"Buggy" Fuel Problem

Post here issues with diesel engines on PDQ yachts
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maxicrom
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"Buggy" Fuel Problem

Postby maxicrom » Thu Jun 23, 2011 12:15 pm

With the house project underway we haven't gone through the usual 3 or 4 tanks of fuel per season. Last year we ran the boat about 3 hours total and in my renovation tunnel vision forgot to put stabilizer in when we winterized. II the Max only has the single inboard in the Port hull.

Status: Its a Yanmar 20hp diesel and it fired right up as usual this year, after warm up I left it idling for about a half hour. When I advance the throttle it slowly died. Pretty sure that my filters are full of something - last week I added a "shock" treatment of Biobor mixed with fresh diesel. I'm thinking to let the Biobor do it's thing for another week then start on options to clean things out. This motor has always run like a clock, starts right up, and been very dependable.

With the large flat tank I'm thinking that fuel polishing would be both costly and difficult - I have a small Raycor water separator filter ahead of the Yanmar filters but am considering adding a larger Raycor ahead of it to catch the gunk. The little Raycor clogs pretty fast and the filters are pricey. There is no great access to the fuel tank other than through the sending unit or fittings - I'm thinking it's about 1/2 full going by the gauge "flicker" speed.

Anybody dealt with a similar issue?
Mike & Linda
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Re: "Buggy" Fuel Problem

Postby Page 83 » Thu Jun 23, 2011 12:23 pm

The Outboard PDQ 36 uses the same or similar tank, and after a negligent winter I had to pull mine out and try to clean it. I ended up pouring a gallon of alcohol and carb cleaner into it, rotating the tank many times, pouring it out and then blowing it out with the exhaust end of a vacuum cleaner. Then iot was dry. I was shocked by the crap in the alcohol I removed. After all that work, I should have known better that to neglect it again this past winter. Sigh.
Sandy Daugherty "Page 83" PDQ 36026

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Re: "Buggy" Fuel Problem

Postby SecondWind » Thu Jun 23, 2011 2:29 pm

I agree with Sandy, pull the tank and clean it, then keep Biobor in it all of the time. I had the same problem a few years ago when I added "Starbright Diesel Cleaner" to my fuel. Broke everything in the tank loose. I could not keep enough Racor filters on hand. I also built a fuel polishing system using a Racor 500/ electric fuel pump/ plus assorted valves and fittings. Never had a problem after that.
Terry Green
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Re: "Buggy" Fuel Problem

Postby maxicrom » Thu Jun 23, 2011 10:32 pm

Jeez,
I was hoping someone had a whiz-bang answer like pour some "new and improved super Dezo-Cleano" and all would be good as new... Guess not - :roll: I'm thinking the sacrificial larger Raycor will at least let me run long enough to get the fuel down enough to drain it and do a good clean out. We probably have about 20 gals or better in there now.

I've considered but am hesitant to remove the sending unit do a visual check on the tank - it doesn't leak now and I'd hate to strip out one of the screws. Anyone had any experience with this?

I'm guessing that most PDQ's have the same style flat tank under the cockpit sole - do any of the later models actually have a fuel gauge that gives a useful reading? Ours correctly reads "Full" and once the level drops a bit basically floats between 3/4 and E and is really not very useful - probably not much can be done with a flat tank. We count on our log to determine how much fuel we need and to avoid overfilling.

Thanks for the responses,

Mike
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Re: "Buggy" Fuel Problem

Postby SecondWind » Fri Jun 24, 2011 7:19 am

We went to an electronic sending unit made by Snake River electronics. Search for an earlier post to get the details. viewtopic.php?f=15&t=2178&hilit=sending
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Re: "Buggy" Fuel Problem

Postby thinwater » Sat Jun 25, 2011 4:53 pm

Having been around the fuel and petroleum testing business business for 29 years, I have a few thoughts.

* How do you know it is a bacteria (bug) problem? The best way is a test kit. Alternatively, does the stuff in the filter feel like wax or snot? Snot is bugs.
* Generally stabilizer has little to do with infection (have done the tests). Infection is prevented by dry fuel, sterile fuel, and maintenance biocide treatment. You may have simply gotten some bad fuel. However, bacteria from the air can do it too.
* Bacteria grow in diesel, but not in gasoline (too toxic, NEVER happens). E-10 separation problems are not related.
* Pumping gasoline is FAR more hazardous than many realize. I have done accident investigations where the ignition source was proven to be nothing more than static from pumping. When it is handled in the normal manner--hose to tank--it is fairly safe, because the fixture is flooded, but cleaning gasoline tanks requires EVERY conceivable precaution. Unless you have rated equipment, having power equipment withing 15 feet is questionable. Use a hand pump and wear a vapor mask. There have been numerous fatalities.
* Yanmar actually prohibits biocides in the manual, specifically shock doses. The problems is that some of the bacteria are in the fuel lines and past the filter, and they will all slough off at once. What you need is a maintenance dose; that is how the airport uses Biobor JF (for jet fuel, of course).
* Fuel polishing is going to cost more than the fuel is worth (dump it in the used oil tank at the marina). It is also myth that it cleans the tank. It just delays the symptoms.
* A larger Raycor is an excellent idea. A separate polishing system is generally overkill, since the engine has a small amount of spill back anyway (I presume you have a double fuel line system). I have installed them on MANY engines and boilers; they don't solve everything, but they help and should be original equipment on all boats.

This post (http://sail-delmarva.blogspot.com/p/die ... cides.html) is from a large article I did for Practical Sailor.

* Yes, a tank can be cleaned without pulling it or having a big opening, depending on the number of baffles. A power washer and a shop vac (DIESEL FUEL ONLY--NOT GASOLINE) will make short work of it.
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http://sail-delmarva.blogspot.com/2017/ ... store.html
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Re: "Buggy" Fuel Problem

Postby philiprmcgovern » Tue Jul 05, 2011 6:43 pm

Thinwater:

Thanks for your very helpful post about fuel tank problems. You have convinced me to add a large additional secondary (tertiary?) filter to Sunshine's engines (diesels) if I can figure out a good location for them. It's pretty crowded in the starboard locker now, but I'll figure something out. I'm open to any suggestions, though. The little Racors that the factory supplied just don't seem to last very long and they are a little pricey to replace. Thrifty guy that I am, I usually use NAPA (Bix brand?) elements but even they aren't cheap.

Do you happen to know how many, if any, baffles there are on the 36 LRC? Until I get around to the shopvac and power wash method you mentioned, I might just stick the little bilge pump in the sender access hole and see how much goop and water I can pump out from the bottom of the tank. Does this make sense to you?

My problems in the past seem to be with water rather than with snot or waxy stuff and, since water sinks, why not just pump it out? If there are baffles in the way, that may not be such a great idea. Yes, I do try to keep the tank full to minimize condensation, but the water still seems to sneak in somehow.

Thanks again,

Phil McGovern
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Re: "Buggy" Fuel Problem

Postby SecondWind » Wed Jul 06, 2011 7:27 am

There are no baffles in the tank. The best way to clean it is to remove all of the fuel and remove the tank from the boat. It is not difficult to remove. Clean the tank thoroughly by what ever method you choose (soap and water would be ok). Make sure that the rinse water is clear of any matter before you finish. Finish the job by sloshing a gallon of methanol to remove water and then a gallon Acetone to dry it out. (You will need to manually turn the tank around and over.) Let it dry out completely before re-installing. If you fill at a marina with Valvtech brand fuels, they are already stabilized and have algae inhibitors, otherwise just add the recommended amount of Bio-bor each time you fill up. Try to keep the tank full to inhibit water condensation.
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Re: "Buggy" Fuel Problem

Postby philiprmcgovern » Wed Jul 06, 2011 6:29 pm

Thanks, Terry. I'll put your good advice into practice when we get back aboard.

Phil
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Re: "Buggy" Fuel Problem

Postby maxicrom » Mon Jul 18, 2011 1:13 pm

II the Max has a single Racor 100 series filter in the Port locker closest to where the fuel line goes to the motor in the hull, our Yanmar diesel is set under a pilot berth in the port hull - about the same location as the head in the STBD hull. There is plenty of room in the compartment, my solution is to relocate the 100 series Racor to the engine compartment and add the new 200 series filter where the 100 was. Both Racors have built in manual fuel pumps so priming should not be difficult. With the two Racors 10 micron (200 series) and a 2 micron (100 series) all the crud should be trapped before getting to the internal Yanmar filters which are both a pain to change and difficult to access since they are low and close to the motor. The Yanmar filters are tiny compared to the Racors and don't have built in water separators.

I'm hoping that with the Racors will trap the big stuff long enough that I can burn through enough fuel to mange the remaining with jerry cans and jugs, then properly clean the out the tank. The 200 series Racor was about $95.00 with another $20.00 in fittings and hose. Just haven't haven't really had time to work on it lately...

FYI: Early this morning one of the marinas on the Anacostia river in DC had a fire and 4 boats were badly burned - it always worries me to have a boat that is not running.
Mike & Linda
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Re: "Buggy" Fuel Problem

Postby maxicrom » Tue Sep 27, 2011 1:52 pm

Well finally got around to getting our engine running...

When I opened the first filter in line - it was full of black goo - luckily the blockage was ahead of the Yanmar filters. To be safe I rigged up a 3 gal outboard tank (with fresh fuel) to the existing system with new filters of course. So now we can at least move our boat if needed. The next step will be to pump out the remaining diesel 5 gallons at a time then pull the tank over the winter and give it a good cleaning.

I've been told that I can mix the buggy fuel with our fuel oil and use it for heat in our boiler system (I'll filter it with cheese cloth first to get any large particles out). Hate to just throw it away but don't want to clog the furnace filters either.

Always something...
Mike & Linda
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Re: "Buggy" Fuel Problem

Postby holomoku » Tue Sep 27, 2011 7:05 pm

Umm....I've read through this thread kinda casually but, a couple things caught my attention.

Blowing out a fuel tank with a shop vac after rinsing with alcohol and carb cleaner????????
Reminds me of a story years ago of a guy SHOP VACing up gasoline after a spill in his garage...BOOOOOM!!!
True, blowing is different than sucking, but a sparking electric motor near flamable fumes inside a closed system is dangerous....be careful!

Number 2: How is putting bad fuel in your home furnace better than putting it in your boat motor? (Rhetorical...I wouldn't do it...throw the bad crap out)

Maybe OK in the tiki torches on your deck

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Re: "Buggy" Fuel Problem

Postby philiprmcgovern » Tue Sep 27, 2011 7:13 pm

Mike:

Thanks for the update. I have been meaning to set up a "get home" tank similar to the three gallon tank you described on each engine. It could be very useful when the Racors get clogged and the sea conditions are too rough to make changing them them out practical. The extra tanks would "T" into the fuel line just after the Racor. If the fuel in the small tank is clean, the primary filter should be able to handle it. Like you, I don't feel comfortable with a boat that can't be moved. (Yes, I know it's a sail boat, but still....)

I'm curious about how you plan to clean your tank. The only "access" hole on the top my tank is the 2" or so diameter hole for the (non-functioning) sending unit to the fuel gauge threads into. Do you have a larger access hole on yours? I am reluctant to cut another hole in the tank, but that might be what I'll end up doing. I have been told that there are no baffles in the tank, so that would be a plus.

Since most of the crud is supposed to be on the bottom of the tank, I have been tempted to just stick a hand operated bilge pump though the hole and pump away and see what comes out. It might get at least some of the bad stuff out.

Keep us posted. Best wishes.

Phil McGovern
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Re: "Buggy" Fuel Problem

Postby SecondWind » Wed Sep 28, 2011 7:32 am

The best way to clean the tank is to remove it from the boat. It is not heavy and there are not many fittings and screws to remove. After it is out, scrub it with Mineral Spirits, plug the openings and slosh it around good, repeat as necessary until all of the gunk is gone, and final rinse with Acetone or MEK. It is a good time to make sure the vent hose does not have a dip in it and to replace some of those old fuel lines and hose clamps. The get home tank idea is a great additional idea.
Terry Green

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Re: "Buggy" Fuel Problem

Postby maxicrom » Fri Jun 29, 2012 10:55 am

Update,

Looks like the issue forced itself upon us... a few weeks ago we noticed a small sheen "near" our boat. Unfortunately for us it coincided with a large fuel oil leak at the nearby fish market (a crab steamer barge collapsed) - and all assumed the sheen was a remnent of the larger spill. After about a week of the recurring sheen "near" II the Max I figure it could be from us - normally any diesel leak will leave a significant odor - and our cockpit area was normal. Just sharing for others. I had a neighbor come over and "bounce" in the cockpit while I watched under the boat, sure enough after about a minute a few drops of diesel came out the drain hole.

When I lifted the cockpit floor the area was relatively dry, except for slight dampness if I slid a diaper under the tank. The tank was almost full, about a 1/4" from the top. All we can figure is that the tank weaped when either someone walked on the deck or the heat expanded the fuel. Our neighbro does marine work and he brought his portable fuel polisher over. We ran our fuel through the polisher and into my other neighbors boat (an Ocean 36 Sportfish), he has twin Detroit's and was very happy for a free 50+ gal's of diesel (we thought the tank was 30 G. but the tag say's 55). I was really surprised watching the fuel go through the dual Racor separators it did not appear buggy. PDQ's drains make it easy for containment, we put an oil dam across the bows and sterns and all was well.

Tank is empty with only the hoses are holding it - will try to take some pix when I pull it tomorrow morning. If anyone knows a good source for tank repair in the Annapolis area let me know. The aluminum looks to be in very good condition. The surprising thing was when I called the local authorities to report the spill and status, they asked if it was contained - we told them yes and gave them the details. They took the info over the phone and said thanks, that was it.

Question for Jame's: Our floor for the most part is above the tank but I think if there is weight on the floor and the tank is expanded there may be some some contact. I'm thinking about having some some support channels added to the top of the tank, or maybe adding a shim to tne bottom of the floor pan to raise it a 1/4", or both. Any suggestions? I don't think that would affect the aft drains.
Mike & Linda
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