How do you use your blower?

[pindrums]

Paul's Islander 30

1971 Islander 30 with original engine (twice rebuilt). I run it 100% while motoring. I've tried without it different times in different conditions, but the odor down below eventually is too much...(not good engine area sealing properties). I even replaced the original rubber tube set up into the spark arrester with the upgraded kit to better vent the little blow-by internally, but very little cabin odor reduction......

[JDK]

My C&C Corvette does not have any blowers.....the motor is also not enclosed, rather pretty much sits in the middle rear of my cabin.....so I'm "doing the smell test" at all times.....
The fuel tank, 25 gallons, is behind the motor, and when the starboard cockpit compartment lid is off as necessary so I can access the motor controls, I rest one foot against the tank, one against the hull, so I can be seated facing forwards......I also open the rearmost access hatch over the stern when im running......the breeze blows right through and helps carry some heat away.....

[ndutton]

My C&C Corvette does not have any blowers.....the motor is also not enclosed, rather pretty much sits in the middle rear of my cabin

This is a serious safety concern and raises the question of whether or not you had pre-purchase survey. Please read the USCG ventilation requirements provided in the Standards forum category for reference. I just now added the ABYC ventilation standard too.

§183.601 Applicability
This subpart applies to all boats that have gasoline engines for electrical
generation, mechanical power, or propulsion.

Gasoline fumes are heavier than air and even in an open (no deck) hull they will collect in the bilge where a single spark can ignite them. The powered ventilation system is intended to safely evacuate potentially explosive fumes from inside the hull.

[JDK]

Pre purchase surveys ? Are you kidding ? This boat was basicly an abandoned derelict out in the mangroves when I got her, any equipment and setup minus a few things are all original 1967 variety......so I would assume that this particular Corvette, #66 I'm told, never had a forced ventilation system....

[thatch]

"Snooze Alarm"

I run my blower when I'm having trouble staying awake.... Actually, on the first start-up of each trip, I open the engine cover, sniff for fumes and then run the blower for at least one minute before hitting the start switch.
Tom

[JDK]

I wonder what the easiest way to jury rig a blower system would be......I bet it's on the completed projects list that Corvette club members get access to.....too bad the yearly membership fees are out of my league.....

I have spilled small amounts of gas while working on getting her into running condition, it totally stinks out the whole cabin even if it was literally just drops, so I am confident that if there ever was a leak I would be the first to know.....

[thatch]

Probably the simplest setup would be to run a length of 3" collapsable vent hose from the lowest bilge point possible to as far aft as possible to a pull through blower. If there is a clam-shell vent, close by it should be attached there and turned to vent aft. Power should come from a "battery power on" source so it can be run whether the ignition is on or off. Sources like Neil, who are well versed in Coast Guard requirements, should be able to spell out the particulars of an efficient, legal system.
Tom

[ndutton]

I wonder what the easiest way to jury rig a blower system would be......

Since this is about safety I propose a jury rig might not be the best strategy. Probably the same amount of work to do it right anyway, one blower, two cowl vents (one for exhaust, one for fresh supply air), a little 3" flex duct and a switch. The suction duct to the blower goes as low as possible.

I have spilled small amounts of gas while working on getting her into running condition, it totally stinks out the whole cabin even if it was literally just drops, so I am confident that if there ever was a leak I would be the first to know.....

Again, since the fumes are heavier than air the first guy to know is the shortest. A prudent sniff test is with your nose in the bilge, not six feet above it while standing.

Gasoline onboard is serious business. edit: here's how serious. At the boat manufacturers we were always lectured that one cup (8 oz.) of gasoline spilled in the bilge and vaporized has a potential explosive force of three sticks of dynamite. Internet sources vary on this figure from one to sixteen sticks so who do you believe? I don't think it matters much, even the force of a single stick is enough to . . . . well, you know.

[JDK]

I'm not looking to rashly start cutting openings into my deck, but I will begin looking into this as a project....maybe someone on C&C list or the Facebook group has already added this modern upgrade and can show some photos of it turning out looking good like it belongs that way...

[quiesence65]

I have to enter the boat , uncover the engine access, and open two fuel valves, plus open the water thru-hull......and of course I am "sniffing" all this time. Then I turn on the blower......from the cockpit......wait 5 minutes....go below for another look and sniff......then from the cockpit, turn the key and start her up. She usually starts within the first 10 seconds......this from a 52 year old A4!!!........Then I turn off the blower.