Day Tanks for a sailboat

[Michael Gray]

I mentioned in an earlier thread the problems I had encountered with loss of engine power in a Legend 38 sailboat heavy seas and recieved a lot of very useful advice - many thanks. I am looking at the possibility of making/installing a diesel day tank and am hoping that memebers may have experience and advice in this area. My engine is a Yanmar 3 cylinder of 39 hp and I am lookin for a tank size to give around 8+ hours running. I am particulalry interested in understanding the plumbing arrangements and valves (supplying the tank from the return pipe seems a favourite as the fuel has already been filtered). I am a reasonably competent DIYer (what sailor is'nt) and may look to use automotive parts where possible to reduce costs.

 

[fireball]

Based on my previous 2 engines ...
20Hp ~ 2L/hr
30Hp ~ 3L/hr

so ... 40Hp ~ 4L/hr ...
8 hours = 32L ... but that would be tight unless you're going to top up whilst underway ...

 

[electrosys]

I didn't see the earlier thread, but have suffered from aeriation (diesel frothing) myself when crossing shallow water in heavy seas.

Have you considered the other option - fitting a diesel de-aeriator in the fuel line ? Small de-aeriators can be bought from Toolstation (current catalogue p.309) for £12, or you could make your own - recommend a little larger and with a water run-off tap.