J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Help! Lost my stern ventilator cowl covers

Anyone know where I can find a replacement transom ventilator cowl cover? My hiking stick knocked mine into Davy Jone's locker!

Thanks.

Try a marine consignment shop just for the cowl. On Rhapsody the entire assembly is Nicro N10883 which has been discontinued. I believe that the Nicro 10863 will work.

we use a couple of SS screws to keep them attached. I keep them on my list re visits to 4 consignment stores for last few years ... never see them ... probably because they look so bad after 25 years ... but coat of rustoleum white semi gloss makes them look good for a few years.

we used the one for the bow vent to replace one a few years ago ...

How important are they? Can't the engine breathe without them?

The answer is the engine can somewhat breathe without them, but if you do a long engine run, the engine compartment gets very warm. With the cowl vents you put fresh air into the air filter rather than hot air, thus the engine runs better. Also, any fumes generated end up in the boat if the engine compartment is not vented. This could be a safety issue. I noticed the boat smelled better after installing the ventilation cowl to replace the blank plugs that were in the deck. I also replaced the brittle, cracked ventilation hose with the same size flexible aluminum dryer duct.

I put a 16 oz cup in each opening and I use one to hold my beer and one to hold the handheld radio. They also serve as a good rain gauge! I have to admit I hadn't considered the venting of the engine compartment as particularly critical-although my cabin does get a little bit of diesel smell if I have a long day of engine use.

Steve,

You have an acceptable alternate arrangement. If you drink enough beer from those cups, by the end of the day you don't notice the diesel smell.

I thought that one of you motor heads would have quoted the ideal gas law: PV=nRT. If the temperature of the incoming air increases, less volume of air therefore less fuel/air mix... That's why drag racers pack the inlet manifold with ice before heading down the quartermile...

I leave the engine inspection port open, and enjoy the engine noise.

Michael - I haven't used that formula since I took Thermo over 35 years ago, and yes I also had engineering courses that included vacuum tubes.... Good technical memory refresh. For the non-technical, the explanation that cowl vents stop the diesel odors should suffice......

replacement 3" ones are stock in the West Marine web site