Air cleaner/silencer

[sail4dale]

Happen to notice that the foam is just about rotted out on my
engine air intake and wondered ...
what and where is the best source for a replacement.
It is the 35B engine.

[Roc]

I purchased one from this site just this week.  I pooled other spare parts together and got free shipping.

http://www.marinepartssource.com/details.asp?pnumber=UJHW301049

[Mike and Joanne Stimmler]

It might be worth a shot to take the old one to an auto parts store to see if they can duplicate it.

[Ron Hill]

Dale : I wrote an article on that foam "muffler" topic in the Mainsheet tech notes (1995?) !!

The bottom line was that you can pay $18+ for a piece of FOAM from Universal parts, or for 50 cents you can buy enough 1/2" foam at any fabric store to last your life time - and make your own.  Difficult to sew on a sewing machine, but not impossible.

A thought.  

[hump180]

Another option is to upgrade to a K&N filter. Many of us have changed over and there is a lot of info on it here in the messages. These filters can be cleaned and re-oiled and have better air flow than many filters. Here is a link (which contains some other informative links)and a photo of the unit on a universal. http://c34.org/bbs/index.php/topic,4873.0.html

[Ken Juul]

What is the purpose of the foam?  The foam is not there to keep the engine clean, but to help silence the air intake.  The boat is away from dirt sources most of it's life (on the water) and the intake air is sucked from the cabin or through the stern vents.  Any dust in the air should settle out well before it reaches the intake.  K&Ns look great, but I think I will spend my boat bucks other places.  I change my muffler every couple years.  Have a sheet of foam in the garage, cut a piece the right length and whip stitch the ends togther to make the donut.  Takes all of 10 minutes.

[John Sheehan]

On our M-35B I noticed the metallic material inside the factory air filter was starting to shed and come loose.  Universal said they hadn't heard of that happening but it does.  Because of the metallic pieces coming loose I replaced the original filter with the K&N and am pleased.  Have not noticed any increase in noise with the K&N.  Just check and be sure your factory filter is not shedding before you worry about the foam.

[prh77]

I am all for the K&N filter. The metal inside my 1988 stock filter started to come apart.....you can imagine the outcome.

[cmainprize]

John S
Do you happen to remember the part number for the K&N.  I have  an m35a but I bet they are the same.

Cory

[John Sheehan]

Cory,

We are up in Colorado visiting kids/grandkids so am not near the boat.  However I believe it was the K&N RU-2450.

John

[cmainprize]

Thanks John
Good Memory
The filter fits perfect.

Cory

[SeaFever]

Guys,

I have the metal air filter with the metal mesh inside on my M25.
Any pros and cons of this one?
Any suggestions on modification, such as putting the 1/2" foam inside on the wire mesh?
Has anyone done the modification on this type of air filter to connect the oil breather tube to the air intake? If yes, some pictures would be very helpful.

Thanks.

[David Sanner]

I believe that metal cover / cowling is a silencer.

The Beta Marine marine version of our Kubota block
has a very nice paper filter covered with a similar
silencer.  The tune the silencer based on the length
of the pipe section. It is just one of the reasons the Beta
Marine is so quiet.  (the heavy cast aluminum oil pan and
integrated heat exchanger mounted on the exhaust
also help)

[SeaFever]

Thanks David, that is very helpful. I will check with Beta Marine on the paper filter.

Has anyone modified this version of silencer/air filter to connect the breather tube? I can think of a few ways to do it, however it would be great if some people have already tried it. I can then gain from their experience.

[Ken Juul]

I picked up a  brass 90° fitting the correct size to fit the breather tube.  Drilled a hole in the top of the filter, inserted one leg of the fitting and screwed on a jam nut.  Attached the breather hose to the other side.  Brass fittings usually have pipe threads.  You have to get creative with your jam nut.  Either use a flair fitting nut with some washers to take up the space or find a brass nut that is the correct size and cross thread it on.  I chose the cross thread method, the fitting isn't going to be removed and requires no strength to hold it in place.  I did use locktite just to be on the safe side.  Sorry no pictures.