Storage for portable gen set, Hunter 40.5

[Irek]

Hi guys
Once on a subject of hatches a bit of a new idea. The afterpeak of our boat has two access openings on the top, one on the PS and one on SS. In the middle there is a swimming platform and a ladder. After discussing with pross and measuring thickness of the hull in this are I have dedicded to install there a hatch which will give me up/down access for storing there a 4 kW fully enclosed gen set. The machine is 50 lbs heavy with nice handle on the top.
After some search I found that Genuine Marine hatch from China would have a size suitable for available space. Cut out was made and new hatch installed. Gen set can be stored there while it is not in use. The space can be made gas tight and exhaust gas line could be connected overboard so it could run in there without moving it out, if not for the legalities. Machine has remote control start/stop, protective devices incl. CO alarm. See some pics. No worry about being off the grid. Hot shower and coffe in the morning is now available./ik

 

[Don S/V ILLusion]

As I recall, that area is way too shallow to accommodate any generator plus the laminate there is very thin.

 

[Irek]

Hi Don
I was quite surprise by how thick is hull in this area! I have been planning to add some thickness but it was unnecessary. I also built a little foundation to keep gen set level and position so it will not move when boat is healing. As to the height I still have about 3, 5 cm to spare after closing the lid. Space is air tight, but noise and vibration is still tb seen. For regulatory reason I do not intend to run the gen set when it is in storage, even if I am quite tempted. Analaysis of risks tells that probability of something going wrong is rather small but if something goes wrong consequences could be serious./ik

 

[Benny17441]

Hi guys
Once on a subject of hatches a bit of a new idea. The afterpeak of our boat has two access openings on the top, one on the PS and one on SS. In the middle there is a swimming platform and a ladder. /ik

The actual enclosed space for the generator must have a vent to the outside of the hull at its lowest point. This due to prevent pooling of gasoline or propane fumes as both are heavier than air and in concentration will become explosive. Would not advise to run the portable generator in the enclosed space. It would need provisions for cool intake air and a fan to exhaust fumes and help keep the engine cool. that is besides the discharge for the engine exhaust. Have you considered perhaps the need for an auxiliary fuel tank to extend run time when running A/C or heating overnight?

 

[Irek]

Thx Benny, all well noted. That is why I am tempted to make additional arrangements such as direct exhaust gas overboard and electric fan for cooling I will recommend/follow what regulators say. The thing with the afterpeak on the Hunters is that it is gas tight, separated from the cabin and open on top when you lift the side lids. Fan should be able to blow any gases up into atmosphere. And gen set is fully enclosed and equiped with CO alert.
But as I said in my posting on risk analysis: probability low but consequences could be severe. As gen set is only 50 lbs I can always drag it not deck when in anchorage./ik

 

[jssailem]

Care in your selection of a fan. A typical (low-cost) fan will use a sparky motor. Since the fan is exhausting a potentially explosive gas, you will want to be assured that the fan is designed to be used in a gasoline engine space.

 

[Irek]

Hi Jim, John
I have no intention to run the gen set in the storage position, even if it is tempting and it could be organized with good safety margin. The exhaust line could be connected to the overboard discharge located close to the water level, same as it is with the main engine. As an old tanker man, I would rather use the blower with both side lids open, keeping the atmosphere oxygen-rich to stay outside of the upper explosion level. And at the same time, cooling the engine.
FYI I had a funny situ with the hatch. The only hatch available that could accommodate the portable gen set could be located in China. The hatch was a bit more than USD 200, but the transport was more than USD 400. Nevertheless, the least expensive that was available in our area (and not fitting the parameters of the project) was more than USD 1000. Now time will tell how long the Chinese-made product will last. Looks solid, overengineered, so I am hopeful that I will be able to use it for a while./ik

 

[jssailem]

Your image showed a good looking hatch. Liked the piston helping to hold hatch in place.

 

[Irek]

There were two supports but I have removed one. They can be taken away with push of the button. Good design./ik