Stay in Place

[rossboyer]

Reminder: Many if us treat our fuel for condensation water and algae in the winter. I did that for our snowbird stay this winter in Arizona. When I returned home in Indiana, I topped off as I usually do, but today I remembered I have to treat the fuel. Probably will not use motor home until August which is 4 months away from the time I got home. 

[wildebill308]

Thanks Ross. Made me think and realise I have never added biocide to my new to me coach. Lots to do to make shure that all the maintenance items are zeroed out.

Bill

[five]

Any time I refuel, and the MH will sit for a while, I add a biocide.

[wildebill308]

I add Diesel Kleen as recommended by Cummins every time and depending on location and weather add the biocide.

 https://www.cummins.com/news/releases/2017/05/10/cummins-inc-officially-recommends-power-service-diesel-kleen-cetane-and

Bill

[sunlover19]

I use liquid dynamite diesel fuel additive www.dynomitediesel.com in my 2005 ISL 400 and have had great results with it. One 16oz bottle treats up to 400 gallons 

Disperses water, boosts cetane levels, prevents fuel gelling, etc.Tier 4 complaint/ DPF approved 

 

[jleamont]

Any engine with a DPF (2008 and up) you do not want an additive that displaces water, said another way; breaks it down to allow it to pass through. Its better to send it into the primary fuel filter and drain from there. If you have that much water you have bigger problems. If it gets blended into the fuel and sent into the injection pump or injectors it will destroy them due to the extremely high fuel pressures within those components and the water doesn't lube where lube is critical under those pressures. Yes, the slightest amount of water molecules will cause premature failure of those components, and they are expensive! 

If you notice the link above, neither product displace water, the concept is to thaw it (if present in the tank), send it into the primary filter to be disposed of. Also by adding a product that breaks down water and allows it to pass through will void the fuel system warranties. Most dealers now are pulling fuel samples prior to performing warranty work. 

[wildebill308]

 

sunlover19, Diesel Kleen as recommended by Cummins. It is the only one recommended by Cummins

 https://www.cummins.com/news/releases/2017/05/10/cummins-inc-officially-recommends-power-service-diesel-kleen-cetane-and

Bill

[rossboyer]

I have a 2005 Cat C-7. I use the biocide recommended by Brett Wolfe. Also, I use Howes one a year. This year twice. May or may not need it, but for 12 years it has not hurt. 

[rayin]

4 hours ago, jleamont said:

Any engine with a DPF (2008 and up) you do not want an additive that displaces water, said another way; breaks it down to allow it to pass through. Its better to send it into the primary fuel filter and drain from there. If you have that much water you have bigger problems. If it gets blended into the fuel and sent into the injection pump or injectors it will destroy them due to the extremely high fuel pressures within those components and the water doesn't lube where lube is critical under those pressures. Yes, the slightest amount of water molecules will cause premature failure of those components, and they are expensive! 

If you notice the link above, neither product displace water, the concept is to thaw it (if present in the tank), send it into the primary filter to be disposed of. Also by adding a product that breaks down water and allows it to pass through will void the fuel system warranties. Most dealers now are pulling fuel samples prior to performing warranty work. 

Correct! Every diesel engine mfgr. I know of states what you just said in their operators manuals. Water in fuel WILL ruin modern injectors.

I might also say, adding anything to a fuel tank after filling is almost useless, as it  cannot mix with contents.

I wonder how farmers get by parking their combines a year without any problems?

[richard5933]

Interesting, the difference between those of us with vintage coaches and those with modern motor homes. I often see videos of someone rescuing a 50, 60, or 70-year-old coach. When they check the fuel in the diesel tank, often it's discolored and old, but unless there is a leak allowing water in there is not usually a lot of water in the tank, if any at all.

Doesn't seem like moisture should be able to enter a closed system. There is only so much moisture in the air above the fuel, and no matter how many cycles of heating/cooling take place it's just the same moisture that's forming condensation over and over again.

My tank has a drain at the bottom where it's possible to check for water. For those without a drain like this, it's possible to use testing paste to check for water in the bottom of a tank. Just smear a little on the end of a dipstick, insert into the tank, and pull it out. If there is water in the bottom the paste will change color. https://www.amazon.com/Kolor-Kut-Ounce-Water-Finding/dp/B00905UC5E/ref=sr_1_3?crid=174OMFHIL7JV9&dchild=1&keywords=water+finding+paste+for+fuel+oil&qid=1587658768&sprefix=water+finding+p%2Caps%2C244&sr=8-3

The other thing to check periodically is the fuel filters. Many filters are designed so you can drain a little fuel from the bottom of the canister to check for water, and others are translucent so it's possible to visually inspect.

Whether it's via the dipstick/paste method, checking the tank drain, or checking at the fuel filters, determining if you have water in the tank should not be difficult. If there is none, then the worries are less. If you find water, then you can take appropriate action (like draining it out.)

Bottom line, physically checking for and then removing any water found is the surest way to avoid problems.

[dickandlois]

Richard, You are correct about the amount of water that can condense in a full tank of fuel. However! all systems need to be vented and as the air in the tanks expands and then contracts over a 24 hr. period. Air in the empty space expands and is replaced equally depending on the real fuel level(s) this allows for humid air to be dawn it to low pressure area of the tank until the interior pressure matches the exterior pressure. If this did not happen then the fuel tanks will fail from flexing or a input point or exit point failing in some manner.

No air being allowed into a tank would eventually stop all fuel from flowing.

As for just dipping a stick into many fuel systems is impossible because of the bends in the plumbing restricting any solid measuring device from entering a tank, let alone touching the bottom.

Rich.

[jleamont]

The biggest issue with moisture entering is hot fuel exiting the engine returning to the tank where the air is cool and creating condensation. Richard, older diesel tanks had the sump on the bottom, old maintenance practices were to drain off of the bottom at each service to remove water and dirt. Not sure why that went away, I can only assume it was something EPA related. I can speak from experience, one could make one heck of a mess draining those if not careful and lose fair amount of fuel, which back in the day wasn't an issue, now a days you could anger a customer if something went wrong.

Most newer tanks have filters on the vents that require replacement annually, those are designed to allow air flow into the tank but not dirt, when they clog (and boy do they, especially in winter, they ice over) it can become a real nightmare, especially if a unit has two tanks.