View Full Version : Convert from flame arrestor to K&N

05-20-2009, 07:43 AM
I just bought a 06 mobius xlv and it has the 325hp motor in it. It has the round metal type flame arrestor that sits just under the engine cover. Is there a way to convert it where it has a k&n cone style filter? If not, what k&n p/n flame arrestor do I need to just replace the one that comes standard with the boat.

05-20-2009, 09:04 PM
I've also been thinking of doing this for a while. Anyone done it yet???

05-20-2009, 09:17 PM
As long as they are marine approved you won't get fined.

05-20-2009, 09:33 PM
got inspected sunday at the ramp.
watercop asked me where the spark arrestor is. told him I didn't know(cause I don't). he pointed to the air intake that looks just like a k&n. asked me what brand it is. told him I didn't know, that it came with the boat. told him it was an '06 340hp catalyzed motor. he said "new enough, your good" and closed the hatch....
figure most are that easy??

05-20-2009, 09:48 PM
Good comeback. They probably know K&N but don't have a clue what you said at the end. That could work for a long time.

05-21-2009, 05:44 AM
sad thing is I really don't know. it might be a k&n. bought boat as a skiers demo, so I doubt it, but it looks just like ones I have had on my evolutions, and I haven't ever taken it off.
suppose one of these days I'll dig into it, but if the boat runs fine and it's not preventative maintenance, why bother it.

05-21-2009, 06:01 AM
I got hit up by the Water patrol 2 weekends ago and when i opened the hatch he asked me to remove the plastic cover on the engine and he looked at it and said looks like a flame arrestor to me.

I couldnt resist and said well this boat is Fuel injected so theres no carb and hince to flame arrestor.

Hes like good to know and moved on with the inspection.

Got my 09 safety tag on the boat.

05-21-2009, 09:55 AM
yea, I have had many k&n's before, and this one looks just like one. at the end of the air intake, it's just clamped on and open to the engine compartment.
I wouldn't have believed that it's a different filter from factory as the boat was "new" from the factory when we bought it, but it was one of the first '06 models and used in some photo shoots, so maybe the real intakes weren't done yet.

the one thing I will never understand is the grey piece of plastic held on with velcro tabs that simulate intake runners on the top of the intake manifold.. what is the point and why did they feel necessary to put that on? seems a waste of money..

05-21-2009, 10:46 AM
All Indmar 340 CATs have the clamp on K&N Cone style air filter, Indmar stated the 340 CAT Cone setup is not compatible with the 325 ASSAULT.

For those that want a K&N filter use Indmar part #525027 to retro a K&N to replace the flame arrestor, it will look similar to the flame arrestor and not cone shaped. In order for the cone shaped filter to work you would have to have a custom plenum or such.

Here's the page for K&N Marine Flame Arrestors (http://www.knfilters.com/marine/boats.htm)

05-21-2009, 06:44 PM
When i remove the black plastic cover on my engine and there's a silver round, whats looks like an air cleaner, what exactly is that?

Is it an air filter i can upgrade? Doesn't look like an air filter to me.

08 325 assault

05-21-2009, 07:14 PM
Mmandley, that is your Coast Guard certified flame arrestor ... whoopee!

I'm assuming you have the 325 Assault engine, the arrestor can be replaced like i said above with a K&N CG Certified filtered unit but it won't be the cool cone shaped assembly the 340 CAT has. The guy at Indmar really wasn't exactlty sure other than to say "it's flat" so i'm assuming he meant shaped like the arrestor but who knows for sure, he did ask if the cone would work and was told no.

05-21-2009, 08:16 PM
Ok cool Razz

So is it an air filter also then? It just looks strange to me lol. I am tempted to take it off and replace it with a real style air filter but i don't want to be violating anything.

At the local lake here Henry Hagg < i like to hit it on the short for time days > the patrol always comes and talks to me, i think because im the only wake board boat that shows up out there.

Its a small lake maybe 900 acres but only 30 minutes from my house and makes a nice day on the water in a pinch.

05-23-2009, 10:58 PM
Thanks razzman. You answered my question exactly. I wonder if indmar will sell the plenum and other parts to do the upgrade.

05-24-2009, 08:57 AM
They claimed there's not enough clearance for that setup but i have my doubts. They only unknown is the intake manifod and EFI components, they could be totally different not allowing it to work.