Winter Fuel for dummies?!?

[brokenot]

This will probably get me flamed, but the condensation issue is really over-exaggerated. Yes, it occurs. Although it doesn't help matters any, it also doesn't cause the majority of moisture issues you'll see inside a fuel tank.

On a boating forum I also frequent, one of the members was hawking a product he just put on the market that was designed to deal with this issue. He showed some photos of moisture that had been removed from some tanks and concluded that it was somehow *automatically* condensation that had occurred after the fuel was in the tanks. His invention was a device that closed off the fuel tank vent unless the engine was running.

His "data" included details about how much moisture had accumulated, how long it took, etc. I asked him if he'd done any real math, and he didn't know what I meant. I was referring, (of course), to how many times a fuel tank that size would need to "inhale", (via the vent), a volume of ambient air, then wring out every possible drop of moisture it could contain, then "exhale", (via the vent), that volume of air so it could inhale a fresh volume and repeat the process....over and over. Even when using worst-possible-scenario conditions of humidity, the math still didn't make sense. And even if you could envision a scenario in which there was enough moisture in the ambient air to produce the amount of "condensation" he was seeing, you still have to explain the fuel tank's necessary tendency to pull in outside air, wring out the moisture, and keep repeating the process over and over....in order to wind up with the amount of moisture he was attributing to condensation after the fuel was already in the tank. In the area of the country where he resided, he thought daily temperature swings of 20 or 30 degrees F were "extreme" somehow, but around here that's nothin'.

Does condensation in the tank occur? Sure it does. But the majority of stuff I own never sees 1/2 tank or more indicated on the fuel gauge. And yet I have less, (actually...none), of the "condensation problems" that a lot of other folks do.

Same thing applies to the stuff I see daily at work. One customer will have all sorts of moisture-related problems, while another one does not. Same weather, same ambient conditions, same tendency to operate the machinery with the fuel gauge closer to "empty" than "full", etc. If it were truly all attributable to condensation that occurred after the fuel was in the tanks we'd see much more consistent results form customer to customer than we do.

(I know this isn't an "ethanol thread", but the boating forum guy was also touting his product's *obvious* benefit because having a closed vent would also prevent E10 users from having to worry about their ethanol "sucking" moisture out of the ambient air. His math didn't add up there either though.)

 

[BigSteve63]

Couple of things from someone who has been in the fuel business for a while:
1. Most fuel systems on trucks (not sure on boats and/or tractor models) return warmed fuel back to the tank, replacing the tank heaters of days gone by. As the fuel in the tank runs down, you have more tank surface area (which is cold) that can and will allow condensation to form from the warmed fuel in the tank. All of our drivers are instructed to either stay topped off or run on the top third of the tank capacity to help mitigate this problem.
2. Rule of thumb for winterizing fuel - for every 5 degrees reduction in operating temperature, blend 10% #1 or Kerosene with the #2 diesel fuel. #2 fuel at our local rack source is good to about 10 degrees F. When we expect to get to 0 degrees, we blend to 80/20. Couple of times this winter, we were at 60/40.

One thing to remember - fuel efficiency drops off when blending #1 into you engine fuel; using additives will prevent this, but you need to consider the costs of the additive. Considering an average of .10 spread between #2 and #1 fuel, treating adds about one cent per gallon for each 10% blend rate. Some additives are more than this some are less.

Hope this answers at least a few questions for someone!

 

[Jay4200]

This will probably get me flamed, but the condensation issue is really over-exaggerated. Yes, it occurs. Although it doesn't help matters any, it also doesn't cause the majority of moisture issues you'll see inside a fuel tank.

I agree - I don't think condensation is much of an issue for fuel contamination. HOWEVER, there is a very real issue with rust formation inside a metal tank. That's the real issue, IMHO.

JayC

 

[doxford jim]

After reading through this thread, I didn't see too much mention of housekeeping regarding fuel.

With diesel fuel it is imperative that the fuel be kept as dry as possible. Diesel is hydroscopic and has the ability to absorb moisture (don't ask why, I don't know, I'm just stating facts). Keeping the containers - 5 gallon or 45 gallon,clean, dry and away from water/rain/melted snow etc helps a lot..

What I try to do is time my fuel filter changes to coincide with the start of winter - this is handy for a few reasons.

1) You will see evidence of water before it can do damage.
2) You know the fuel filter will be new and clean starting out the winter
3) If there is evidence of water contamination, now is the time to drain your fuel tank and clean it - while the weather is still above subzero temperatures.

As others have said, buy your winter diesel from a busy fuelling station - they are likely to have better filtration equipment = cleaner fuel.

Winter diesel fuel ( #1) is drier than summer fuel with the paraffin wax ( #2). The wax precipitates out and causes clogging - often accompanying freezing condensation. The "cleaning " of #2 diesel to give #1 diesel also removes most of the lubricating qualities of the fuel (sulphur, wax etc.). For this reason, it is very imprtant to use and additive to lubricate the injectors to prevent needles sticking.

I recently had just that happen to me when using my tractor and rear mounted TPH snow blower. I had fuel in my tractor from a newly opened 5 gallon can and had been using it (blowing snow at 2000 rpm engine ) without any problems for about an hour when the engine started to misfire and smoke badly. With the revs reduced to 1000 rpm it would smoke really badly (rich black smoke) - as if fuel was being poured into the cylinders instead of being atomized. I thought I had one or two injector needles sticking open (not shut and on the needle seats). I had no spare injectors so I put a very large dose of Power Service into the fuel tank and added a bit more fuel to mix - from the same 5 gallon container. Started up the tractor - just as it banged, vibrated and smoked badly initially. As the fuel treatment worked it's way through the transfer pump and injection pump to the injectors, you could see and hear the difference. The smoke cleared, the engine rpm's smoothed out and within a couple of minutes it was just purrin just nicely.

I am convinced that the lack of lubricity in the winter diesel had caused my fuel injector needles to start to hang up or stick. The only thing I did was add fuel treatment. Earlier the engine ran fine untill it started to misfire (?) and smoke. The outside temperature at that time was about 10F or -13C which is not too cold really. I had been using another additive "Kleen Flo" which is supposed to help prevent gelling - but it seems, does little to help lubricate the injector needles.

So, what I am trying to say is additives alone help, but don't prevent winter fuel trouble. I did not consider lubrication enough when using winter fuel - now I do.
I have also ordered a couple of spare fuel injectors just in case - at least then I have two spares should the need arise.

Hope this helps someone else having to go through similar problems.

Cheers

Jim