NC11 Outboard Motor Storage

[solmate11]

Any advice on where to store a  4 stroke 57 lb dingy outboard motor on the NC11 while under way? Engine compartment? 

[belmar]

Hi, 
Having an Torqeedo outboard I store it in under first hatch inside. But for a gas outboard I guess the engine compartment is the only right place to store. When you do not have an generator in there you can remove the board running between the two battery banks and make a fitted storage for the outboard. Mind the gas in that compartment by the way: it is of course a good ventilated room but only when the engines are running so perhaps you should add a ventilator and use it when you start up your diesels to prevent explosion of any leaked gasoline: ask somebody who is familiar with gas engine's. 

[rene460]

Hi solmate,

At first I was inclined to agree that a bracket in the engine/generator space might be good, but when I realised. You had a diesel engine I concluded that it is a very bad idea.

The issue is that the petrol fumes which will vent from your outboard, despite the little vent closure screw, and especially in the heat of your engine compartment, are heavy gas and very highly explosive.  The engine compartment is not sealed around the bottom, and the fumes will escape into the rest of your boat. You might like the smell if you are a petrol head, but more important, you can be very sure they will eventually find an ignition source, a tiny electrical spark will do it.

The engine compartment ventilation system on most boats does not draw from low down in the engine compartment as is necessary to remove heavy gas fumes.  I have seen even big name petrol engine driven boats which had all the ventilation pipes drawing from the top.  Admittedly explosions are few, but they are very bad when they happen.

I suggest the best place is a suitable bracket which puts the engine over the back, like you will have seen on many yachts, and is the safe answer, if you do not have a suitable locker with similar sealing and venting to the outside like a gas locker.  It is very similar heavy gas from the safety point of view.  I am not familiar enough with your boat cockpit design to make a more specific suggestion for location.

If the bottom of the leg tends to rub, make a little pad from a plastic kitchen cutting board.  Cuts and drills easily and cheap in many colours.  Stick it on with sikaflex and some self tapping screws.  And perhaps make a clip and elastic strap tie down to stop the lower leg moving around in rough conditions.

rene460

[belmar]

Jun 27, 2017 4:43:02 GMT rene460 said:

Hi solmate,

At first I was inclined to agree that a bracket in the engine/generator space might be good, but when I realised. You had a diesel engine I concluded that it is a very bad idea.

The issue is that the petrol fumes which will vent from your outboard, despite the little vent closure screw, and especially in the heat of your engine compartment, are heavy gas and very highly explosive.  The engine compartment is not sealed around the bottom, and the fumes will escape into the rest of your boat. You might like the smell if you are a petrol head, but more important, you can be very sure they will eventually find an ignition source, a tiny electrical spark will do it.

The engine compartment ventilation system on most boats does not draw from low down in the engine compartment as is necessary to remove heavy gas fumes.  I have seen even big name petrol engine driven boats which had all the ventilation pipes drawing from the top.  Admittedly explosions are few, but they are very bad when they happen.

I suggest the best place is a suitable bracket which puts the engine over the back, like you will have seen on many yachts, and is the safe answer, if you do not have a suitable locker with similar sealing and venting to the outside like a gas locker.  It is very similar heavy gas from the safety point of view.  I am not familiar enough with your boat cockpit design to make a more specific suggestion for location.

If the bottom of the leg tends to rub, make a little pad from a plastic kitchen cutting board.  Cuts and drills easily and cheap in many colours.  Stick it on with sikaflex and some self tapping screws.  And perhaps make a clip and elastic strap tie down to stop the lower leg moving around in rough conditions.

rene460

I guess this is the answer of an gas expert😊. Although the engineroom temperature does not exeed 95°F and the engine compartment is sealed of, but done in a French way so there are leaks. In the end I agree with Rene that it might not be the right solution: especially while the battery banks are in the same compartment. I thought of an alternative, other than hanging it over the back. Perhaps it will fit in the rear bench: there is no electricity there and no leaks to the interior.... Jeanneau always forgets to seal the back lid so water and air will come in there, but also under the seat which is not sealed either, and there are vent holes in the bottom so fumes can escape. 
I am part of a small NC11 owner group and I will ask if somebody has a gas outbord and how they store it....to be continued....

[solmate11]

Thank you Belmar and Rene460.  I understand the gas fume issue.  Yes, I have a generator along with the engines and battery suite in the engine compartment.  The  back bench has a single bar rail. However, the entire seat structure does not appear strong enough to support the motor with a stand. Still seeking a solution....

[belmar]

Just received a answer from one of the NC11 user group members:
"I have a Yamaha F6 outboard and use it exclusively with an external fuel tank.
The engine is stored in the engine compartment. The fuel tank (with vent closed) is stored in the aft bench. I have never smelled any fuel smell there.
The outboard’s internal fuel tank has never been used. Before stopping the engine prior to storage, I disconnect the external fuel tank and let the engine run a minute (or so) until it stops by itself. This way, the engine is clean from any fuel."

Hope this is helpful

[solmate11]

Belmar,

Thanks.  That is a great solution. I have the Tohatsu 4hp with an external fuel connection.  This solution should work.  Do you know if this person has any special set up for securing the outboard in the engine compartment for a bumpy ride or the oil that is in the outboard sump?

[belmar]

Hi,
I have sent you a message.

[rene460]

Hi Belmar,  you have me pegged.  It probably makes me overcautious.

I was was not aware of the engine compartment sealing in your boats.  In my sailing vessel, coolant spilt in the engine compartment by a careless mechanic certainly finds its way to under the floorboards in the main saloon.  Vapour would also.

The sealing would help with containment of smells and fluids, however the presence of batteries and generators suggests they only expected diesel fuel in there, not petrol, (known as gas in some parts).  It may be necessary to make sure the ventilation system draws from low down, and looking at when it needs to run, possibly increasing the run time.

Sensible precautions as you have described will prevent most problems, and problems do not happen often.  But accidents usually only happen when several things go wrong at the same time, often things assumed to be not connected.  It is desirable to have multiple layers of protection.  It is conservative, but safer to avoid removing a layer of protection.  But practicalities are also important to consider.  

Generally, the science says you need fuel plus oxygen plus an ignition source to have a fire, and you only have to remove one of the three.  But the oil and gas industry experience is that if you have the first two, the ignition source comes for free eventually.

Just my very conservative two cents worth to include in the considerations.  Crossing the road and driving are also dangerous but cannot be avoided these days. Sometimes we have to be vigilant and cautiously proceed anyway.

rene460

[solmate11]

Thank you Rene for the sensible advice.  I am in complete agreement.
Belmar, thank you for the relay!

[nigelnc11]

old posts but I would never store an outboard with fuel in tank in the rear storage compartment. There are no petrol blowers to clear the fumes. This is extremely dangerous. Diesels don't require blowers. Petrol blowers are a special type that don't spark, plus you need to run for 4 minutes before starting! 


I store our two stoke outboard in rear seat compartment. Or as previous poster noted, you keep fuel there in a separate tank and the outboard with NO fuel in it in lazarette.