How to clean a baffled alum fuel tank?

[soggy]

My two diesel tanks (65 and 50 gal) are really dirty - we've drained and cleaned what we could reach but is there any way or product to clean the rest of the tanks? We really don't want to cut an access hole ...

TIA

[a64pilot]

You can hire a pro polisher, they can often use a pressure wand, like a pressure washer and get a lot of stuff stirred up and then pumped though a filter that way.

I wouldn’t put any kind of cleaner in the fuel myself as it may have other effects that are undesirable.
Hire the Pro, or ignore it. If you keep using the tank and always, always use a good biocide, it will eventually clean itself, or clean itself well enough so that you don’t have to change filters any more often that anyone else.
Our tank has no access and when I bought our boat, it had obviously sat for long periods and the tank was full of junk, but after about a year or so, I no longer have any filter issues, I change them yearly just cause I think you should.
Now that I have said that I’m going to clog a filter 10 ft off of the fuel dock I’m sure.

[JPA Cate]

Originally Posted by a64pilot

You can hire a pro polisher, they can often use a pressure wand, like a pressure washer and get a lot of stuff stirred up and then pumped though a filter that way.

I wouldn’t put any kind of cleaner in the fuel myself as it may have other effects that are undesirable.
Hire the Pro, or ignore it. If you keep using the tank and always, always use a good biocide, it will eventually clean itself, or clean itself well enough so that you don’t have to change filters any more often that anyone else.
Our tank has no access and when I bought our boat, it had obviously sat for long periods and the tank was full of junk, but after about a year or so, I no longer have any filter issues, I change them yearly just cause I think you should.
Now that I have said that I’m going to clog a filter 10 ft off of the fuel dock I’m sure.

Dang, but ain't life like that? Thanks for the chuckle, A64.

Ann

[hellosailor]

soggy-
For $20 you may be able to buy an inexpensive borescope (often mislabeled as an endoscope) online, typically with a 15' cable and wither USB connected or WiFi. That would probably give you at least a shot at getting an "eyeball" inside the tank, possibly at least past the first baffles to give you some idea of what's really in there.
Good way to peek into all sorts of obscure places.

[soggy]

Thanks for the ideas - I'm calling a pro in the morning. We actually had polymerization of some of the fuel in the bottom of the tank ~ I blows my mind that people (PO) pay money for other's to take care of their boat ... but an objective eye sees the crime it was to have paid those bills without having knowledgeable accountability. Ugh.

[Cpt Mark]

If your tanks are baffled, no access, the pro isn't going to be able to do much with the wand for the same reason you can't with a rag. You could just use your electric fuel pump (used for bleeding the engine) if you have one and bypass the engine. Just run it through the racor and back into the the return line. You'll clog filters and get all the junk you can in a matter of hours. Next time you go out and seriously beat into the waves etc. you may knock more stuff loose, no big deal.

[sailingchiro]

I removed tank and cut 6" inspection holes above each baffle. I couldn't believe all the crud that was missed with previous cleaning. Removed all the diesel and powerwashed the crud out. Covered with 8" AL plates with screws and sealed. All good now. No more clogging filters.

I will tell you, one thing I didn't do but should have is rebuild my racors. They were sucking air. The kits are around $40 and found several leaks in the bottom seal as well as the powder coating on top was leaking underneath the coating.

[Emouchet]

Me neither, I did not wanted to drill holes and add an access hole.


Eventually, because there was not other way around, with lots of dirt at the bottom of the tank (25 years without cleaning) and far too many jam filters, I dived in.


I purchased an access plate from Seabuilt - Access Plate Systems, a few jig-saw blades, and all was done within about 6 hours of work, including cleaning.


All in all, it cost me less than the $500 the pro wanted to charge me for tank filterring, and I doubt the pro would have been able to get what I was able to hand remove.


The best is that this is a one time expense, because now, it is really easy to open and inspect the tank.

[soggy]

Thanks Emouchet ~ The company is very confident they can clean the tanks. I have to get rid of the 50 gallons of fuel either way (it's three years old and fuzzy with growth.)

I'll keep you posted if the pro came through or not. A simple rag on a hanger should tell me if there is still crud after the cleaning ... I was originally quoted 625 to polish the fuel (no tank cleaning) but now it's 475 for tank cleaning and removing the fuel... I'm going to give it a go.

[a64pilot]

There will still be stuff there, it’s sort of like washing a car, you can pressure wash one, but unless you put a rag to it, there will still be a layer of dirt.
However they should get most of it.

[Singularity]

Originally Posted by Emouchet

Me neither, I did not wanted to drill holes and add an access hole.

Eventually, because there was not other way around, with lots of dirt at the bottom of the tank (25 years without cleaning) and far too many jam filters, I dived in.

I purchased an access plate from Seabuilt - Access Plate Systems, a few jig-saw blades, and all was done within about 6 hours of work, including cleaning.

All in all, it cost me less than the $500 the pro wanted to charge me for tank filterring, and I doubt the pro would have been able to get what I was able to hand remove.

The best is that this is a one time expense, because now, it is really easy to open and inspect the tank.

I'd really consider this approach, except maybe roll your own access plates if you have time. Aluminum maybe $10, nutplates a few bucks, bolts/gasket material a few more bucks, a dollar for rivets. Plus drill, jigsaw and hammer/hard surface to smash some rivets. Could be done with hand tools if you have a hand drill, hack saw, and patience.

To get a basic idea:
Tank end ribs & access plates » Joshua's RV-9A Project

On the cleaning the baffled tank part...another example from the little airplane world. Assuming one has at least one access port through which to push some (at least) semi-rigid hose/pipe...again depending on time/motivation/problem/cost...one could rig a re-circulating sprinkler system as shown in the follow thread on cleaning out tank sealant material from an aircraft fuel tank (bioslime is a cakewalk compared to tank sealant). With the sprinkler-recirculating system you rig it up and ~walk away...jiggle/reposition the nozzles every now and then until the effluent runs clean.

https://mooneyspace.com/topic/14636-...achine/page/5/


Addendum: If I was creating my own access plate I would not rivet the inner circular piece to the inside of the tank (as shown on the RV-9 site); I'd cut it in half (so as to be able to stick it in the tank as two "c" pieces). I'd use floating nutplates (if possible). Once the top plate was ready to be installed, thread some thin (safety) wire through pairs of nutplates in the "inside" ring pieces, +/- inner gasket, tank top, outside gasket...then bending the wire over so the inside ring pieces don't fall in. Place the top circle in place with one bolt engaged loosely in a nutplate, then swing the top plate over...using the safety wire to guide things...removing the safety wire as you go. Once all bolts engaged, then tighten oppositionally. With this type of access plate...upon removal of the top plate (for next inspection) at least one of the inner "C" pieces will fall into the tank, but you'd just fish it out. Hope that makes sense.

[thinwater]

Actually, real pros would slide a pineapple through the baffle hole and use high pressure water. It's a refinery thing. Pretend pros polish fuel.

[Dolphin460]

First, let me say I have no interest in the company Star Brite.

I have over 10 years experience with their products for cleaning my cats lines and tank. Before I found this product, I spent way too much money on things that did not work. Then someone told me about Star Tron. Having already spent a lot trying to stop my motors from stopping on their own, I decided to do some in-depth research. So, I called Star Brite. When I asked the receptionist that I wished to find out about their fuel cleaning products she put me on hold. I was expecting someone to come on and give me a five minute talk and to direct me to their webpage. To my complete surprise the person that answered was the scientist that was instrumental in acquiring the patent rights to Star Brite formula from the Japanese who invented the product. He talked to me for well over 30 minutes explaining how the product came about, how Star Brite acquired the rights, why it works so well, and how many trucks use their product world wide.

I would highly recommend before you do a polishing, which is just a fancy word for filtering, that you treat your tank and lines with 936 Star Tron Tank Cleaner, and then start using 931 Star Tron Enzyme Fuel Treatment - Super Concentrated Diesel Formula.

This has been working for me for nearly a decade. Good luck and happy sailing.

PS. there are copy cats on the market and believe me they are not the same formula, but they will claim they are.

[sailingchiro]

I had the AL from a previous bimini top job. Cut 8" circles with a hole saw. Cutting the 6" holes in the tank was more than loud. Recommend doing it outside the boat. Cost was less than $20 and I know it is clean.
The crud inside was like sand and black granules. Roughly about a quart of crud came out.
I asked a boat mechanic how they cleaned tanks, he had about 5 gallons of washers, nuts, and bolts. He would pour inside of tank and vibrate the tank for several hours. Then take a magnet and get everything out. Then flush the tank.
And yes, 64pilot, I used many rags to wipe water and rest of crud out.
I really hated clogging filters just when everything was really rough!

[Compass790]

If you can remove the tanks you could try petrol ( gasoline ) & agitation. Did that with ours ( but only 6 gallon tank) & it was unbelievable the amount of crud that came out. Tank appeared to be coated with a bitumen like substance that did get dissolved by the petrol.
Even a tree leaf came out of the tank WTF ??? Havent had any problems since then. P.O. had a deck filler cap with no o-ring on it so it had a lotta water in it.We always use a filter funnel when filling as It's surprising how much crud gets delivered with yr diesel from the pump