Fuel Crossover

vernh59

vernh59

New Member
Oct 21, 2008
219
Mobile, Al
Boat Info
355 AC
Engines
165 Crusader
One of things I always thought was missing on my boat is a fuel crossover system. My starboard engine and gen share the same tank while the port engine has it's own. After a prolonged use of the gen I can have one tank almost useless while the other is full. I would like to feed the gen out of either side. Does anyone have a diagram of their crossover system? How is yours setup?

Since it's a rainy day here in PC I'm in the bilge cleaning up a bit and I would like to get this project behind me.

Thanks in advance
 
Go on to SeaRay.com and pull up the parts manual for any of the larger boats and you will see a diagram of how the crossover system is set up. My boat has one and I have to tell you that is 5 seasons of ownership I have never really used it.
 
It seems like a crossover would be handy when filling so you don't have to fill one tank and then switch to fill the other tank too. Sometimes it's pain moving to the other side. On second thought, if I had to crawl down in the engine room to open the valve and then shut it again that wouldn't be so handy!
 
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I have never really understood why either main engine can draw from either tank, but the generator is stuck.... I, too, would like to have a selector valve for the generator to draw from either tank. As it stands, I use the mains to balance out fuel usage when we use the generator for long periods. Unfortunately, it doesn't take very long!
 
Sundancer said:
It seems like a crossover would be handy when filling so you don't have to fill one tank and then switch to fill the other tank too. Sometimes it's pain moving to the other side. On second thought, if I had to crawl down in the engine room to open the valve and then shut it again that wouldn't be so handy!
Click to expand...

The crossover only controls which tank the mains each draw from. You can not use it to transfer fuel from one tank to the other so it would not help as you have suggested above. It has occured to me when I have pushed the limit on fuel range that if I ran out of fuel in one tank I could turn the valve to draw fuel for both engins from the remaining tank. Never the less I have only ever left the valves set to have each engine draw from it corresponding tank on the same size. I guess in the end it is cool to have but I dont think I would spend much time or money to add it if I didn't have it. Just my .02.
 
I had the crossover on my 1993 330DA and I have it now on my 410DA. Like others here, I've never used the valves to draw fuel from alternate tanks. I only use the valves to shut fuel flow when changing the racors on my 410DA.

However, after reading this post, I got to thinking that it may not be a bad idea to periodically switch tank draw if for no other reason than to use up the 'stale' fuel that is laying in the lines.

I'll have to remember to do that next spring.
 
Got it, never used it in 5 seasons. For long range cruising and if you run you genny ALL THE TIME, I suppose it could come in handy. I'm sure it'd be helpful on a Grand Banks or a Defever. But I'm with Jon - wouldn't go nuts installing a system if it wasn't already there.
 
from the 370 parts manual - note this only describes the feeds for your mains, but you can mod it to be gen feed by using one of the sides as an example. You'll need to make sure that the port tank has a tap on top for an additional fuel feed, and then you'll need to get a pickup tube and fitting for that side. Then, a simple 3 way will allow you to feed the gen from either tank, and shut it off completely if needed.
 

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I've used mine... If I'm anchored out for a weekend with the generator running, it'll make a big dent in the port tank (like 50 gallons a day)... and like Matt said, I will run the mains off the starboard tank to balance it out.
 
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Thanks for all the replies. I didn't think about a parts diagram. All I really want is to feed the generator from either side. If I can balance the fuel usage by the generator, the mains will take care of themselves.
 
The 540 CPMY has a factory installed cross over system. The system is simple. It is a large stainless steel flexible hose with a ball value on each end that is connected close to the bottom of the tanks. The fuel level in each tank is balanced all of the time and filling the tanks is easy, because you only need to fill one. I would estimate that the hose is 2.5-3 inches in diameter. The system is totally passive.

Mr Salt
2001 540 CPMY
Caterpillar C-12s
Cape May, NJ
 
On my '89 340da Sea Ray kind of took care of the situation for me. I have the crossover system and I also have never used it, but on the Sundancer the 2 fuel tanks are under the mid cabin berth. Starboard tank is 82 gallons and the port tank is 90 gallons. The genny runs off the port tank so it kind of balances itself.
 
This is a very important option. I know a couple that were traveling to Bimini from Miami. About 30 miles out the weather suddenly became seriously rough. They made the decision to turn around and head back to Miami. Shortly thereafter they lost an engine, but could maintain course with the second. Because of the sea conditions and the single engine, their speed was extremely slow. As it turned out, they ran out of gas on their approach to Government Cut because they could not draw fuel from the non-working engine’s fuel tank.
The boat ended up on the rocks. Luckily, because of the fine work of the Coast Guard, everyone on board survived. This deadly situation could have been avoided if they had a fuel crossover line.
 
Just Ducky has every Sea Ray option offered, except one. When I asked the dealer why, he told me that sometimes the fuel crossover valves for gasoline engines will leak. They don't want customers to deal with leaking valves, so they don't bring any gas boats in with that option. All of the diesel boats do have them. Diesel fuel doesn't wreck the seals like gasoline. If you have crossover valves, check them frequently, probably as often as you check the oil. IE:Every day.

Best regards,
Frank
 
I do have a crossover. They do not leak but I'd be afraid to touch them. Probably only in an emergency.
 
Four Suns said:
I've used mine... If I'm anchored out for a weekend with the generator running, it'll make a big dent in the port tank (like 50 gallons a day)... and like Matt said, I will run the mains off the starboard tank to balance it out.
Click to expand...

Holy smokes, 50 gal/day? I always used the rule of thumb 1 gallon/hour. That's an expensive weekend :)

-T
 
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