Cleaning Flame Arrestor

[squeeg333]

I was curious what you guys did for cleaning the flame arrestor? I didn't do it prior to putting my baby away for the winter, but wanted to start out with a clean flame arrestor this year. You guys just use carb cleaner or brake cleaner or something, then hose it off and let it dry??

I'm also curious, when you guys take them off, are they pretty tough to remove? I had a hell of a time getting mine off, even with the hose clamp completely loose.

[brain_rinse]

Yep, carb cleaner here. They are stuck on there pretty good, and get hung up on the risers for the engine cover.

[deerfield]

I had a hell of a time getting mine off, even with the hose clamp completely loose.

squeeg - How did you finally get the flame arrestor off? Try as I might, for the life of me I could not get it off of the 325 EFI in my '07 Outback. Yes, I took the hose clamp off. Short of taking a sledge hammer to it, I think the flame arrestor is there to stay. - Deerfield

[brain_rinse]

Assuming it's the same as my 08 LSV, it's just pinched on, albeit very tightly. With some twisting and a few taps from a rubber mallet I was able to convince mine to come off. You should be able to see grooves around the base that with some gentle prying should break it loose if nothing else. Also make sure it's not getting hung up on those risers... you definitely have to come straight up with it.

[squeeg333]

Deerfield - I finally was able to get it off. But I was doing it with the boat on the trailer, in the water, running (so I could spray fogging oil in the intake). My wife, and a buddy were sitting there, waiting, for what seemed like 10 minutes. God is was frustrating, and embarrasing.
I figured that it would easily slide off, and if not, not take too much to get it off. I think I ended up using a screw driver and somewhat pryed it off. Didn't damage anything, but I think like Brain_rinse said, nothing a rubber mallet couldn't handle.

I understand them neededing these "flame tight", but damn!!

[mmandley]

Just an FYI on all EFI engines, the item your calling a flame arrestor isnt that at all. Only Carb engines have a flame arrestor. Its a glorified air filter now. Not sure if it even needs to be removed if your running EFI.

[brain_rinse]

Just an FYI on all EFI engines, the item your calling a flame arrestor isnt that at all. Only Carb engines have a flame arrestor. Its a glorified air filter now. Not sure if it even needs to be removed if your running EFI.
It's still a flame arrestor, check your manual. And it needs to be cleaned as part of scheduled maintenance.

[mmandley]

It's still a flame arrestor, check your manual. And it needs to be cleaned as part of scheduled maintenance.

I'll take your word on this, i dont recall hearing anything about this needing service as its a fuel injected engine. I will look into it more though, i know on my yearly Sheriff inspection they dont care to see it after i tell them my engine is fuel injected, they only need it there if its a Carb engine.

If its cleanable ill be pulling it off and doing the clean thats for sure.

Thanks Brain

[deepcove]

Mine comes off with a Hex bolt thru the top. I remove it and spray it with Wurth brake dust remover.....this crap cleans anything and dries off in a matter of seconds.

[brain_rinse]

Once you've broken it loose once it's really quick and easy to clean. The maintenance schedule says to clean it every 100 hours.

From the Indmar manual: Your engine is equipped with a U.S. Coast Guard approved flame arrestor. Its purpose is to contain any backfire that may occur during operation of your engine. Because an inboard engine is completely enclosed, an uncontained backfire can be extremely dangerous. Periodically inspect flame arrestor to prevent clogging by dirt or corrosion. The metal flame arrestor is cleaned using a mild part washing solvent. Using solvent, clean the flame arrestor thoroughly and blow dry. The metal flame arrestor must be completely dry before it is returned to the engine.

[Wake Master]

If you have a newer EFI engine more than likley you have a K&N filter. You should get the K&N recharge kit. It contains a solvent to clean the filter and an Oil spray to recharge the filter.

[brain_rinse]

They are K&N, but they are metal, not the type that requires the oil recharge.

[DOCDRS]

Here it is from K&N

Washable and Reusable
The oiled cotton gauze and epoxied screen element in K&N’s Flame Arrestor is a one-time investment. A quick service every 500 engine hours or so is all it takes to restore the filter to its original efficiency. K&N is the world leader in advanced air filtration technology for high performance engines. The introduction of the K&N Flame Arrestor represents a significant innovation for marine engine applications. Never before has there been a product that can single-handedly improve horsepower by as much as 15 percent, satisfy Coast Guard regulations and offer critical engine protection.

THe carbed engines have an all metal flame arrestor

Some how i think 500 hours is a little long , id wash it after every 100 hours imo

[brain_rinse]

DOCDRS, you have a Supra that may be different, but the new Moombas I've seen have an all metal flame arrestor, and the maintenance schedule says to clean it every 100 hours. The oiled cotton types do require a recharge, but the all metal ones don't. Just clean, dry, reinstall.

[brain_rinse]

If anyone has any doubts check your manual. It's all in there.

[DOCDRS]

brian, i have a 340 cat ext which is also on the moombas, I think it is just these motors that have the cotton ones, the 325's and 310's as you have, must have the all metal

[Wake Master]

If you click the word "service" on the K&N web site for the Marine filters this is there explaination of service.

K&N Air Filter Cleaning Instructions


1. APPLY CLEANER

FOLLOW ALL SAFETY INSTRUCTIONS ON THE K&N AIR FILTER CLEANER BOTTLE. IT IS RECOMMENDED TO UTILIZE K&N’S 32oz PUMP SPRAY CLEANER (P/N 99-0621) WHEN SERVICING LARGE OR DIESEL APPLICATION K&N AIR FILTERS.

Spray K&N Air Filter Cleaner onto both sides of the air filter until it completely saturates the pleated material.

A. Apply K&N Air Filter Cleaner to clean side of filter
B. Apply K&N Air Filter Cleaner to dirty side of filter

Allow cleaner to soak into both sides of air filter for 10 minutes to loosen the dirt. Do not let cleaner dry on air filter.

CAUTION: THE USE OF ANY OTHER CLEANING SOLUTION OR METHOD COULD DAMAGE THE FILTER!

2. RINSE

Rinse off air filter with cool low-pressure water. Allow gravity to flush dirt out of air filter by applying water to the clean side of the filter; up and down the length of the pleats.

Continue to rinse the filter until all traces of cleaner are gone. If the filter is extremely dirty it may be necessary to repeat steps 1 and 2. If there are spots of dirt remaining on the filter, spray each spot directly with cleaner, allow a few minutes for it to soak and repeat rinsing step.

3. DRY

After rinsing, gently shake off excess water and allow filter to dry naturally. Do not proceed to the oiling step until the filter is completely dry.

CAUTION: THE USE OF ANY OTHER DRYING METHODS (I.E. COMPRESSED AIR, DRYER HEATERS, HEAT GUNS) COULD DAMAGE FILTER.

4. OILING

RECOMMENDATION: FOR BEST RESULTS USE K&N AIR FILTER OIL.

Apply K&N Air Filter Oil liberally to the dirty side of the filter only. This will allow for a visual reference of complete coverage.

A. If using a K&N squeeze bottle, squeeze bead of oil along the crown of each pleat using the lip on the squeeze bottle tip as a guide. Utilize graduated view strip on bottle to dispense proper amount of oil.

B. If using a K&N aerosol spray, spray an even amount of oil along the crown of each pleat.

Wait 20 minutes for the oil to be absorbed into the filter media. Inspect the clean side of the filter for any areas that are lighter in color. Touch up these areas in the media by applying oil to the dirty side of the filter. Continue oiling procedure until there is an even red color over the entire surface of the clean and dirty side of filter.

5. FILTER INSTALLATION

Before reinstalling filter back into vehicle, inspect it for damage. Follow any and all specific installation instructions that came with the K&N Air Filter.

[brain_rinse]

Doc, that would make sense. I agree 500 hours seems too long. I'd stick with the manual's 100 maintenance interval.

[squeeg333]

Well, whatever the case, I know mine is fairly dirty. I'll need to clean it for sure before this year gets started. I'm assuming they still call it a flame arrestor, but in actuality it's more of a glorified air filter than anything on the EFI engines.

[dru1974]

well can you get the k&n for the 325 hp ? I would buy them I wonder if you would get any gains in hp thanks docdrs

[DOCDRS]

If your metal flame arrestor is anything like the one on my 310 i doubt a K&N would improve performance. when i ran water thru it there was very little impedance.

[newty]

I'd never thought about this before but while Mmandley and I were standing around finishing off a 12er talking about this thread, I pulled mine off. I've got just under 150hrs and it was pretty nasty. I sprayed it down with some carb cleaner and breathed really heavy to help out my buzz.;) Cleaned right up. I could hardly see any light through it before I cleaned it. I would imagine it would cause problems if over looked.

[Razzman]

So i'll weigh in on this topic. First only the 340 cat has the K&N and yes you can get a retrofit kit from K&N that will work on the 325 but it is a generic round auto style assembly, not the cone style the 340 has. That requires a special intake which does not work on the 325.

You will not gain any performance as there is no restriction to begin with like an auto application. What you will gain is the filtering of the air, period. BUT that isn't really an issue on these boats as they are not in direct contact with airflow.

Having used K&N filters on every maotorcycle and car i've had i'll give you the short version to service which works just fine. Wash it with approved cleaner, let it dry. Using the spray oil lightly spray until all the pleats are red. That's it.

Btw they actually work better the dirtier they are filtering out particles smaller than 5 microns without any reduction in airflow, hence the reason they have a million mile warrenty.