Has anyone cleaned out their fuel tanks? Are there baffles? Looks to be a messy job, but I often have issues with clogged filters at inappropriate times; usually with guests aboard or when I need the engine for docking in tight areas. I have thought about adding another filter system that I could switch to when one becomes clogged. I know that Black Pearl had plastic tanks made to fit inside the old tanks and may consider this option once I get things apart.
Fuel Tanks
- Thread starter Whit
- Start date
The original feul tank on my Zephyr is this impressive polished or stainless steel body above the keel, and held 30-40 gallons of gasoline. When I bought brabant ( now foolish things ) in 2005 niether the surveyor, the engine mechanic, the restoration shipwright, or I could determine whether the tank had sediment, how to clean the tank, whether the tank was free of leeks and would remain so, or whether the tank would work for
gas but not diesel. The tank could not be removed and inspected because it was under ribs that were set in the fiberglass
and was virtually an integral part of the hull. When we got a new diesel engine, we installed plastic tanks port and starboard under the cockpit benches and new fuel lines, and they have been 100% trouble free.
The handsome original tank is enjoying retirement under the cabin sole.
gas but not diesel. The tank could not be removed and inspected because it was under ribs that were set in the fiberglass
and was virtually an integral part of the hull. When we got a new diesel engine, we installed plastic tanks port and starboard under the cockpit benches and new fuel lines, and they have been 100% trouble free.
The handsome original tank is enjoying retirement under the cabin sole.
Usually there is a way to get in the tank through the tank level sender or another plug/cover. My tanks are small enough that with a hand pump or drill pump you could clean them up. Most of the sludge is from an algae that grows on the interface of the diesel and water in the bottom of the tank and forms what I fondly call whale boogers. On our tugs it is a real problem. I actually spent some time in one tank this week on our tug hauled out at D N Kelley's in New Bedford- but I climbed in with a pressure washer & scrub brush!
There are additives to kill this stuff and emulsify the sludge but beware- it all becomes suspended and you really have a field day with the filters. Once treated and cleaned up, a little of this will maintain the tanks to prevent future problems. We use biobor but there are other ones as well. Talk to your yard. They might have a fuel polisher or know a company that does it. They siumply treat and then filter your fuel through their own filter system. Never done this as it's too expensive for the amount of fuel we deal with on the tugs but I think it works.
In a similar vein what about this new ultra low diesel- I've heard it's not good for injectors because there is not the lubricity (?) there used to be and we should be adding a treatment for this. I also heard most yards will do this prior to the sale but how do you know?
There are additives to kill this stuff and emulsify the sludge but beware- it all becomes suspended and you really have a field day with the filters. Once treated and cleaned up, a little of this will maintain the tanks to prevent future problems. We use biobor but there are other ones as well. Talk to your yard. They might have a fuel polisher or know a company that does it. They siumply treat and then filter your fuel through their own filter system. Never done this as it's too expensive for the amount of fuel we deal with on the tugs but I think it works.
In a similar vein what about this new ultra low diesel- I've heard it's not good for injectors because there is not the lubricity (?) there used to be and we should be adding a treatment for this. I also heard most yards will do this prior to the sale but how do you know?
I am planning to open up the fuel tanks this spring and replace the steel covers, which are badly rusted - they have lost a noticeable fraction of their thickness and flake off thick pieces. The tanks were opened and cleaned about 20 years ago, but I was not involved with the boat then. Photos showed a lot of black sludge, and I have faithfully used a biocide since then. The tank level sender allows a look inside, and I can see a shiny bronze keel bolt. I use this port to pump out the bottom gallon or two of fuel out every spring before commissioning - at least I pump until I get a gallon of so of decent looking diesel. Water with a lot of whitish crud comes first. There is usually a fair amount of heavy rusty steel bit that clogs the pump. The port is too small to reach into though. Fishing through it however reveals a baffle forward. The steel cover is in two pieces, so it appears that there are two chambers on each side, with baffles with holes in them (I assume to prevent sloshing). The covers are held on by nuts that screw onto studs. I'm nervous about turning the studs loose when removing the nuts, so am prepared to split the nuts loose, and then chasing the threads clean.
I plan to replace the covers with stainless. Someone has said that the weight of the covers was a design feature, and I suspect they provide stiffness to the hull. I will also put in ports large enough for cleaning out the interior occasionally. So far the integral tanks have worked well, so I see no need to put in other tanks. There was at one time a slight weeping of diesel that covered about a square foot of the keel; that was when the boat was on stands, and I suspect that the weight of the boat on the keel allowed a keel bolt to be unloaded a bit so that a little fuel could get out.
I have two Racor 500 filters (10 micron and 2 micron) in series with an electric fuel pump in-between (the second filter was a eBay bargain). The pump helps bleeding (although I haven't had to bleed since installing it!). I run the pump before starting to get pressure in the fuel line and to purge any air back to the tank through the fuel return line. After the engine warms up a bit I turn it off - don't want diesel accidentally sprayed around. I have also used a vacuum gauge that replaced the Tee handle on the filter that was useful for monitoring the filter. You can also plumb a gauge in and mount it on the engine control panel, but that gives a potential place for leaking air into the fuel line.
I'll let you know what I discover when I take the lid off - probably in a month or so.
I plan to replace the covers with stainless. Someone has said that the weight of the covers was a design feature, and I suspect they provide stiffness to the hull. I will also put in ports large enough for cleaning out the interior occasionally. So far the integral tanks have worked well, so I see no need to put in other tanks. There was at one time a slight weeping of diesel that covered about a square foot of the keel; that was when the boat was on stands, and I suspect that the weight of the boat on the keel allowed a keel bolt to be unloaded a bit so that a little fuel could get out.
I have two Racor 500 filters (10 micron and 2 micron) in series with an electric fuel pump in-between (the second filter was a eBay bargain). The pump helps bleeding (although I haven't had to bleed since installing it!). I run the pump before starting to get pressure in the fuel line and to purge any air back to the tank through the fuel return line. After the engine warms up a bit I turn it off - don't want diesel accidentally sprayed around. I have also used a vacuum gauge that replaced the Tee handle on the filter that was useful for monitoring the filter. You can also plumb a gauge in and mount it on the engine control panel, but that gives a potential place for leaking air into the fuel line.
I'll let you know what I discover when I take the lid off - probably in a month or so.
The LeComte NE 38s have the same sort of bolted tanktops and therefore the same problems. One important difference is that the later ones have fiberglass tops, but have the same rusting steel bolts.
You'll find lots of discussion on the LeComte Owners site http://www.lecomteowners.com/ and on a French NE 38 owners' site http://beckerlaurent.free.fr/ucap/philippe/p1.htm#prem , in French, you'll see good pictures showing replacing his tank tops in stainless as well as how he replaced his bolts.
I concluded that my NE 38 had enough webs and fixed portions of tanktop spanning the gaps across the tank that the tops were not very structural. Your Challengers have great long tops and I don't remember the webs.
On the LeComte owners' site, the discussion includes how to replace the bolts; there are at least three alternatives, none easy.
You'll find lots of discussion on the LeComte Owners site http://www.lecomteowners.com/ and on a French NE 38 owners' site http://beckerlaurent.free.fr/ucap/philippe/p1.htm#prem , in French, you'll see good pictures showing replacing his tank tops in stainless as well as how he replaced his bolts.
I concluded that my NE 38 had enough webs and fixed portions of tanktop spanning the gaps across the tank that the tops were not very structural. Your Challengers have great long tops and I don't remember the webs.
On the LeComte owners' site, the discussion includes how to replace the bolts; there are at least three alternatives, none easy.