Engine room ventilation

[aitchem]

In the middle of a re-engine project.
Current ventilation is by a couple of removable doors in the wall between the quarterberth and engine room.
This has me wondering about the engine's long term health.

Any airflow will be down these holes, into the air intake and out the exhaust.
This seems to be the usual arrangement, but I am debating whether the the engine room will have sufficient circulation within, around the block/ancillaries (alternator) etc.

How would I safely get fresh air into the engine room.?
Of course, one has to consider how, because that rogue wave would swamp the engine room when you need the engine most.

thx
Howard

 

[pvb]

My engine breathes fresh air taken from a locker in the cockpit area, via a length of 90mm diameter ducting which ends close to the alternator, thereby cooling the alternator as well as providing air for combustion. Engine room access doors are well-sealed with foam strip to reduce noise inside the boat.

 

[Deleted member 36384]

My own engine is isolated all-round via access panels and bulkheads. They are sound proofed and reasonably close fitting. The air flow into the engine room is through two vents in cave lockers in the cockpit coamings. The engine bay has a glassed in sump with conduits for the bilge pump hoses (2 x off). So air flow will also come through the bilge.

There will be hot spots in the engine room but I doubt that they will get hot enough to exceed any maximum temperature specification.

Do you have any reason to suspect that the quarter berth doors are not sufficient to allow in enough air?

 

[aitchem]

Thanks guys, the caves might be a place to consider.

I was looking at this webpage, but thought it might be OTT for a little yacht engine, but, you never know.!

http://www.yanmarhelp.com/i_vent.htm

thx
Howard

 

[sailorman]

In the middle of a re-engine project.
Current ventilation is by a couple of removable doors in the wall between the quarterberth and engine room.
This has me wondering about the engine's long term health.

Any airflow will be down these holes, into the air intake and out the exhaust.
This seems to be the usual arrangement, but I am debating whether the the engine room will have sufficient circulation within, around the block/ancillaries (alternator) etc.

How would I safely get fresh air into the engine room.?
Of course, one has to consider how, because that rogue wave would swamp the engine room when you need the engine most.

thx
Howard

Hi Howard
what engine is it

 

[oldsaltoz]

We have a ducted supply of external air that is fed into the lowest point of the engine compatment, this means the cooler air flows over the entire engine on it's way up to the intake.

 

[aitchem]

Hi Howard
what engine is it

Yanmar 2YM15 replacing a Petter mini six.
It's actually shorter than the olld engine/box.

The mini six will be on that well known auction site soon, as soon as I have built an A frame to get the things swapped around.

I think I will make up a cave inlet and make it sealable should I fear a big wave.
It's my thought that the alternator would be the most vunerable item in a hot engine bay.

Howard

 

[sailorman]

Yanmar 2YM15 replacing a Petter mini six.
It's actually shorter than the olld engine/box.

The mini six will be on that well known auction site soon, as soon as I have built an A frame to get the things swapped around.

I think I will make up a cave inlet and make it sealable should I fear a big wave.
It's my thought that the alternator would be the most vunerable item in a hot engine bay.

Howard

My Co32 never had any vents & was perfectly ok
my current set-up is a 4 cylinder 38hp with a vent in the aft end in the lazerette, the liferaft is in front of that so some restriction to air flow.No probs to date in 14 yrs of ownership.
if you ship water it might get down via the cave locker into the engine bay.
dont forget KISS