
Nota Bene: The size of your tyres will determine the accuracy of your speedometer/odometer readings. Mine are 235/75R15's. According to my GPS & other postings on this site my speedo is accurate.
Falco.
Re: Gas tanks and fuel economy
Posted: Sun Apr 27, 2008 2:41 pm
by jessef
FalcoColumbarius wrote:According to the NZ manual (translated from the Japanese manual), the automatic transmission Delicas hold 75 litres of fuel; the manual or standard transmission Delicas hold 65 litres; the gasoline versions hold 56 litres. The Miss Lil' Bitchi (my van) is an automatic, therefore 75 litres. The little amber fuel pump on my instrument cluster lights up roughly after using up 58 litres of fuel, leaving 15+ litres in the tanks. Figuring that I average 8.5 kilometres per litre (city driving) I should have roughly 128 kilometres or more of city driving left in the tanks.
To figure what your kilometreage is: - Fill your tank(s) with diesel.
- Set your odometer to 0.
- Drive around until your little amber fuel pump lights up on your instrument panel (if you get to 550 kilometres and the light hasn't come on then perhaps the bulb is burnt out. Go directly to a fuelling station).
- Fuel your tank(s) right up and make a note of how many litres you have put in.
- Take the number on your odometer, divide it by how many litres you have just put in and that will tell you how many kilometres per litre you are consuming, i.e.; 528 kilometres divided by 58.415 litres, equals: 9.038 kilometres per litre.
Using this model I should have sixteen and a half more litres of fuel left in the tanks, ergo: 16.5 Times 9.038 equals: I should have roughly 149.127 more kilometres of driving left in my tanks.
Nota Bene: The size of your tyres will determine the accuracy of your speedometer/odometer readings. Mine are 235/75R15's. According to my GPS & other postings on this site my speedo is accurate.
Falco.
Falco,
That's a bit incorrect.
The two tank system in the auto is 75L according to the manual.
Just because you used 58.5 L of diesel, doesn't mean you have 16.5L left that is usable.
When you run a tank dry, there will always be some fuel left residing in the tank so it would be more like 12 liters or so that is actual usable diesel.
Jesse
Re: Gas tanks and fuel economy
Posted: Sun Apr 27, 2008 10:50 pm
by FalcoColumbarius
jfarsang wrote:
Falco,
That's a bit incorrect.
The two tank system in the auto is 75L according to the manual.
Just because you used 58.5 L of diesel, doesn't mean you have 16.5L left that is usable.
When you run a tank dry, there will always be some fuel left residing in the tank so it would be more like 12 liters or so that is actual usable diesel.
Jesse
I will check that out, Jesse. Thanks for the input... smiles.
Falco.
Re: Gas tanks and fuel economy
Posted: Mon Apr 28, 2008 12:26 pm
by mararmeisto
ghmorris wrote:Question: Is there any reason we couldn't install a vacumn gauge between the fuel filter and lift pump? This is standard marine practice so you know when your fuel filters start to clog. Makes deciding when to change them really easy...George
No there is no reason you couldn't install a vacuum gauge...
The reason a vacuum gauge isn't installed in vehicles (I would theorize) is because maintenance is based on a distance-traveled criteria, whereas in the marine environment it's either hours-based or requirement-based (hence the use of a vacuum gauge). Or another way of looking at it is preventative maintenance versus corrective maintenance - change it just before it's a problem, or change it when it is a problem.