Spark Arresters

[clayman]

Hey Guys, I was at the Turkey Rod run this weekend buying parts for the old Donzi and I was looking for a nice air cleaner. know one could tell me what the differences between a regular air cleaner and a USCG approved aircleaner. What is the difference. I took a good look at a Gaffrig approved arrester and all it had was wire mesh for a filter, so wouldn't a K&N filter do the same thing? the internals were the same too, I expected some special shields or something.
Thanks for you help.
James

[Gearhead99]

You have to run a Flame Arrester vs Air Filter. The Flame Arrester contains backfire, which stops the boat from blowing up. Fumes settle, heavier then air, but can only go as low as the boat bottom in the bilge. That's why we have blowers to exhaust these fumes. The Arrester contains the a backfire flame.

A normal auto air filter, including K & N would allow a fire. Even burning of the element. An element isn't used on most boat motors cause of the water enviroment doesn't have alot of air borne dirt.

They do make Flame Arrestors with a K&N filter on the outside of it. I like that idea. You get the best of both.

[Formula Jr]

Can somebody explain to me how these things work?
I mean they are just closely spaced plates or fine mess like that used in a Marine Alternator. How does this work. Do the close spaces just limit the available oxygen so the flame front runs out?

[Looped]

I too have been wondering about the differences of the auto air cleaners and the flame arrestors. Is it just the filter that makes the difference or is it the metal casing of the flame arrestors that hold up better in case of a carb backfire? I have been thinking of getting a dual side air cleaner (possible clearance issues) from Holley that I see used on many low profile marine power charger engines that I thought only had some flame arrestor filter.

Holley Part #64280 or #90633
http://www.donzi.net/photos/holleyac.jpg

Craig

[Formula Jr]

I have a K and N CG approved filter. I can't see any differences between it and the regular K and N Filters. But the whole flame arrester aspect still eludes me. How does a fine wire mess stop the propagation of a flame. It must work, otherwise it would not be required, but how does it work? I've also always wondered about distributors. Here you've got a rotor blasting these long spark arcs to the plug wires, yet its somehow safe.

[MAXCAT]

formula, The plates or mesh provide a large amount of surface area. When the flame propagates along the cold metal it is quenched. The more surface area the better.

[RickSE]

From what I've seen looks like the CG approved K&N filter comes with a stainless steel top & bottom while all other K&N's have chromed steel housings.

[Bryan Tuvell 33ZX]

Great topic, I have a K&N marine arrestor coming.

Here are the quotes from their site.

Marine approved per SAE J1928 standard.
Smoothes and straightens incoming air.
Increases horsepower up to 15%.
29% more airflow than other flame arrestors.
Washable and Reusable.

[clayman]

Well I am glad I posted this question, seems others are interested as well. I am thinking that maybe K&N just put the one housing design through the USCG approval process, that is why that one in particular is approved over the others. I think I will call them tomorrow and see if I can get the skinny on this.