Fuel tank serviced
- Thread starter Billylll
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Capt. Bill1
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Pulling a fuel sample is one thing, getting the baffled fuel tank in a boat truly clean by only going in through the fill tube or one small access plate is completely different.
Until you open one up and see how well they can be chambered off you might believe simple stirring up of the fuel is enough to clean the tank.
The whole point of baffling is to keep the fuel from moving around in the tank even in very violent seas. So shooting fuel under pressure down into the tank into one does not necessarily get the fuel moving around in any other part of the tank.
So what ever peace of mind tank cleaning may bring some one, if it's not or can not be done correctly, then it's a false one at best.
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It s a fine line between prettier maintenance and "if it ain't broken don't fix it" but in this case I woudl probably run the boat first before.
How big is the tank, how much fuel is in there and how old is the fuel?
Assuming the fuel hasn't been sitting there for years and the boat has been used, I d rather spend the money on switching to dual racors with a vac gauge then doing a fuel polish which may or may not really clean it all depending on the baffles set up. With dual racors and a vac gauge you can see how your filter is doing and if it clogs, all it take is a flip of a valve to keep going.
While fuel filters may not be as cool as other things.... That set up is a must have in my opinion
How big is the tank, how much fuel is in there and how old is the fuel?
Assuming the fuel hasn't been sitting there for years and the boat has been used, I d rather spend the money on switching to dual racors with a vac gauge then doing a fuel polish which may or may not really clean it all depending on the baffles set up. With dual racors and a vac gauge you can see how your filter is doing and if it clogs, all it take is a flip of a valve to keep going.
While fuel filters may not be as cool as other things.... That set up is a must have in my opinion
250 gallons total tank size. The boat was not run other than to start the engines at launch and to winterize. There is about 80 gallons of 2 to 3 year old fuel in the tank. The fuel has been treated with Algae-X.
I'm going to have the fuel polished, tested, the tank cleaned and pressure tested.
Bill
Capt. Bill1
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I'd invest in the water probes and alarms for the Racors before vacuum gauges. Those small diesels flow so little fuel that they don't pull much vacuum even when the filters start to clog. I've seen dirty filters on a number of engines like those where the vacuum gauge was indicating no need to change the filters.
Filter elements are cheap. Get 900 series Racors so you have lots of surface area and change them every 100 hours or so. Unless your fuel is really dirty you should be fine. I'd even consider using the 2 micron elements with as big as practical fuel lines to them to catch any contaminates well before they could get to the engines. I used 2 micron elements for my 120 hp Lehmans for years. As well as in lots of other low HP diesel powered boats with no problems. And the elements lasted an easy 100+ hours if the fuel was reasonably clean. The trick is to stay away from using the small Racor filters. As I mentioned earlier, you want to use an element with lots of surface area so it can hold lot of contaminates without causing a restriction.
Filter elements are cheap. Get 900 series Racors so you have lots of surface area and change them every 100 hours or so. Unless your fuel is really dirty you should be fine. I'd even consider using the 2 micron elements with as big as practical fuel lines to them to catch any contaminates well before they could get to the engines. I used 2 micron elements for my 120 hp Lehmans for years. As well as in lots of other low HP diesel powered boats with no problems. And the elements lasted an easy 100+ hours if the fuel was reasonably clean. The trick is to stay away from using the small Racor filters. As I mentioned earlier, you want to use an element with lots of surface area so it can hold lot of contaminates without causing a restriction.
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As someone who has had bad fuel do to sitting before I bought my boat I say money well spent! I had problems I was fouling filters in s few hours at the end of my first season. In the spring of my second year I borrowed a fuel polisher and cleaned both tanks I have not had a problem since. I forget what I was quoted to have someone do it for me but it was a lot of money they billed by the total gallons the tanks could hold regardless of what was in the tanks. If I recall it was about the same price of a the fuel for a full tank at the time I hold 432 gallons hence the reason I did it myself.
quote:
Originally posted by Sandy
In that example it sounds like the pickup was too low!
I'm not sure if the pickup was lower it would have prevented 13" of sludge and possibly some of the water. Since it drew it's level higher it never pulled fuel from the lower 13" of the tank. I might be wrong using this logic?
Bill
There is no doubt that bigger filters reduce the chance of clogging and need for changing however Racors centrifuge fuel as a part of their design so using a too big filter may reduce that ability, I don't know for sure. Check the makers web site. I installed drain cocks on the bottom of my racors but never had to use them. Tony Athens recommends spin on filters. I don't like them because I really want that clear bowl to inspect the fuel. Tony also recommends installing outboard fuel bulb pumps to make priming the fuel system easier. I would do that if I were redesigning my system. He has two designs posted on his site.
Bill, Congratulations!!!
The trawler purchase will take your boating in the direction you've wanted for a long time.
Glad you'll do the extra tank maintenance. This is an area where I have no specific expertise. Still, as I filter through everything everybody said, the idea of just possibly smoking out an issue that you can correct while you're still outfitting looms large.
Trawlers may not be the hottest topic here, but that's about to change. You and your projects are Always HOT!
The trawler purchase will take your boating in the direction you've wanted for a long time.
Glad you'll do the extra tank maintenance. This is an area where I have no specific expertise. Still, as I filter through everything everybody said, the idea of just possibly smoking out an issue that you can correct while you're still outfitting looms large.
Trawlers may not be the hottest topic here, but that's about to change. You and your projects are Always HOT!
Capt. Bill1
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The flow rate is so low in those engines, and in fact on many engines, that there is little or no centrifugal action in even the small Racors. Racor will tell you that most of the water removal takes place at the element.
I would stay away from the spin on ones as well. For the reason you state and the fact that the top element access ones are easier, cleaner and faster to change. I like the clear bowls too.
The bulbs are a good idea but I'd go with electric fuel pumps myself.
Capt. Bill what type of electric fuel pumps and how would they be plumbed in? I guess the squeeze bulbs are a good idea from a reliability standpoint. But if you haven't got enough 12VDC to turn over a diesel starter power to the primer pumps wouldn't be an issue?
Bill
Bill: the loss of fuel and battery at the same time would be very unusual. Diesels in proper shape don't need a lot of cranking to get fuel to the injectors unless there is a leak down.
Extra cranking may be needed in very cold weather to warm up the cylinders but good diesels light off with a few compressions. Diesel is an elegant technology compared to gas.
electric pumps or bulbs would be plumbed in the same way IMO. Either as a parallel system with valves or in line. In line while much simpler is more difficult with big engines because of the large fuel flow. you don't want the pump to restrict flow but only a small pump is required to fill the filters. In your case the bulbs certainly would not restrict flow.
As a rule of thumb for calculating filters, line size, pumps, bulbs etc. since diesels recirculate fuel, I assume yours do, the input line needs about three times the max engine consumption.
I wonder if your engines have a hand crank and compression release valves. Old small diesels could be started with very weal batteries or even a hand crank if you were feeling your oats.
Extra cranking may be needed in very cold weather to warm up the cylinders but good diesels light off with a few compressions. Diesel is an elegant technology compared to gas.
electric pumps or bulbs would be plumbed in the same way IMO. Either as a parallel system with valves or in line. In line while much simpler is more difficult with big engines because of the large fuel flow. you don't want the pump to restrict flow but only a small pump is required to fill the filters. In your case the bulbs certainly would not restrict flow.
As a rule of thumb for calculating filters, line size, pumps, bulbs etc. since diesels recirculate fuel, I assume yours do, the input line needs about three times the max engine consumption.
I wonder if your engines have a hand crank and compression release valves. Old small diesels could be started with very weal batteries or even a hand crank if you were feeling your oats.
Perhaps the smaller 2 cylinder diesels might have hand cranks. I doubt the Perkins 4-236 do. I know 85 hp isn't much but I can't imagine trying to hand start even a gasoline motor let alone a diesel motor that size.
Bill
You are probably right. Look at the front of the crank damper. That's what the compression relief valves were for.
I would add the bulbs just simpler. Cut the line push in proper size bulb for the line add clamps and your are done.
I would add the bulbs just simpler. Cut the line push in proper size bulb for the line add clamps and your are done.