Fuel Tank question

iSailor · Jul 26, 2013

Alansails said:
After our trip on our 310, which had been flat sailed on an inland lake-engine had only 130 hrs on a 11 year old boat. We got her on Lake Erie and stirred her up ALOT. When we got her she also had 1/2 tank of diesel and we changed the filters,oil and impellar. We filled her up and put additive in-Biobor jf -recommended by practical sailer along with fuel that has Valvetect in. we used some fuel than topped off the tank before going on vacation. we came back algae had blocked the fuel filter so we had to be towed the last 5 miles back to the dock. We had the filters changed again and the mechanic stated that he would recommend we run the rest of the fuel out than fill up again and not put additives in as there are enough now. I thought about fuel polishing and the mechanic stated that he would have to find out how many baffles there are in the tank and drill many holes to be able to get all the GUNK OUT!. I am OK with polishing the fuel but hole drilling? Does anyone know about how many baffles there are and how removable is the tank? Any other thoughts are appreciated... The fuel line to the filter is also on the outboard side making it a task to remove the filter from the wall and than change the filter and put it back on the wall. Has anyone changed the fuel line to the inboard side of the filter? this would make it easier to change without taking it off the wall. Thanks for your input.

I am having this issue as well. Just pumped 17 gallons (hand pump) out of the tank, changed filters and fuel pump. I was told that you also need a "dispersant" to breakdown the dead algae in addition to the anti-algae, which would stop the growth.

iSailor · Jul 26, 2013

Alansails said:
Thanks for your reply, Did you just empty the tank and dispose of the fuel? what kind of pump did you use?

used a transfer pump (harbor freight / tractor supply $15) and hooked it up AFTER the racor filter. That way it is filtered prior to going in the jugs (I had many 5 gallon fuel jugs from my car racing days).The hose from the transfer pump was the correct size to connect to the racor outlet. I am going to then treat that fuel and use it in my tractor and maybe truck.

JK_Boston_Catalina310 · Jul 26, 2013

I haven't been into our tank in much detail, but I think there is only one baffle. Here is the Catalina Direct link for a replacement tank: http://www.catalinadirect.com/index.cfm?fuseaction=product.display&product_ID=2947. They recommend installing two inspection ports to allow for cleaning.

A friend had this issue with a Catalina 30 he recently purchased. We rigged a fuel polisher with an electric lift pump and two filters from the auto shop (less than $100). We then spent an entire day polishing his fuel by pumping the oil out of the tank, through the filters and then back to the tank. By the end the fuel looked very clean and he hasn't had the clogging issue since. We changed out the filters twice during the process.

Long Story · Jul 26, 2013

Interesting question if it ever came up. How would you remove the tank from our C-310's? I have questioned how to get the holding tank out of the boat also?

JK_Boston_Catalina310 · Jul 26, 2013

Long Story said:
Interesting question if it ever came up. How would you remove the tank from our C-310's? I have questioned how to get the holding tank out of the boat also?

I believe someone else already removed the fuel tank because it has a spot rusted through. I think if you search the archives you would find it.

The holding tank, now how is that wood structure around held together? I think it might just be screws but need to get back there again.

JK_Boston_Catalina310 · Jul 26, 2013

I don't think it will work. We had to use the flow of diesel to get the sediment disturbed and moving. Otherwise it will just sit on the bottom and when you fill up again it will be disturbed and the whole problem will happen again. We also hooked up a small tube on the influent side and put it through the hole for the gauge sender unit and moved it around to try to get stuff up.

Witzend · Jul 27, 2013

No Baffle's in mine, monster to get out, must remove the fiberglass wall covering the holding tank, then because it is flexible, partially collapse the wall of the holding tank with the corner of the tank as it rotates around the rudder post. It took a come-along to get it out. No way you're getting it back in, must cut the corner of the tank off and have it re-welded, but that will give you nice access to thoroughly clean. Look for crevice corroding, especially on the front lower corner.
Not sure if it would come out via the hot water heater side when removed.
Good luck!
http://forums.catalina.sailboatowners.com/showthread.php?t=145642

Tom J · Jul 30, 2013

I had my fuel tank removed back in 2006, shortly after we bought the boat. A pinhole leak in a welded seam was allowing fuel to leak into the bilge. The yard crew tried sliding the tank out through the access door, but that didn't work. They had to remove the access panel on the aft bulkhead, then remove the water heater, and finally slide the tank out.
As far as polishing the fuel goes, I had a guy with a mobile fuel polisher come down to the boat last summer. He removed the fuel level sending unit and inserted two hoses into the tank, one to suck the fuel out, the other to spray the fuel back in. He moved the input hose around to stir up any sludge. He didn't seem to have any issues with baffles. His computer determined when the fuel was clean and free of any water. It took about five cycles to clean the fuel. Hope this helps.

oldguy · Jul 31, 2013

Alansails said:
After our trip on our 310, which had been flat sailed on an inland lake-engine had only 130 hrs on a 11 year old boat. We got her on Lake Erie and stirred her up ALOT. When we got her she also had 1/2 tank of diesel and we changed the filters,oil and impellar. We filled her up and put additive in-Biobor jf -recommended by practical sailer along with fuel that has Valvetect in. we used some fuel than topped off the tank before going on vacation. we came back algae had blocked the fuel filter so we had to be towed the last 5 miles back to the dock. We had the filters changed again and the mechanic stated that he would recommend we run the rest of the fuel out than fill up again and not put additives in as there are enough now. I thought about fuel polishing and the mechanic stated that he would have to find out how many baffles there are in the tank and drill many holes to be able to get all the GUNK OUT!. I am OK with polishing the fuel but hole drilling? Does anyone know about how many baffles there are and how removable is the tank? Any other thoughts are appreciated... The fuel line to the filter is also on the outboard side making it a task to remove the filter from the wall and than change the filter and put it back on the wall. Has anyone changed the fuel line to the inboard side of the filter? this would make it easier to change without taking it off the wall. Thanks for your input.

I had fuel gunk clog the filter on the bulkhead a few years ago. We tried just about everything else (clean injectors, new fuel lift pump, etc.) until isolated it to a small orifice in the bulkhead fuel filter. I shut the fuel at the tank, removed both fuel lines from the filter and cleaned it on the bench. No problems since then.

FastOlson · Jul 31, 2013

Probably Not what you want to hear...
but installing some clean-out ports in the top, between each/any baffle is the real solution.
No, our boat did not come with these, but I refurbed the whole fuel system and had this work done.
From then on you can open 'em up and wipe the tank clean any time.
Here is one available solution:
http://www.seabuilt.com/6plates.php

As for "cost", add up multiple boxes of new filters, towing costs if needed, and cost of fuel polishing. In the long run, it's cheaper to do it right, IMHO.
:cry:

iSailor · Aug 8, 2013

Alansails said:
Here Are the results :
We had our fuel polished on tuesday and we were very impressed. They were on time, brought an amazing set of systems to not only suck the fuel out and run it through filters and show me every step of the way what was going on but also show me what they had collected from the bottom of the tank including.....yes that foil cover that you take off the top of the plastic bottle before you dump it in the tank AND you remember the chain that used to attach your filler cap to the boat? Yes that was also sucked out of the bottom of the tank! The fuel was so bad that they removed all of it and replaced it with 10 gallons of new treated diesel fuel and ran that through filters at the two micron level-size of a hair follicle. Using pressure, they fuel power washed the inside of our tank removing the dead algae, water and other things found in the bottom and along the sides. It was very impressive and amazing the job they did and were very professional. They laid moving blankets on our boat to protect where they walked and showed up wearing white polo shirts and never got them dirty. I am giving you the brief version but they took three hours to do all the steps,they also gave us a product called desl-shok that they had used to treat the fuel and encouraged us to continue to use it. They also supplied follow-up instructions as to what to do after, including changing the filter and RUNNING the engine,not just at idle!
> The fuel bowl is now rose colored instead of BLACK. They said the fuel was like asphalt.
Btw they came to the marina and we did not have to move the boat, which was good.. We are glad we made the decesion to do this. Money well spent especially considering their time and the filters plus the 10 gallons of treated diesel. She now runs like a top!

Now the important question...... Cost?

iSailor · Aug 9, 2013

Alansails said:
Given the time they were with me (almost 4 hours) filters used, new treated diesel (10 gallons) to replace what they pulled out of our tank, plus gave me a large bottle of desl-shok fuel treatment- cost $400. - piece of mind to my wife = PRICELESS.
I felt it was very good value

completely agree. If I continue to have fuel issues (due to crude on the bottom of tank), I will probably go this route as well.