Fuel tank leaks and baffles

[kabyak]

I'm dealing with pin hole leaks in my 200 gal. bow fuel tank. It has an existing access panel in the top but is divided into quadrants by baffles inside. I cut three 6" holes for the other sections and purchased sealing plates for each. Tedious cleaning revealed areas of deep pitting, no surprise. I treated the cleaned bottom with Extend, a rust converter, and will apply a coat of Flamemaster's CS3204 sealant over that. I'm optomistic in that the tank seems structurally sound otherwise. Time wil tell.
I'm concerned for the (2) 250 gallon side tanks, each have an access port
in the side at the forward end. I'm curious if any other BW owners have looked inside their tanks for baffles? Adding side ports is more difficult given the fuel immersion.

 

[Comodave]

Almost certainly that they will have baffles in them. Maybe not, but any reputable tank manufacturer would put in baffles in tanks that big.

 

[CharlieO.]

I wouldn't be too concerned about adding inspection ports on the side of the tank given it already has one forward. I've seen the ports installed on the side in each baffled section.

I'd be interested in some follow up when you are done.

 

[Pete Meisinger]

Tell us a little bit more about the repair job. Where did you get the sealing plates? How did the job go? Got any pictures?

pete

 

[Comodave]

Tell us a little bit more about the repair job. Where did you get the sealing plates? How did the job go? Got any pictures?

pete

Seabuilt is a source. The SeaBuilt Access Plate System is a
one of a kind product that allows access
to your diesel, water and holding tanks.

I just googled it and came up with several companies that have ports. Seabuilt is one that several people have recommended in the past.

 

[CaptTom]

I'm also following your progress. No leaks so far but I suspect the day will come.

 

[kabyak]

Comodave: I'm sure there are baffles, I'm looking specifically for owners of Blue Waters that might have direct knowledge of placement.
I found the ports, intended only for top use, at fueltankparts.com (aka Boyd Welding). these are 8" OD and offered in AL and SS, I chose SS.
I'll post some photos when I get my sealant and plates.

 

[Tator]

Curious as to the location and possible cause of your leaks. I too have bow tanks. I've never noticed any sign of external corrosion and when I dip my tanks with a water i.d paste, I've never seen any sign of water in the tanks or general crud. As to the baffles, I can't answer that as I've never had them opened. On my saddle tanks I do have square inspection ports located about 3/4 of the way up on the sides. BTW my side tanks are 200gal. each and my bow tanks (2) are a total of 150gal. Good luck with your seal job.
Tator

 

[charles]

I installed inspection hatches on the sides of 4 of my 130 gal diesel tanks. Cut the holes and cut a larger piece of steel for the cover. Drilled and tapped the holes for the bolts. Used diesel proof material to make the gaskets. Worked great, still there when I sold the boat 10 plus years later. Had a welder weld the pin holes in each tank. I gassed freed them my self under his instruction.
Aside: on the day he was to weld I told him my procedure for gas freeing going even beyond his instructions. I asked him to check, he is a lifetime welder full time in the profession. He leaned over smelled the first tank and said OK. I demurred and questioned him! He pulled out his torch igniter stuck it in the tank and lit it!
He said, " I told you it was gas free."
True story.

 

[Comodave]

Charles,
In another thread someone was asking about covering teak decks. I posted that you did an article for PMM, back when it was worth reading, about the bedliner you sprayed on your teak decks. I spoke to you a couple of years later about it. Maybe you can add something to that thread about your experience with bedliner.

 

[syjos]

I've had the inspection plate off Sandpipers 250 gallon fuel tanks.

There are 3 baffles athwartship with large access holes in each tank.

 

[kabyak]

Fuel tank progress

There was interest in my progress on this tank. I've added photos to show various steps.
Top center shows interior as found. Two shots with darkened surface are after cleaning (scraping, Simple Green, and Acetone) and treatment with Extend, a rust converter. Bottom right after sealing w/ CS3204.
I plan to get a pint of CS3204 to touch up any small voids.
Each plate requires 18 holes, 2 countersunk to attach the ring from the topside, 16 to screw down the top plate and gasket. Some misalignment requires me to dress some on the holes before final attachment.

 

[Marco Flamingo]

When I did my tanks, there was some question as to where and how many baffles. Tapping on the side of the tank indicated two baffles, i.e., three compartments per 120 gallon tank. But once the layout is assumed, an exploratory hole is drilled. A piece of wire (clothes hanger) is bent at 90 degrees such that one can sweep the inside of the tank the distance of the radius of the bolt pattern of the chosen access port (I used Seabuilt). If you find that you misjudged the baffle location, it is easy to move the hole, check again, and use the new, correctly measured hole as the pilot hole. Chances are the first hole will be inside the diameter of the final access port hole. Might save a lot of grief.

 

[Tator]

Kabyak, were there baffles in your tanks? I can't tell by the photos.

Ttaor

 

[kabyak]

It's in quadrants, all but one interior shot is the forward right section, so you see a baffle on its left edge.