Fuel Tank Baffles

[Taras]

Hi All,
My fuel tank guy has installed a couple of Inspection/Access Ports into my fuel tank for future cleaning.
He cut the center sections out of the 2 baffles to be able to get in a scrape and clean the bottom. The only section of the baffles removed was a square taken right out of the middle of the baffle.
My question is, is it a good idea to cover this new hole in the baffle? Should the baffle be plated shut so that it is complete?
He claims that the only purpose of the baffle is to create strength of the tank, not to stop or impede the sloshing of the fuel.
My concern is the weight of that much fuel sloshing fore and aft while I am in a head sea. With the cycling of the weigh of the fuel back and forth, I am worried that it may eventually bust a seam in the tank.
Does anyone have any thoughts out there?

Thank you!

 

[ben2go]

Without knowing the dimensions,it's hard to say if the baffle is for strength or slosh.The manufacture put them there for a reason,I would like to keep them intact.

 

[FF]

He claims that the only purpose of the baffle is to create strength of the tank, not to stop or impede the sloshing of the fuel.

He is wrong , unless the tank was created super light for a high performance boat.

For a cruiser , if there is a baffle its probably to stop the high pressure from surging on the tank ends.

SKEENS has simple rulles for tank size , vs baffles, if I remember correctly.

FF

 

[rwidman]

Without knowing the dimensions,it's hard to say if the baffle is for strength or slosh.The manufacture put them there for a reason,I would like to keep them intact.

If they've benn cut, it's going to be pretty impossible to keep them intact. If covers can be fabricated for the holes, that would reduce fuel movement but not restore the integrity as far as strength goes.

Ideally, fuel tanks would be designed with cleaning in mind. Apparently, they are not.

 

[rwidman]

The only section of the baffles removed was a square taken right out of the middle of the baffle.

If we think about the rules for running pipes or wiring through floor joists in a building, he did this the correct way as far as retaining the structural integrity.

As far as fuel sloshing or moving through the holes, only fuel in line with the holes will pass through the holes. Fuel below the holes will not move and fuel above or to either side of the holes will not move until the fuel in line with the holes has moved.

Considering it's a trawler and you won't be jumping up on plane from a dead stop, I think you'll be fine without any further modifications. Of course, it won't hurt to cover the holes if it make you feel better. You just have to make the patches removable but strong enough that they won't come loose and roll around the bottom of your tank.

 

[Taras]

Ron,
Your explaination makes the most sense so far.
Thank you everyone for your comments!
Any other thoughts are greatly appreciated.

Taras

 

[Tom.B]

If it helps, here is a picture of one of Skinny Dippin's baffles during our tank cleaning last month. There are two of these in each of the two 150-gallon tanks. This is stock, I assume. The bottom corners have small cutouts where the fuel passes thru.

 

[psneeld]

Ron,
Your explaination makes the most sense so far.
Thank you everyone for your comments!
Any other thoughts are greatly appreciated.

Taras

I would say Ben2go's comment makes the most sense...without the original design specs...any alteration is just a guess...

Even a pic would help us backyard mechanic types form an educated opinion.

FF- SKEENS???? Got any more info where I can get the info you were aluding to???