Fuel Contamination

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That slot pretty much defeats the purpose of having the raised pipe to keep water out. My diesel filler caps have chains to keep them aboard and do not interfere with the pump nozzle, so why have the slot?
 
A picture is worth a thousand words.. there is the culprit. get a set of new deck fills and get rid of that slotted neck and bad caps!
HOLLYWOOD
 
Thanks again.
Before replacing fillers I’ll try koliver and smitty477 ideas, lithium grease on threads and JB Weld on slot. Already fabricated a new gasket.
Makes one wonder about the thinking behind the design.
Gonna get a 12v fuel pump and try extracting the water w/ a copper tube set up as suggested. My Kolor Cut arrives tomorrow ��.
 
Is the slot by design or an aftermarket alteration? Be very careful with a patch job. JB weld chunks blocking the fuel pickups would be no fun. Until you follow Hollywood 's recommendation, suggest you drop a well matched O ring over the male end and tight with deck and screwed down cap.
 
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Yup, that fill needs to be replaced immediately with a proper one. The gasket in the cap seals around the top rim but the slot is on the side. There is no way that is water tight.



Also unless you pretty much drained your tanks and refilled only with service station diesel, there is no way any of the diesel coming out of the tanks would not be tinted red.


Ken
 
Seems likely the source of water has been identified - not service station diesel!!
Was the boat on the hard recently, perhaps leaning slightly so that rain water collected near the fill cap? Did you wash the boat aggressively and indirectly pour water through the slit? Does the boat naturally list in the direction of the fill cap? Because even if the fill cap slit is the culprit, it is hard to see why it would suddenly allow gallons of water into your fuel tank, especially since (presumably) it had not do so previously.
 
OK. I'll be the outlier here. Being that they built over a thousand Mainship 34s in the 70s and 80s, I don't think the slot in the threads is a problem at all, as long as the cap is on tight. IIRC, the fuel fill and cleats are on a raised portion of the deck.

The only good thing about flush fuel fills from a design standpoint, is that they are flush. Otherwise, they are completely dependent upon an O ring.
 
Our solution to the usual leaking deck fill was simple.

We remove the fill from the deck and cut in for a 6 inch bronze plate.

The deck fill was tossed for a pipe nipple that fit into the existing rubber fill hose.

The nipple is capped with a std plumbing cap, no capture chain, its only a buck or two at a box store.

As a screwdriver will not remove the deck plate there is less worries about fuel theft , or marina jokers with a water hose.

The lower buck solution would select a plastic deck plate.
 
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As some others have noted, do not use a copper pipe to draw fuel from the tank, copper and aluminum are galvanically incompatible, dragging the copper across the bottom of the tank will leave copper residue, and in the presence of water, this can lead to corrosion of the aluminum. Adding rubber to the end of the tube works but plastic tube would be even better.

Making certain you get all the water out is critical, just a cup or two can lead to corrosion while supporting biological growth. If the fill does not drop directly into the tank then installing an inspection port on the tank side or top may be necessary. These are available as a kit off the shelf, made by Sea Built out of Seattle.

I've been working on boats for over 30 years and I've never seen a deck fill like that, being raised makes good sense, except it's a toe stubber, however, the slot simply defies logic.
 
Hello all,
First outing of the season this past weekend and had a fuel contamination issue. Fuel tanks were topped off before a final 6.5 hour trip to home port last Fall. No issues on trip home and clear bowl for winterization. I topped off tanks again before storing boat inside for the Winter using 5 gallon diesel jugs purchased at a filling station, about 20 gallons total. This is where I suspect I got my bad fuel.

I ended up draining over a gallon of water(?) so far from Racor bowl while underway on a 2.5 hour trip. This is a first for me and bit disconcerting. I feel I was lucky to have discovered it before we had a big problem. At one point I saw no red fuel in the bowl. It raises a handful of questions.

1. What would/could have happened if this went undiscovered? I figure the engine would start running rough before shutting down giving me an opportunity to investigate. Worse case?

2. Now what? I need to know the water (or what else could it be?) is all out before setting out again with peace of mind. Is a fuel polishing advised/required? If so, (please excuse my ignorance on this), is that typically a mobil service that comes to your marina? What about running the engine and gen-set in the slip until I don’t have to drain the filters any longer? If the boat sits, won’t the water settle to the bottom and be unreachable by the fuel pick up? Next time we’re out the water sloshes around, mixes with the fuel and we have the same issue.

We’ve had the boat, 78 Mainship Mk1 for about three years. Two original 110 gal. aluminum tanks. I know clean fuel is critical and I have been changing filters, adding algae treatment and watching the bowl but that’s it. I’m still learning and would appreciate any thoughts and advice.

Thank you so much in advance,
Steve
Doubtful of that being water, it would most likely be the clear or yellow diesel you got at the gas station. If that was water in the level your engines would be DEAD.
 
water in fuel

I knew as soon as I saw the fuel fills what kind of boat it was.I have a 1981 MS 1 . You can stick the tanks from the fills. get some water paste and stick the tank. to the bottom. You will need something a little flexible. this will tell you if & how much water you have in the tank. You should be able to suck most of it out. It's the place to start.
 
water in fuel

The fills are raised on the deck, not much chance of getting water in that way. caps should have O rings ,should be able to match them up at a good auto store.Good luck
 
There are sensors that can be added in a filter housing that detect water in the fuel and sound an alarm.

I doubt it's the auto diesel. I use it when ever I get access to a dock a fuel truck can use. Auto diesel is in my boat now.

If your cap doesn't fully cover the slot in the fill neck, water could enter from deck wash downs or rain. Since you're not using the cap chain I'd fill the slot or get another type of deck fill. A gallon of water in a 2.5 hour run is a lot more that I've ever seen. And I've been my own captain since 1961. But most of those years were using a diesel much better than today's. Even so, I never have fuel problems.
Your main engine (Perkins?) doesn't return much fuel to the tank so it won't polish fuel enough while running.
If you add a tee after the Racor and add a pump to move fuel from the main fuel line to the return line you can polish the fuel. You'll need a valve at the tee and a pump that will deliver 25 gallons/hr. or more. You can run the pump while running the main if it has valves. You may need to use a 3x dose of a good conditioner/biocide to clean the tanks.

My Racor 900s have a 2 micron element and get changed at about 500 hours. My mains alone pump 70 gallons/hr and return 60+ to the tank. Do the math. I get less than an shot glass of water in a month of heavy running, but eyeball the filter bowls every day. I use Archoil AR6200, but have also used Algae-X with good results.
Pump (or one like it) in the pic is about $20 on ebay and rated at 35 gallons/hr.



 

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Now for my $0.02 worth.

I agree that your fuel contamination probably came from the filler tube. The slot screams "leak point" to me. I'd replace it asap. Then I would look into adding a fuel polishing system, possibly adding another set of Racors. Anything to keep your fuel clean, because it's d@mned expensive if you don't.



I had a fuel contamination issue about 2 years ago. I took on 180G of diesel of which ~20G was river water (brackish). I didn't know anything was wrong until the engines quit. 2 International 9.0L diesels 3600Hrs ea. aboard a '82 Carver 3607. The engines tried to burn the water and superheated it into steam. This steam melted the rubber exhaust hoses on both engines right at the end of my risers. The bilges couldn't keep up with 2 engines dumping their exhaust cooling water into the bilge. We took on ~14inches of water in 10 minutes. The spray from the water killed both alternators, one starter, all 16 injectors and a rebuild on both injector pumps. Fortunately we were able to start our generator and run an emergency pump to keep us afloat. We made it to a haulout and began the repair process. ~$8000 in damage so far with me doing all the work. I have received $5200 back from a lawsuit filed by the Captains against the Marina. Doesn't help much, but it is something, one couple lost their 2014 70ft Viking. Most insurance won't cover bad fuel damage, since it is the Captains responsibility to obtain good fuel.



My insurance says that they won't cover contaminated fuel unless it is checked for contamination everytime.



Their Procedure that I was given is:

Pour an amount of fuel of no less than 1 gallon into a clear container
Allow to fuel settle for at least 15 minutes
Check for fuel contamination having settled to the bottom of container
If contamination exists then fuel is unacceptable.


Does ANYONE actually do this?!?


My solution is radical. Due to the amount of damage, age of the boat, my skill set, how much my wife and I like the size and layout of Star, and that we own her. We're going to get her to our home port of Baltimore and gut her. New wiring, plumbing, better fuel handling system, active fuel polishing system, new fuel, water & waste tanks, floor framing and decking, add propane, hard bimini over the aft deck, radar arch, hoist for dink, remove all the carpets and replace it with hardwood, etc. A TON of work.
 
OK, never had major fuel issues (thank god) and not a fuel expert but noticed that everyone has focused on water in fuel. What if the fuel purchased at local gas station was in fact gasoline and not diesel? Does gasoline separate out similar to water in the filters? Would it allow the engines to continue to operate without shutting down?
 
A friend of mine once had an engine stall in his single engine trawler while maneuvering in a marina due to water in the tanks, and he ended up with his bow pulpit mounted anchor through the side of a sailboat which was in a cradle at the side of the wall he ran into. Coincident to this stall, his Borg Warner transmission fell off the back end on his Lehman 120 into the bilge. True story.

It was discovered that his decks leaked onto the tops of his tanks which rotted allowing water in every time it rained or spray got on the decks. You might want to pressure test your tanks.

Parker sells the modified bowls for their Racor filers which allow you to mount water detectors to them. They also sell the alarm circuit to make it all work.

I would not own a diesel boat without some sort of water alarm for the fuel system. My current Yanmar has such an alarm screwed into the bottom of the engine-mounted fuel filter.

Speaking of alarms, I wonder if the casualty to the exhast system mentioned above would not have been detected in the early stages with a simple Borel exhaust heat sensor/alarm? Hopefully, the water-in-fuel alarm would have activated well before that, but I have both alarms and the accompanying peace of mind.
 
Thank you again everyone for your posts.
I’ve assembled all the parts for a liquid extraction rig similar to that shown by lepke on his reply. I’ll use 3/8 ID PEX tubing instead of copper, plus a clear inline filter.
Scary stories have me committed to getting every drop possible.
What ever I can’t get I’ll trust the RACOR will get eventually with wave action mixing unreachable water into fuel a little at a time, over time.
Will also look into water in diesel filter alarm and watch filter like a hawk for a long while until I’m once again comfortable.
Will report back.
Again, many thanks.
 
Forget to mention, definitely water as I froze a sample as suggested.
Cheers!
 
My vote is with Tomas and Syjos. Let us know the outcome.
 
"Does ANYONE actually do this?!?"

Probably not , however a few folks will use a Baha filter for the first 5-10 min of a fill, and if no water is found will fill directly.

I have found dirt at times , small water at other times.

Rybovitch used to make Monel deck filters , but WOW! were they pri$y.
 
SKS
Just wanted to confirm you are on the right track w good advice and with due diligence should be fine.

A few yrs back I had somewhere around 5-10 gal water in my 250 gal tank. Won't get into details how but my fault and realized it immediately so never ran the eng.
I could not (easily) get at the top of my tank to use a dip tube. After borrowing a fuel pump from my yard I disconnected my fuel supply (very near bottom aft of tank) and began draining into 5 gal buckets. Continued as long as a noticable amount of water present. I was able to separate out the water amazingly well by decanting off the diesel. An oil pad worked well enough to pick up minor amounts of diesel off the top of an open bucket. Separated diesel was saved and given to my buddy that burns recycle oil for winter heat.
An off line separating filter was hooked up to the pump and returned via my deck fill and I pumped until negligible mats of water were being removed.
Hooked up supply to Racors and ran engine at dock then out on the water monitoring water separation closely and draining as needed. With my pickup at aft of tank getting the bow up while running "helped" pick up more water.
When we headed out for a cruise I monitored Racor periodically to establish a rough idea of need for draining (I could drain mine underway at idle w admiral at the helm).
My drain frequency decreased steadily and got to daily after some steady running. I changed Racor elements and checked 1-2 x day but starting getting very little water.
Bottom line I found the Racors work well and do their job... at least if one doesn't overwhelm them.
By using the tube you should be able to accomplish the initial removal fairly easily... especially If you can list the boat and remove from a tank corner.
Above provided simply as a confirmation that while somewhat arduous the process works and can work successfully.
 
Thanks for the encouraging words Bacchus.
I bought a 12v fuel pump similar the the one shown in the post by Lepke.
With luck it will be able to “lift” the water/fuel about 3-4 feet. If that works (fingers crossed) I’ll get what I can until no water shown on Kolor Cut paste.
Then, as you posted, let the Recor do it’s thing, but with a watchful eye.
 
water in fuel

As I said in my last post, this MS does NOT have a flush fuel fill, it is on a raised mount, and has about a 1in male nipple coming out of that, ! then a proper CAP female thread with a O ring inside, The paper gasket is NG, but still should not let water in unless the deck was under water ! but IF the water did find it's way in , you can still stick the tank through the fill caps, and if you do find water you can suck it out through the fill cap.
 
As I said in my last post, this MS does NOT have a flush fuel fill, it is on a raised mount, and has about a 1in male nipple coming out of that, ! then a proper CAP female thread with a O ring inside, The paper gasket is NG, but still should not let water in unless the deck was under water ! but IF the water did find it's way in , you can still stick the tank through the fill caps, and if you do find water you can suck it out through the fill cap.


What about that slot in the side of the fuel fill? That looks like it is just begging for water intrusion given any type of heavy rain, let alone snow.
 
Someone said it was for the keeper chain so the nozzle could go in... I have chains on my caps and the nozzles go in fine with the chains in place, so I have no clue why they would do that except maybe they were in league with Racor to sell filter elements.
 
water in fuel

I've had my mainship for 15 years stored outside year round,decks have been awash many times. never had a drop of water in fuel. but I will say that I buy my fuel on land, a friend has a pick up with 100 gal tank. fill up at dock. maybe he just got some bad fuel, but still can be sucked out from fuel fills.
 
UPDATE
All the input from your posts well most helpful. I’m very grateful.
I’ve (hopefully) attached photos and a video showing extraction set up and results. I’ll continue and eventually finish when I get more inline fuel filters.
It’s going to be tedious and time consuming but I expect satisfactory results.
With any possibility of intrusion via deck fills corrected, I hope this is a “one-off”.
I will however make a tank dip with Kolor Kurt, a regular practice.
Thank you again everyone!
 
Photos:
 

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SORRY, I can’t figure out a way to post short video.
 

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