[keelcooler]

John, Lots of torn low quality blower hoses out in service, and the owners have no clue because they are not inspecting. INSPECT,INSPECT,INSPECT, the life of you and your family depends on it. Make sure its not torn, shagging or fitted w/a birds nest. Marine centers for the most part sell only crap 3” hoses. Get your new blower hose at Lowes. I replaced my crap, torn hose years ago w/ the foil covered stuff for dryers…much better.

An auto haylon will not eliminate or reduce an explosive fume condition. A haylon only works once a motor box fire has started. It will activate around 250 degrees and displaces the oxygen. If the blowers running it might not starve out that fire. You must have the proper size unit for the space and then add 20% for naturally occurring venting. The auto haylon is effective in the event of an electrical or raw fuel fire in the box.

The posted a4 C&C story has a telling tale. Exploded and burned after refueling. So we had fumes and raw fuel. No fumes in the cabin that the capt or crew could detect. So the fumes were aft. If that carb or a fitting/hose near the motor was involved in all likely hood some one would have detected. She had run extensively during the day. Does not sound like the motor was involved; the blower was running prior to start. I would speculate fuel fill hose or deck fill fitting leak. If the tank was the problem I would think some one would have smelled the fumes early in the day. If the vent hose had failed or become detached it may have been an explosion only.

What Joe found recently is what I would find 90%of the time during postmortem inspections on an explosion after a refueling loss. FUEL FILLS…don’t let yours be out of sight and out of mind.

You would not believe how may times I’ve seen a broken/rusted out fill system fail after the owner inserted the fuel pump nozzle. “How much now honey…35 gallons…that’s imposable we have a 25 gallon tank” or the power boat that pumps 100 gallons into his bilge! Funny thing, when it’s that fuel rich of a mixture they rarely blow or burn.

Mark, I think with all of the above facts we can draw our own conclusions. I just can’t see how it does any good. I have a haylon and if a box fire erupts I want that haylon to do its job and not have all its flame smothering gas sucked out. I think the engineers at Jabsco or Attwood would advise to use as directed. I think Dave is the only member that has an heavy duty 4” extended run blower that can safely operate all day w/out over heating. The rest of us have intermittent use rated units. I recall the continuous heavy duty rated should be replaced every 10,000 hrs where in ours should be replaced every 100 hrs of use This spec is not because it might fail, its because the spark shielding degrades.