engine compartment vacuum

[Sonic Boom]

Anyone add vents to their boat for more engine room air? Engines are not getting enough air with the hatches and doors closed so looking for ideas here. Thank you

 

[Eddieclemons]

I have always wondered about this. My 52c has that one little 4"ish tube coming in from the STB lazarette area.

 

[Bob Quinn]

Anyone add vents to their boat for more engine room air? Engines are not getting enough air with the hatches and doors closed so looking for ideas here. Thank you

I'm guessing everyone is going to ask why you aren't getting enough air and how do you know?
Has something been modified to close off the standard engine room air vents?

On the flip side, I have been trying to figure out a way to add more vent fans, like the floor drying kind that move a ton of air. Not to provide more air to the motors, but to help cool things down after running the engines. My engine room, when hot, makes my ac systems overload and trip. Root cause may be an issue with the AC, but bottom line is the excess heat makes them work "to hard".

The engine room fans blow air out, the engines suck large amounts of air in. I'm guessing if it was an issue Hatteras would have addressed it. Maybe something obstructing your vents?

 

[Bob Quinn]

I have always wondered about this. My 52c has that one little 4"ish tube coming in from the STB lazarette area.

All Hats don't have the 4 foot long engine room vents on the outside walls? That would be unexpected!

 

[Cricket]

Installed Slane's vents and then later added demisters to their airbox under the side deck. Not sure if those vents are still available or not as the molds have bounced around to a few places.
We also cut some holes in the ER back bulkhead that pull air in through our mezzanine.

 

[GCSI]

Eddie: I’m relatively certain Southern Pride has the Slane Vents installed. At refit, quite a bit of effort went into design of the system with full participation of Cat.
Brett

 

[rsmith]

For a period Hatt went to under cockpit air supply in the convertibles mostly due to salt ingestion by the side vents. I believe noise transferred to the cockpit became a problem. I delivered several 46C’s to Ben Hurley in Urbana VA who eliminated the side vents and brought the combustion air from underneath the cockpit.

 

[jim rosenthal]

Was the air supply from the under-cockpit vents enough? I know big diesels require a lot of air, not only for combustion, but for cooling.

 

[Eddieclemons]

Eddie: I’m relatively certain Southern Pride has the Slane Vents installed. At refit, quite a bit of effort went into design of the system with full participation of Cat.Brett

Well I guess I should look closer at the Slanes, I thought they were all looks except for the Exhaust blower outlet. I guess air does come through the Slanes when the exhaust fans are not on.

 

[Eddieclemons]

I'm guessing everyone is going to ask why you aren't getting enough air and how do you know?Has something been modified to close off the standard engine room air vents?On the flip side, I have been trying to figure out a way to add more vent fans, like the floor drying kind that move a ton of air. Not to provide more air to the motors, but to help cool things down after running the engines. My engine room, when hot, makes my ac systems overload and trip. Root cause may be an issue with the AC, but bottom line is the excess heat makes them work "to hard".The engine room fans blow air out, the engines suck large amounts of air in. I'm guessing if it was an issue Hatteras would have addressed it. Maybe something obstructing your vents?

Do you know what your ER is getting up to? After running in the summer if I turn my exhaust fans on it will hit about 110. .I run a carpet fan on low 24/7 so if I open the ER entry hatch it might not even hit 110.

 

[madhatter1]

Anyone add vents to their boat for more engine room air? Engines are not getting enough air with the hatches and doors closed so looking for ideas here. Thank you

I don't see how you could not be getting enough air from under the gunnels in the cockpit through the large openings into the ER. Did someone close yours off? I utilize all that air movement in mine to keep my new second genset nice and dry. I have seen some HP's with side vents added.

 

[Sonic Boom]

I'm guessing everyone is going to ask why you aren't getting enough air and how do you know?
Has something been modified to close off the standard engine room air vents?

There were two hatches in the salon floor that had a gap between them, so I made one larger hatch to make the salon quiet and eliminate the gap in preparation for new carpet. The engines started smoking after this and getting a little soot on the transom. Opened the hatch and ran the boat, this eliminated the smoke and soot.
Nothing has been modified or blocked off that I can see

 

[Sonic Boom]

All Hats don't have the 4 foot long engine room vents on the outside walls? That would be unexpected!

This boat only has air vents in the cockpit, always been curious if this causes the station wagon affect.

 

[madhatter1]

This boat only has air vents in the cockpit, always been curious if this causes the station wagon affect.

I have the same issue. Always thought it might be the four sides enclosure with no back zipper window. Can an 8-92 gulp that much air to create a vaccum void? I wouldn't think so but maybe. I did see a reduction of soot on the transom by dropping pitch on the props. Maybe with your mods you have unloaded engines and you see good results.

 

[Sonic Boom]

I have the same issue. Always thought it might be the four sides enclosure with no back zipper window. Can an 8-92 gulp that much air to create a vaccum void? I wouldn't think so but maybe. I did see a reduction of soot on the transom by dropping pitch on the props. Maybe with your mods you have unloaded engines and you see good results.

my last 46 had the hull side vents and did not have the station wagon affect. Not sure if this was due to the vents or the fact 8v71 naturals don't require as much air. They were literally half the horsepower. Could speed make a difference?

 

[Bob Quinn]

Do you know what your ER is getting up to? After running in the summer if I turn my exhaust fans on it will hit about 110. .I run a carpet fan on low 24/7 so if I open the ER entry hatch it might not even hit 110.

I do not, I should put a thermometer in there. I've been putting one of those carpet fans on the stairway pointed through the nearest engine room door to cool it down quicker. I was thinking about mounting one to the ceiling and pointing it out the side vents. A thermometer would help figure out how hot it gets though. Hard to tell by feel. I know I wouldn't want to go in there when it's hot!