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Oil tank treatment

DZoro Member Posts: 1,049
Does anyone have a go to for fuel oil tank treatment. I have a customer that we are having issues with. Comes down to having some possible water mix in the tank. Oil CO. says it's not the oil, so they wont put in any treatment. Only have seen this issue a few times around here, don't have many oil customers left.
Just wondering what I should put in?


  • STEVEusaPA
    STEVEusaPA Member Posts: 4,971
    What has been confirmed visually? I'm assuming you're the person trying to fix the problem and are in the basement.
    Can you drain 1, 2, 5 gallons from the bottom of the tank to see what you have? Or stick the tank with paste to confirm water?
    What type of heating oil-HS, LS ULS...any bio?
    I use the 4 in 1 Hot, but who really knows if it works?
    I carry a case of oil treatment in the oil truck. If someone needs or wants it, they get it. I'm surprised (not really) the oil co. just won't dump a bottle in.
    While I'm doing the annual maintenance (or anytime I do service) if I see water or sludge in the filter, I'll make a note to start treating the tank until it's gone/cleared up.
    It wouldn't hurt to dump a bottle in on every tank, best would be at the end of the season when they fill their tank up before summer (tough to convince people). Second best would be with first fill up in the fall, but before filter replacement.
  • Scott M_2
    Scott M_2 Member Posts: 26
    Check the fill and vent pipe for rot and holes 9 times out of 10 this is the culprit.ALthough one time we found a young lad who liked to play oil man with the garden hose.
  • DZoro
    DZoro Member Posts: 1,049
    Thanks Steve,
    I will order some 4 in 1 hot,
    History on it, ran out of fuel this fall..... So yes the filter was dirty with sludge, tank in the basement, not sure the type of oil, it's a old T-Pride, the wiring diagram was drawn out by hand from the factory :).
    Went through the furnace side carefully checked, and cleaned everything. Hadn't been attended to in many years...

    Called back out, found it was running horrible, it was set up with analyzer, when I left the first time, all good numbers.

    Changed nozzle and seen watery oil, faint yellowish tinge, changed filter not a good color in there either. Like I said we don't have many oils left around here, and the Oil CO. is no help. There is only half a tank, so should I put the bottle in and wait to have it re-filled?
    Or have it filled, and hope for dilution.

    Not a good set up to drain gallons, but will try.

    Scott, I will double check the pipes, check for small oil man tracks ;). Pretty sure non are there, single old man, hoarder house.
  • STEVEusaPA
    STEVEusaPA Member Posts: 4,971
    edited December 2018
    Since the oil was settled, the sample in your filter bowl would've shown the water.
    Assuming your tank valve works, couldn't you just take the oil line off at the pump, or right after the filter, then let it drain into a small bucket? If there's hard pipe filter into the fuel pump, you can take the pump cover off and drain from there.
    You'd really need to drain until you don't see any milky or orange-like oil. Then blow back the line and change the filter element again. But being they ran it dry, you shouldn't really have any water, but the additive would help with the other crap in the tank.
    You could dump it in, but it really needs to be mixed in to disperse water (unless it's a 2 pipe).
    Like you said, you pulled all the crap in when it ran out, but if there is water it is always on the bottom.
    Are they due for another delivery? That would be the time to dump it in.
    Is there an unused bung on the tank? You could pour it in there, and either use a cordless drill with a makeshift paddle to stir it, or use a pump to recirculate a little.
    I would've used the push/pull pump from the burner back to the tank to clear the oil line.

    If you do have access to the tank with an unused bung, I would stick the tank to see how much water is in there. If the tank ran dry, and you have more than an 1" or 2 of water, either someone sabatoged it, the cap was off when it was raining, or the oil company got/gave you some bad oil.

    As an example, new customer, empty tank. I filled the tank, started the heater (who knows when it was cleaned last). 2 days later, no heat, pump whining. Cleared restriction, changed filter, pump strainer had a 1/2" of crud all around, changed nozzle. Ran for about 5 minutes started whining again. Pump strainer, filter (at the burner), completely plugged again.
    Put in additive with push/pull pump at the tank. Replaced nozzle/strainer again, new oil line, & put spin on filter at the tank.
    It's been working a month.

    I'd recommend bottle of additive and fill the tank, every delivery. Or have the H/O dump half a bottle in with 100/125g delivery when the truck shows up before the drop. They could leave the bottle for the driver to dump in, but something tells me the driver wouldn't do it.
  • DZoro
    DZoro Member Posts: 1,049
    Thanks Steve, that's some great advice, really appreciate it. It is single piped, line buried in concrete, so hard to manipulate the line, but will try to purge all the goodies out. ;) small pail at a time. Then will add the additive and, Leave some bottles for the HO to put in before the next fills.
    Again appreciate the advice.

  • Leonard
    Leonard Member Posts: 903
    edited December 2018
    As a temporary solution, till in summer can run it out of oil and clean it for real, maybe :

    IF have an unused port on top, maybe a stiff old plastic garden hose and wet vac to vacuum out some of sludge. Or flexible hose and length of electrical conduit to vac the center length of tank., to get some of water out. Can do this even with oil in tank

    My 275 gal tank in heated cellar had 60 years of condensate in it. When my tank ran empty was 1.5 inch of oil left in tank , and of ~ 9 gallons left, 5 of that was black water condensate.

    Let what you vacuum out sit a few days or week and can skim off clean oil for reuse,
  • STEVEusaPA
    STEVEusaPA Member Posts: 4,971
    After all that, whatever you pump (I wouldn't use a vac) out, don't re-use. Give it someone with a waste oil burner, or dispose properly. As a tech, in the winter, I wouldn't want to make another trip to the house just for that, and secondly make additional problems for 5-10 gallons of oil.

    As I mentioned in other posts, there are companies (mostly generator companies) that have fuel polishers specifically for this purpose. Mostly used for diesel generators where fuel sits for years.
    In Europe, cleaning oil tanks is pretty well known/done. Here, almost never.
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