Boat listing, Fuel tanks don't equalize

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fullsail

Member
Joined
Sep 12, 2012
Messages
24
Location
USA
Vessel Name
Brass Ring
Hi. Anyone have this problem? I have a 36 Heritage sundeck with a single cummins. Fuel tanks are port and starboard. The boat lists to starboard. Most of the cabinetry, batteries, heads, are on starboard side. I put in 50 gallons on the Port side and it all flowed to the starboard tank. I am going to fill both tanks to see if that levels the boat. Anyone have any ideas as to why it lists? Thanks
 
Yep, you have too much weight in the starboard side!!! You have a cross-over line between the tanks. Look for a valve and close it to keep the fuel from crossing over into the other tank. Find out how your fuel returns to the tanks when the engine is running to determine how to adjust tankage while cruising. If you have a generator it will add to the equation.

Once the tanks are equalized you can begin to mess with trimming the boat with various weights. It doesn't take much ballast in the correct location to make a big difference.
 
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Our aft-cabin (under the bed) water tanks cause a HUGE list on Skinny Dippin'. Just bringing it up as a it-might-be-worth-a-check.
 
When adjusting your fuel manifold you must be certain that the fuel is being returned to the same tank it is being drawn from. Failure to ensure this can cost you big time in fuel spill fines.
 
I'm with Tom, with full water the boat lists slightly to starboard, not well thought out. And while I am plumbed with an crossover line on the fuel tanks, it appears to be clogged with 26 years of muck and they don't equalize. No real issue since I don't have a generator.
 
Tom B: what did you do about the water tanks under the aft bed? I might have compounded the problem when I filled the water tanks, then added 50 gals to port. I noticed the shower floor in the aft cabin head, starboard side that lists, had water under the wood grate. So, I'm hearing that I need to check the cross-over line and value, and then, what, keep the starboard aft cabin water tank low?
 
I left them alone? I am just pointing out that listing isn't always a single solution problem. Our stateroom berth sits at a 45-degree angle to the centerline. When we are low on water, Skinny Dippin' leans to port. When both tanks (there are two under the bed) are full, she will sit level-ish maybe just a touch to starboard. I have closed off one tank before to try and keep her level, but the water will get rancid if left in there too long.

All I am saying is for you to add the water tanks to your radar as a contributor to ballast listing. It took Bess and I a while to figure it all out too.
 
I actually have the same issue, listing to sb side. I'm suspecting that the reason lies within the water tanks in the aft cabin. So, I have two tanks and one fill up point, the tanks are connected with a hose that joins the tanks from the bottom.

Last I checked the hose is bent and could be the cause of unequal fill up. I only realised this after the boat was off the water so no testing posible. In the spring I will straigjten the hose and then do a fill up and take my time and see try to see if both tanks fill up. I' not even sure that there is a braether hose in the other tank.

If all else fails, I'll install a thru deck filling point to the other tank as well.
 
We have a simple y-connection too, but if you just let it keep filling until the tank vents stream water, both tanks will eventually fill to capacity.
 
Here is my experience with the same issue.

I have two tanks, port and starboard, with a crossover line. After a cruise, the boat listed to port, and wouldn't return to level. I filled both tanks, and it still listed to port. So, I added 60 lb sand tubes on the starboard behind the galley cabinets until it leveled. It took 180 lbs. If the boat is unbalanced, the crossover will not level it by itself.

Still, after a cruise, the boat listed slightly to port because more fuel was getting returned to the port tank than the starboard tank. There is a manifold, but it doesn't seem to balance the flow rate to each tank, plus, the generator returns only to the port tank. I'm not sure what I will do about this. There are shutoff valves on these return lines, and I could shut down the port tank valves very slowly and see if the flow rate to each tank can be balanced that way. Has anyone experience with this approach?
 
I had the same problem. To confirm if it is fuel, I put some painters tape at the fuel level on both sight tubes. Then I went for a cruise. Noticed the level dropped in the port tank but not the stbd at the same level. So I started chasing valves. I found a larger diameter supply line that is supplying fuel to the fuel filters and turned it off.
Redid the tape and noticed the draw down is now the same.

So I filled and now the list is almost gone.

Check your valves. A great time to map it all out also.

Good luck
 

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