Venting I/O engine compartment necessary after towing?

[martymudskipper]

Re: Venting I/O engine compartment necessary after towing?

Thanks everyone for sharing your experiences, I'll use them for my fishing partners who have told me that it's not necessary after trailering the boat, I've put a small reminder near the ignition to remind me to ALWAYS inspect, sniff, and blow before getting started, in the grand scheme this is such a small inconvenience that could prevent a huge inconvenience, like loss of life and/or limb. I can't see ever being in such a hurry at the launch to not do this but there are occasions when I'll need to get it started quickly during the day to avoid impact with a petroleum platform or floating object. I've owned may I/Os and have always been bad about this, I've been lucky but I think it's time to stop playing Russian Roulette. Thanks again.

 

[rndn]

Re: Venting I/O engine compartment necessary after towing?

There were pictures floating around this site of what was left of a boat that decided not to vent. For something so dangerous why don't they install an ignition lockout if the blower is not running for a specified time??

 

[45Auto]

Re: Venting I/O engine compartment necessary after towing?

I can just see the lawyers lined up to sue a boat manufacturer when somebody is run down by an ocean liner because they couldn't get their boat cranked waiting on a blower timer ............

Or somebodies kid drowns because the boat that saw them in trouble wouldn't crank because it was waiting on the blower timer ...........

There could be times when it might be prudent to accept the risk of an explosion and crank the boat RIGHT NOW!!! Guess it comes down to accepting personal responsibility. I don't need anybody putting some mechanical control on how long I need to run my blower before the boat cranks. I'm capable of looking at the information and risks and making my own decision.

 

[Caveman Charlie]

Re: Venting I/O engine compartment necessary after towing?

Oh ferchrissakes..on start, and not on plane, run the darn blower....no if's, ands or buts ...why would you NOT want too..?

Well, for one thing if I run it for five minutes. Then run it under way. Then stop and move 3 times while running it for 5 minuets each time. Then I think my battery would probley be dead and I be in the water waving at people with my jumper cables in my hand. And, when you hook them up the spark is going to be much worse and more likely to cause a explosion.

I wonder how much a marine blower draws????

 

[45Auto]

Re: Venting I/O engine compartment necessary after towing?

A typical 3" boat blower draws about 3 amps. A 4" boat blower draws about 4.5 amps (http://www.boatersland.com/blowers.html). A Group 27 battery is usually rated at 90 amp hours. Shouldn't be any problem to run your blower for several hours then crank your boat motor, much less run it 5 minutes at a time then crank the boat and recharge the battery.

 

[Scaaty]

Re: Venting I/O engine compartment necessary after towing?

Well, for one thing if I run it for five minutes. Then run it under way. Then stop and move 3 times while running it for 5 minuets each time. Then I think my battery would probley be dead and I be in the water waving at people with my jumper cables in my hand. And, when you hook them up the spark is going to be much worse and more likely to cause a explosion.

I wonder how much a marine blower draws????

OK, let me put this is Caveman terms..maybe you will understand.
Most blowers do 150CFM (draw zip..'bout the same as all lights on..smoke lighter draws more than a few minutes blower time).
That said, lets do the math.
(Remember, fumes sink, heavier than air.)
A 4x4 doghouse holds 64 cubic feet..but lets do 6x6 (216), and do the total bilge as a added total, and remember 90% is laying on the bottom.
SOooo, yer looking at a minute plus on with a solid fuel system.
My take is ALWAYS run the blower 3 minutes after sitting a week,..(unless ya got a 80 foot yacht..we are talking small I/O's here).
Ya just shut it off? 30 minutes later a restart?..30 seconds good to go. Thats 60+cubic feet gone.
I would always suggest a good few minutes after a refuel, towed or not..(what if some fuel connection jostled loose during the tow?)
I think the 5 minute thing is solid lawyer speak..do the math on the cubic feet to clear the bilge on a good working blower..5 minutes would (in my opinion), have Al Gore looking for yer "Carbon Credit card"..)
That said, after a decide to leave the naked beach area, because the fat ones showed up, is hit the blower, make sure ya all ready, fire it, plane her out, shut it off, and live with memory of the fat ones...pretty simple..5 minutes is BS on a small I/O with a solid fuel system...but thats my opinion
PS...ALL carbs might/will percolate with heat after shut off out the throttle linkage, I get a few drips out my brand new Edelbrock Marine on a hot shut off.
Remember. one drop gas, 14 drops air, and boom!
Dont belive me? Drop a single drop in a glass Mason jar, wait while ya get the match, then toss it in. Watch those eyebrows...

 

[ziggy]

Re: Venting I/O engine compartment necessary after towing?

what if some fuel connection jostled loose during the tow?

that has happened to me..........my connection got knocked off, but the outcome was the same........ i was probably a spark away from blowing up and didn't know it....... don't know if i didn't ever make the spark or if my blower did it's job. my blower was on for 3-5 min during launching prior to turning the key..... it sure is darn scary to think about that idea...blowing up with the turn of a key that is......

 

[rocky100]

Re: Venting I/O engine compartment necessary after towing?

I made it a habit of turning on the blower the second i get on the boat, running it for 5 mins before cranking (with the lid up).
I also run the blower all the time-never turn it off till I`m back at the dock.
Never had a problem yet.

 

[Caveman Charlie]

Re: Venting I/O engine compartment necessary after towing?

OK, let me put this is Caveman terms..maybe you will understand.
Most blowers do 150CFM (draw zip..'bout the same as all lights on..smoke lighter draws more than a few minutes blower time).
That said, lets do the math.
(Remember, fumes sink, heavier than air.)
A 4x4 doghouse holds 64 cubic feet..but lets do 6x6 (216), and do the total bilge as a added total, and remember 90% is laying on the bottom.
SOooo, yer looking at a minute plus on with a solid fuel system.
My take is ALWAYS run the blower 3 minutes after sitting a week,..(unless ya got a 80 foot yacht..we are talking small I/O's here).
Ya just shut it off? 30 minutes later a restart?..30 seconds good to go. Thats 60+cubic feet gone.
I would always suggest a good few minutes after a refuel, towed or not..(what if some fuel connection jostled loose during the tow?)
I think the 5 minute thing is solid lawyer speak..do the math on the cubic feet to clear the bilge on a good working blower..5 minutes would (in my opinion), have Al Gore looking for yer "Carbon Credit card"..)
That said, after a decide to leave the naked beach area, because the fat ones showed up, is hit the blower, make sure ya all ready, fire it, plane her out, shut it off, and live with memory of the fat ones...pretty simple..5 minutes is BS on a small I/O with a solid fuel system...but thats my opinion
PS...ALL carbs might/will percolate with heat after shut off out the throttle linkage, I get a few drips out my brand new Edelbrock Marine on a hot shut off.
Remember. one drop gas, 14 drops air, and boom!
Dont belive me? Drop a single drop in a glass Mason jar, wait while ya get the match, then toss it in. Watch those eyebrows...

Well, in a way that's what I was thinking. When I get to the unloading area I flip open the cowling over the engine and turn on the fan. It takes me about 5 minute to launch. Then I run it for I suppose a couple of minuets before each start on the water. I don't have a clock in the boat so I have to just guess. I run it almost all the time while boating unless I know I'm going a long ways up on plane. The person I got the boat from told me to do it this way. It's a 1973 boat so if they went up like firecrackers all the time how would there ever get to be old boats? The writing on the dash says you only have to run it for two minutes.

As far as how much the blower draws. It sounds like a efficient blower just by listening to it. But, the blower motor on your car draws a lot! It's one of , if not the biggest, electrical load on your my car. But, that is blower designed to do a different thing. That's why I asked.

The man that sold me the boat threw in a pair of jumper cables. I figure that's a bad sign. That's why I'm apprehensive about to much electrical draws. But, he had cigarette lighter in there he wired in himself. (quite badly I might add) and he was running a beer cooler all the time. I unhooked that thing right away. The depth finder is powered by some old lighter speaker wire. I plan to rewire that this winter. The wires under the dash look like spaghetti but, every thing works . Except for the amp meter Nothing seems to be fused. Except the ignition switch. I put a fuse in that line when I could not get the boat to start due to a bad neutral safety switch. So, I used a extension cord to run new wires from the ignition switch all the way back to the solenoid on the starter.

 

[Bry21317]

Re: Venting I/O engine compartment necessary after towing?

I agree, I run my blower all the time. Never had a problem with it. I sure do not want to go Boom, so I would rather that blower be running all the time.

Bryan

 

[Jerico]

Re: Venting I/O engine compartment necessary after towing?

I run mine 3-5 minutes before starting at launch, an absolute minimum of a 2-5 of minutes before starting after sitting depending on how fast I need to move. If I'm going to run any distance on plane I will turn it off if I remember to. Otherwise it pretty well stays on, especially if I'm idling or moving slow like in a no wake zone.

I figure if it's not on enough it could be hazardous to my health. On too much and worst case I have better than adequate air flow.

 

[Scaaty]

Re: Venting I/O engine compartment necessary after towing?

and he was running a beer cooler all the time. I unhooked that thing right away. .

Well, that thing will draw a LOT!. That said, just use common sense. Seems its a new boat to you, so you will get a better feel for it down the road. Just make sure you have a solid fuel delivery system, thats the main thing.
On the blower, I can't tell ya the number of times I forgot and DIDN'T run it, and the times I left it on for miles on plane...I need a light put in...

 

[Caveman Charlie]

Re: Venting I/O engine compartment necessary after towing?

A light would be a good idea. Someone said something about putting a timer on it before you could star the engine. But, it was pointed out that in a emergency this would be a bad idea. How about a ignitions switch that has the timer for the blower but, with a emergency over ride button next to it that would disable the timer that you could push in a emergency. Put the button under a cover so it's kinda inconvenient to use to discourage using it all the time. Or, maybe a ignitions switch that you could push in and turn back wards to start in a emergency. Like those lawn mowers with the stupid no cut in reverse feature.

 

[Scaaty]

Re: Venting I/O engine compartment necessary after towing?

Little Velcro and a cheap egg timer?

 

[Hitech]

Re: Venting I/O engine compartment necessary after towing?

On the blower, I can't tell ya the number of times I forgot and DIDN'T run it, and the times I left it on for miles on plane...

When I rented I/Os and was (still am actually) new to all this, I just left the blower on all the time. I figured I couldn't forget that way, and it would always have run long enough.