You'll all be familiar with tales of modern petrol accumulating water over time due to the ethanol content. Just wondering if anyone has drained the dregs of an empty tank lately and if there was any significant water? Just run one side dry and wondering if it's worth draining completely before I refill.
Cheers
Steve
Should I drain my tanks periodically?
Should I drain my tanks periodically?
57 KB 58 1983 SIII GS Lightweight
Re: Should I drain my tanks periodically?
Hiya Steve! 
,
I've heard it said that if you leave the fuel tank nearly full it lessens the chances of 'Phase seperation' as there is less air gap in the tank for moisture to form in, and create the water that the ethanol binds with. That said, I have no idea how much water it takes the ethanol to absorb before it separates from the fuel itself, and no real world clue as to how long the separation would take.
I leave my Lightweight for quite a while with the tank below half full, and the left tank has been at nearly empty for a while now,(Nearly a year.), and switching between the tanks didn't throw up any running problems two weeks ago when I did it whilst sorting a sender switch fault prior to it's MOT. I don't use any fuel stabilizers, but I do use lead additive, which is a force of habit thing, and the fact that I bought a bulk load of it cheap. I can't tell what's going on inside the tanks on mine as I have 'side fill' tanks so can't look into them like you can on the underseat fill tanks, and the fact that they are custom built out of stainless steel means that they shouldn't rust even if there is a bit of water in there.
As the water would sit below the level of the fuel once seperation takes place, I think the first sign of problems would be running issues with possibly a sign of water visible in the fuel bowl. If you can't see water/fuel seperation by looking into the tank, then cracking off the fuel drain plug in the tank to allow a weep/trickle of fluid out would tell if there is water in the fuel as it should come out first.
Regards,
,I've heard it said that if you leave the fuel tank nearly full it lessens the chances of 'Phase seperation' as there is less air gap in the tank for moisture to form in, and create the water that the ethanol binds with. That said, I have no idea how much water it takes the ethanol to absorb before it separates from the fuel itself, and no real world clue as to how long the separation would take.
I leave my Lightweight for quite a while with the tank below half full, and the left tank has been at nearly empty for a while now,(Nearly a year.), and switching between the tanks didn't throw up any running problems two weeks ago when I did it whilst sorting a sender switch fault prior to it's MOT. I don't use any fuel stabilizers, but I do use lead additive, which is a force of habit thing, and the fact that I bought a bulk load of it cheap. I can't tell what's going on inside the tanks on mine as I have 'side fill' tanks so can't look into them like you can on the underseat fill tanks, and the fact that they are custom built out of stainless steel means that they shouldn't rust even if there is a bit of water in there.
As the water would sit below the level of the fuel once seperation takes place, I think the first sign of problems would be running issues with possibly a sign of water visible in the fuel bowl. If you can't see water/fuel seperation by looking into the tank, then cracking off the fuel drain plug in the tank to allow a weep/trickle of fluid out would tell if there is water in the fuel as it should come out first.
Regards,
For Those That Have Had To Fight for It, Life Has Truly A Flavour The Protected Will Never Know.
'First my weapon. Then my equipment. Then myself.'
Neil.
09FM98. 1973 Ex SIII FFR Now 3.5 V8 LWT Coiler.
55HG98. 1980 SIII FFR PARA RECCE. Ex 1, 2 and 3 PARA.
Td5 90 XS.
'First my weapon. Then my equipment. Then myself.'
Neil.
09FM98. 1973 Ex SIII FFR Now 3.5 V8 LWT Coiler.
55HG98. 1980 SIII FFR PARA RECCE. Ex 1, 2 and 3 PARA.
Td5 90 XS.
Re: Should I drain my tanks periodically?
Hi Neil. Makes sense. I tend to run each tank in turn right out so that I don't end up with really old petrol in either tank. I've also been using e5 ever since the e10 came in, so I am using as low an ethanol content as I can. If I get time this week I'll drain the dregs from the empty one into a transparent vessel and see if any water settles out. I agree with you in that if there's a small amount then it's probably below the level of the pick up - and I've had no symptoms of rough running due to water contamination. But being a mere mortal with mild steel tanks, I'd rather be completely water free in there if I can.
For what it's worth, I'm an unbeliever when it comes to lead replacement additives a) because I'm too mean to fork out for them; b) it'd take me a lifetime with the mileage i do to wear out the valve seats; and if I'm wrong on b then last time I looked, exchange unleaded heads were not silly money anyway - I'll just get the head done IF it ever needs it. Appreciate you would have 2 heads to convert in your case.
I'll report back.
For what it's worth, I'm an unbeliever when it comes to lead replacement additives a) because I'm too mean to fork out for them; b) it'd take me a lifetime with the mileage i do to wear out the valve seats; and if I'm wrong on b then last time I looked, exchange unleaded heads were not silly money anyway - I'll just get the head done IF it ever needs it. Appreciate you would have 2 heads to convert in your case.
I'll report back.
57 KB 58 1983 SIII GS Lightweight
Re: Should I drain my tanks periodically?
Drained the dregs earlier - no water to be found! So I'll keep on doing what I have been as it seems to be working!
57 KB 58 1983 SIII GS Lightweight