34DC fuel tank replacement. Tanks?

[88FuHwa]

I am not sure whether we have a similar situation but my starboard tank was leaking profusely when I filled it up once. I had to have the bilge pumped out and paid a fortune because the diesel was then considered hazardous waste. Never mind that the boat yard sold it anyway from the "hazardous waste" tank to others.
Once the tank was empty, I opened it up through the inspection plate and could not find anything wrong at the bottom seams. I have since been filling it up again to about one quarter of capacity. I have left it the diesel fuel there and it is not being used other than for balancing the boat. No more leaks so I suspect the leak is higher up and I am not going to fix it. So, technically it is not serviceable. The port tank is holding the 175 gallons and has been no problem so far. At 2 gallons per hour I can go long way on just one tank.

 

[CharlieO.]

I have one tank that seeps just little bit, looks like someone applied splash zone to the outside in one spot, the other tank doesn't leak currently but the top of that one is very rusty. There is only about 3 inches of fuel in each tank right now. I did not want to risk a fuel spill into my bilge like you had...doesn't sound like fun.
I look forward to getting it done.

Thanks

 

[Nick F]

Charlie - what size fitting will you have at the inlet to the Racor?

5/8" hose will certainly work, but it is pretty chunky hose and routing may be not very tidy because it won't curve as tightly as a smaller hose.

If you were to use a size which matches (the almost certainly smaller) inlet size at the Racor, you have the issue of adapting the size at the tank top - probably requiring extra connections (possible future leak points).

Its a trade-off. Within reason, I like to minimise the number of connections.

Regards,
Nick

 

[Nick F]

Quote: but my starboard tank was leaking profusely when I filled it up once unquote

Dirk,
If you are curious as to the leak location you could put a small amount of air pressure in your leaking tank and look for the leak. It is very likely on the top of the tank - due to deck leaking and water sitting on the tank top.

You could pressure the tank using a hair dryer (on cold!) or a shop vac (more aggressive - be very careful) or a dinghy pump. I would leave the vent line open to limit pressure build up.

Regards,
Nick

 

[CharlieO.]

Thanks Nick, I was hoping I could either change the inlet fitting on the Racor to 5/8 or possibly I could just replace the whole pick up tube assembly to the size I want. Just didn't want to create any problems going from the larger pick up to the smaller feed.

Still need to get back in there to verify all my fuel line diameters. Weather has been not cooperative for me to finish up my bilge repair just yet, so may start taking the sawzall to the port tank on Friday.

 

[CharlieO.]

Port tank, this is the tank that had a slight leak.
Had to remove the holding tank to get to the fuel valves.