Forum Discussion and Opinions

[workinpr0gress]

Originally Posted by eggsuckindog

why create more work and labor

I just mean in the existing holes, clean but traditional look, unique, functional.

With the amount of work some people have done I figured someone has it on theirs, but I've never seen it on a CSC.

[gofastsandman]

I think the design of Capt. Chuck`s vents make sense. Flush. I keep learning.

How do your vents shed water?

I`m thinking about this as it got lost along the way.

Cheers,
GFS

[77SceptreOB]

Originally Posted by thehermit

My 1974 vents are original.....and so it's my deck.

Same story on my 1977

[strick]

My 1969 20 sf was factory built without vents...and I did not put any in during the restore...so now I get mildew in the bilge if I do not keep the hatches open when the boat is not in use. Ventilation is a good thing.

strick

[FishMagnet]

Im here to learn from your experience, but Im a seasoned boater and I ve had several boats that didnt have vents and didnt have mildew in the bilge. Is there something particular to the Sea Craft hull that requires this additional ventilation? Do you know of people that have glassed in the vents on a 23 ft remodel and have had problems with their floors or tank subsequently? I can tell you that I am replacing a 3 1/2 year old fuel tank that corroded and pitted despite venting, but I think it was installed poorly.

[thehermit]

FishM,

There are a few here who have glassed 'em. Fellowship is one. I am sure his plywood decks are still fine....you can ask him.

The original vents were very functional. As you have heard...they are responsible for keeping a lot of these old boats in great shape. In short...Good Design. In my opinion (on the 23') the vents dont see a lot of water and dont let much in either.

....dont forget to post pix of the project ;-)

[Bushwacker]

Originally Posted by FishMagnet

. . . I ve had several boats that didnt have vents and didnt have mildew in the bilge. Is there something particular to the Sea Craft hull that requires this additional ventilation?

In the factory brochures in the early 70's, SeaCraft said they didn't foam in their gas tanks because it was a bad idea, i.e., the foam would hold moisture against the tank and cause it to corrode. They said this (lack of foam) required them to ventilate the bilge (maybe a USCG requirement?) which added cost, but said ". . that's just the way it is when you're building a boat to last forever!"

Did your other boats without vents have foamed-in fuel tanks by any chance?

All I know is that my almost 40-year old SeaCraft, which was always an outboard configuration, has hull vents, and it still has the original fuel tank! Fortunately I pulled the tank right after I got the boat when it was 3 years old and found that it was resting on top of a brass nut that had evidently been dropped in the bilge during manufacture! If I hadn't done that I'm sure that the resulting galvanic corrosion would have put a big hole in the tank a couple years later! Fortunately I was able to grind out the pits and seal it with Marine Tex. I painted the whole tank with epoxy and it was in good shape when I pulled it again 6 years ago to clean it and replace hoses when I repowered. The plywood floor under the tank, which is only glassed over on the top side, was also in good shape. I think it might have rotted out by now if the bilge had not been ventilated. Bottom line: I think that the factory knew what they were doing when they installed the vents. If it was my boat, I'd keep 'em!

[BigLew]

I suspect that some governing council; Coast Guard Regs, American Boat Manufactures Association or other such "council" RECOMMENDS ventilation of the below deck areas if the fuel tankage is located below deck.

I have mentioned this anecdote before and, though I truly hate to even think about it, I will relate it again.

When I was in college in the late sixties/early seventies I was at the Univ. of South Carolina. I was a member of their sailing team and we would sail out at Lake Murray outside Columbia. I was out sailing with some friends in the university's boats when I saw a kid about sixteen run out the door of his parent's cottage. He ran across the lawn, down a short dack and jumped in a 16' Donzi. He just reached down and turned the ignition key. He and the boat went up in an exposion of fire and debris. I can't help but think that if the hull was vented and he had run the blower as he was supposed to, he would have made it down for breakfast the next day. As it was, he didn't. I can't ever forget that experience and will forever stop preaching the need to vent a hull AND run the blower AND open the engine hatch before starting engine; outboards included! The consequences are just too potentially devastating not to.

That said, we each have to decide what is safe enough for our selves. However, I think it is Fr. Frank that uses the quote,

A smart man learns from his mistakes.

A wise man learns from the mistakes of others.

I'll shut up now.

[csurf]

This is from "FEDERAL REQUIREMENTS FOR RECREATIONAL BOATS"

Ventilation
All vessels built after April 25, 1940 which use gasoline for electrical generation, mechanical power or propulsion are required to be equipped with a ventilation system.

A natural ventilation system consists of at least two ventilator ducts, fitted with cowls or their equivalent:

A minimum of one intake duct installed so as to extend from the open atmosphere to the lower portion of the bilge; and
A minimum of one exhaust duct installed so as to extend to a point at least midway to the bilge or at least below the level of the carburetor air intake.

A powered ventilation system consists of one or more exhaust blowers. Each intake duct for an exhaust blower should be in the owner one-third of the compartment and above the normal accumulation of bilge water.

Between April 25, 1950 and July 31. 1978, the regulations covering ventilation systems applied to the owner/operator. If your boat was built between April 25, 1940 and July 31, 1978, a natural ventilation system is required for all engine and fuel tank compartments, and other spaces to which explosive or flammable gases and vapors from these compartments may flow, except compartments which are open to the atmosphere. There was no requirement for a powered ventilation system; however, some boats were equipped with a blower.

The Coast Guard Ventilation Standard, a manufacturer requirement, applies to all boats built on or after August 1, 1980. Some builders began manufacturing boats in compliance with the Ventilation Standard as early as August 1978. If you boat was built on or after August 1, 1978 it might have been equipped with either (1) a natural ventilation system, or (2) both a natural ventilation system and a powered ventilation system. If your boat bears a label containing the words, "This boat complies with U.S. Coast Guard safety standards," etc., you can assume that the design of your boat’s ventilation system meets applicable regulations.

Boats build after August 1, 1980 which comply with the Coast Guard Ventilation Standard must display at each ignition switch, a label which contains following information.

Warning
Gasoline vapor can explode. Before starting engine operate blower for at least 4 minutes and check engine compartment bilge for gasoline vapor.

All owners are responsible for keeping their boats’ ventilation system in operating condition. This means making sure openings are free of obstructions, ducts are not blocked or torn` blowers are operating properly and worn out components are replaced with equivalent marine type equipment.

For the CME, all blower motors installed in exhaust ducks must be in working conditions regardless of the date manufacture.

[Mikem8560]

my 20 has them