Atomic 4 Gasoline engine

[sailortype]

but then I think.... the hose on most sailboats is in the bilge so you are not evacuating the engine compartment per se other than indirectly; you are evacuating the bilge (of course where all the heavy fumes have gathered). And most of the air would come from the cabin, not the engine compartment.
Technically should there be another hose opening in the engine compartment?

[Scot McPherson]

Originally Posted by sailortype

but then I think.... the hose on most sailboats is in the bilge so you are not evacuating the engine compartment per se other than indirectly; you are evacuating the bilge (of course where all the heavy fumes have gathered). And most of the air would come from the cabin, not the engine compartment.
Technically should there be another hose opening in the engine compartment?

Again, it's baffled...

Below the cabin is the sole, below the sole is the bilge....where as the cabin might have hatches and companionway open, free flowing air all around, but the fumes are still baffled in the bilge and engine compartment.

yes there is _some_ movement of air, but it's baffled...it's not free flowing.

Below the engine compartment is...just the bilge...

The fumes won't want to rise as easily due to the sole getting into the way and all the nooks and crannies the fumes have to travel through to get under your sole anyway, where as in the engine compartment, the fumes can just build up.

You may be fine 99 out of 100 times or even 999 out of 1000 times, but it's that one time where the fumes built up enough....boom.

it's prevention, that's all it is...kids don't jump in pools to drown every day either, but we still put up fences to prevent that 1 in a million chance right? same idea.

[Adelie]

Originally Posted by 30yearslater

Here is an overlooked issue. Load arm. The A4 weighs in at 310 pounds. A direct replacement Beta 14 weighs in at 196 pounds. The 114 pound difference seems minimal yet when considering the location in the bowels of the boat the loss of the weight down low will affect the CG of the boat. I considered a change out of my A4 for the Beta but I can replace the A4 1.5 to 2 times for the cost of the Beta. It isn't a quick switch out as muffler, high rise manifold, exhaust fitting, additional tank fitting for return, exhaust hoses at 2" instead of 1-5/8" plus hoist in and out. A basic beta engine and transmission only hits $8100.00 while a new block, manifold, head, etc A4 from Moyer is $6875.00. That includes electronic ignition with electric fuel pump and oil pressure cutout. A few upgrades make better sense than going diesel. With reasonable care a gas engine is no more dangerous than a diesel. In fact I've been privy to a sooted diesel starting a fire and can't say the same about gas.

Looking at the line drawing ( MORGAN 30 )it looks like the engine is about 12" below the waterline which is at or a bit above the CG. Loosing 114lb there would not affect the righting moment and might help it slightly.

[30yearslater]

Originally Posted by Adelie

Looking at the line drawing ( MORGAN 30 )it looks like the engine is about 12" below the waterline which is at or a bit above the CG. Loosing 114lb there would not affect the righting moment and might help it slightly.

Here is a look at how much higher the Beta sits. This was provided by Beta Marine. Notice how the A4 has the huge cast iron oil pan. No doubt a source of its' heavier weight.