Forgot to put additive in diesel tanks before layup

cwiert

cwiert

Active Member
SILVER Sponsor
May 7, 2008
565
Chester, CT
Boat Info
1998 400 Sedan Bridge
Engines
CAT 3116 - 350HP
Like the title says, I forgot to add in an additive/stabilizer into my tanks before the boat was pulled for the winter. This is my first diesel boat, so I'm not sure what I should have used, if anything. On my previous gas boats, i usually would add in Stabil in the fall, and run that through the system for a few minutes prior to winterizing.

Currently each tank is about 3/4 filled with fuel. Should I add anything to the tanks now? Is it too late? What product should I add?

Thanks.
 
Yes.....you need to add about 50 gal of fuel to each side. It isn't too late, but may require hauling fuel to the boat.

Never store a diesel tank unless it is full of fuel. The reason is because your tanks are vented to the atmosphere. That means the empty space above the fuel is filled with ambient air. As the temperature chanced from cold at night to warmer in the daytime, moisture condensed on the interior walls of the fuel tanks. The water droplets run down the tank walls or drip off the top and water collects at bottom of the tank. Since diesel fuel supports microbial growth in the presence of water, you have the recipe for a mess on your hands come spring.

My recommendation is to add a biocide, a lubricity enhancer, a general purpose diesel additive to raise cetane and disperse water, then top off your fuel tanks.

Rather than go thru the entire fuel management process, I suggest you read this article, which is on the home page of CSR:

http://clubsearay.com/content.php/4-Diesel-Fuel-Management
 
Yep Frank is right again. Ask me how I know. I read his diesel fuel article AFTER I had to have my tank polished. No problems since I have kept the tank full and a biocide in the tank.
 
Yep just got caught.
Being a mechanic and picking a boat up from Adelaide, that had seen little use in the last 2 years......
Changing filters in a 2-3M sea, 60Nm from anywhere, is not fun.........yes I can now say I have been seasick in my engine room.


Sent from my iPad using Tapatalk
 
IanBat said:
.....yes I can now say I have been seasick in my engine room.
Click to expand...

(Note to self.... Never be too uptight that your engine space it not immaculate. Could be worse.....) :grin:
 
If the fuel in the tank is ValvTec brand diesel you are fine. I has all the additives you need for winter layup.
 
No he is not fine.

The fuel in his tanks may be treated with the biocide and stabilizer contained in the Valvetect additive, provided his fuel source treated their fuel with Valvetect in the right concentration. But, his tanks are 25% full of air that is condensing moisture inside the tanks every time he has a temperature change. Valvetect may be a good product, but it doesn't protect the fuel in the tanks from external sources.
 
What kind of storage are you in? Heated or cold storage?

If you are in heated storage, I would be far less worried about condensation......
 
Boatingnut said:
What kind of storage are you in? Heated or cold storage?

If you are in heated storage, I would be far less worried about condensation......
Click to expand...

The boat is in cold storage, on blocks outside. The fuel in there is ValvTec. I honestly don't know about the feasibility of hiring a tanker to come and put 50 gal in each tank. I think the marina might frown on that. I'd have to consult with them first. I also don't think the tanks would hold 50g each. The tanks were full, I had one last 3.5 hour cruise (roughly 25 GPH), so 88/2 = 44 Gal missing out of each tank (each tank holds 175). I don't know who I'd get to top off the tanks for that small amount. I will definitely add in the additives that Frank mentioned above. I will inquire about topping off the tanks, but I'm not sure if that is feasible. If not, I'll just have to cross my fingers and hope for the best.

I appreciate all the replies.
 
Given the facts on location, length of layup, this is the least I'd do for each tank.....I'd mix my additives in a couple 5gal cans of diesel and pour one in each tank.
 
The world isn't coming to an end. It could be worse.......what if the tanks were 25% instead of 75% full and what if the fuel in the tanks was not treated with Valvetect additive.

If you did nothing, the worst that will happen is that you will have to clean up the system in about May. In the meantime, I'd suggest you learn how to change Racors.


If you just cannot top off the tanks, then I would add a biocide and a fuel stabilizer (because Valvetect won't tell us what is in their additives) now, then in the spring, add biocide in shock quantity, Diesel Kleen, A lubricity additive and Power service 9-1-1 right before you add fuel to the tanks.
 
It turns out I am in this same position. I actually asked the marina if tanks should be full prior to haul out and was told there was no need to have the tanks topped off. My tanks are only about 50% full.

No way to fill tanks now or add anything to them until spring.

How do you know if there will be an issues in the spring? Is there anything that can be done prior to launch or right when you launch?
 
Zach312 said:
It turns out I am in this same position. I actually asked the marina if tanks should be full prior to haul out and was told there was no need to have the tanks topped off. My tanks are only about 50% full.

No way to fill tanks now or add anything to them until spring.

How do you know if there will be an issues in the spring? Is there anything that can be done prior to launch or right when you launch?
Click to expand...
You’ve only had your boat 1 season I think. The habits of the previous owner might still have an effect.

Things that better your chances are, purchasing good quality/clean fuel, having used additives during the season, using the boat…running some fuel through it. The result is when you put it up for the winter it already has reasonably fresh, clean, treated fuel.

A half full tank does not automatically mean spring disaster due to condensation. The water horror stories that we hear are more likely due to the accumulation from all sources, the easiest and largest potential is from poor fuel supplies. Yes, leaky fill caps and condensation can contribute too. Up our way the winter air is dry, with temperature not as conducive to condensation accumulation and microbial growth.

What did I do? When I took possession this spring I change all fuel filters and heavy dosed my fuel with additives. I continued the additives with each fill and visually monitored the racors for first signs of problems during the season. I had no fuel problems and after season #1 feel I bought a boat with a healthy fuel system.

When I filled up the last time I gave an extra dose of biocide. I burned near half a tank getting to the storage facility and had intended to top off with fuel but didn’t. My boat is sitting in 50F heated storage with a half tank of fuel and I’m not worried about it at all.
 
We had a 28 footer with gas engines. I let it sit 1.5 years before we used it. Got 5 miles out and it died. Was towed in and mechanic sucked out the water in the gas tank, changed the gas filters and told me to change them after 1 hour of running then again in a day.
Assume you will be like I was and have water in the bottom of your tank. Your boat is probably stored at an angle so if you get some fuel sucked out you may get most of the water out. He used the same pump to change oil in the engines.
 
peterkvs said:
You could easily put an inline desiccant drier on the vent line. Then no water would get to the tanks.
Click to expand...

I will defer to Frank and other diesel pro’s for the answer, but I don’t think a dryer would completely solve the problem. As the temperature, dew point, etc change each day and night, the interior walls of the tank will build up condensation. Even the smallest of opening in to the tank would allow the water laden air drops an entry point.

I suppose if you were able to completely, 100% cover the tank openings, it may work, but I am not sure. It is an interesting idea though.

Overall, it’s a good reminder for all of us to keep the tanks full and the fuel treated. I have been guilty myself.
 
Woody said:
You’ve only had your boat 1 season I think. The habits of the previous owner might still have an effect.

Things that better your chances are, purchasing good quality/clean fuel, having used additives during the season, using the boat…running some fuel through it. The result is when you put it up for the winter it already has reasonably fresh, clean, treated fuel.

A half full tank does not automatically mean spring disaster due to condensation. The water horror stories that we hear are more likely due to the accumulation from all sources, the easiest and largest potential is from poor fuel supplies. Yes, leaky fill caps and condensation can contribute too. Up our way the winter air is dry, with temperature not as conducive to condensation accumulation and microbial growth.

What did I do? When I took possession this spring I change all fuel filters and heavy dosed my fuel with additives. I continued the additives with each fill and visually monitored the racors for first signs of problems during the season. I had no fuel problems and after season #1 feel I bought a boat with a healthy fuel system.

When I filled up the last time I gave an extra dose of biocide. I burned near half a tank getting to the storage facility and had intended to top off with fuel but didn’t. My boat is sitting in 50F heated storage with a half tank of fuel and I’m not worried about it at all.
Click to expand...

We had all new filters installed when we purchased the boat and had no issues last summer. We put approx. 85 hours on the boat and ran about 2 full tanks of fuel. We only purchased fuel from a Valvtec certified marina. One thing we didn’t do was use additives. This is something we will consider changing this year.
 
You must log in or register to reply here.

Forum statistics

Threads
113,193
Messages
1,428,278
Members
61,104
Latest member
Three Amigos
Back
Top