How I made my M25XP quiet.

Aug 26, 2013
24
Catalina 30 MKII Horseshoe Bay
After a few trips on my Catalina 30 wishing, hoping and praying there would be good wind, there was not. Day after day I was going to have to listen to the obnoxious drum of my engine. The factory air cleaner was nothing more than a tin can with some holes in it and what looked like course steel wool. Having a friend with a Kubota tractor 24.5 horsepower and hearing how much quieter it was I decided to make the air cleaner from that model tractor work. The improvement was dramatic! In the photos I have attached you can see it fits nicely. I have put 20-25 hours on the motor since doing the job. Fuel economy remains the same as well as power. noise reduction is dramatic. When the engine is at idle I can go into the cabin and hear the fuel pump ticking away now!
From the parts diagram I used 001 (complete air cleaner assembly)
009 (intake hose which was cut down)
010 x2 clamps
 

Attachments

Feb 5, 2004
3,727
Tartan 3800 Westport, MA
Thanks very much! I'm having a bit of difficulty visualizing it from your pics - does it go through the rubber pipe and then aft? What's the muffler housing attached to?
 
Aug 26, 2013
24
Catalina 30 MKII Horseshoe Bay
Yes. The intake hose goes back ad the intake air cleaner is located above the transmission tucked up into the starboard corner
 
Feb 8, 2007
141
Catalina 36 MKII Pensacola Beach, FL
I have a 1996 Catalina 36 MKII with an M30, or maybe an M35??

My engine seems to be very loud compared to other boats I hear.

Would something like this work for me?
 
Feb 26, 2008
600
Catalina 30 Marathon, FL
Aaron,
It looks like you've also added some kind of sound proofing material to the engine compartment. What did you use?

I was amazed at the difference new motor mounts made. I'd love to quiet down my engine down even more.

Jim
 
Jun 5, 2004
241
Catalina 30 MkII Foss Harbor Marina, Tacoma, WA
...you guys just added a project to my fall list. I do believe our boats to be a bit louder than most.
Thanks
 
Aug 26, 2013
24
Catalina 30 MKII Horseshoe Bay
I have a 1996 Catalina 36 MKII with an M30, or maybe an M35??

My engine seems to be very loud compared to other boats I hear.

Would something like this work for me?
If you have the room, I dont see why not. Being that you have a higher power engine, you may want to source from a slightly bigger tractor made by Kubota...
 
Aug 26, 2013
24
Catalina 30 MKII Horseshoe Bay
Aaron,
It looks like you've also added some kind of sound proofing material to the engine compartment. What did you use?

I was amazed at the difference new motor mounts made. I'd love to quiet down my engine down even more.

Jim
The boat already had the sound deadening when I got it. It is pretty thick, near 3/4". Yes, I have had softer mounts installed too. Much easier on the fillings!
 
Aug 26, 2013
24
Catalina 30 MKII Horseshoe Bay
...you guys just added a project to my fall list. I do believe our boats to be a bit louder than most.
Thanks
I just did a trip which unfortunately turned into an all motor trip. Not a spot of wind. I found after making the engine much quieter that it became a lot less fatiguing on a longer trip...
 
Feb 26, 2004
20,692
Catalina 34 224 Maple Bay, BC, Canada
Why Knot?

I absolutely REFUSE to do this!

If I can't feel that beast RUMBLING beneath my feet, so I can find out if the damn coupling threw yet another bolt, I don't want that engine.

Rumble, rumble, tank, tank...:eek::eek::eek:
 
Aug 26, 2013
24
Catalina 30 MKII Horseshoe Bay
I absolutely REFUSE to do this!

If I can't feel that beast RUMBLING beneath my feet, so I can find out if the damn coupling threw yet another bolt, I don't want that engine.

Rumble, rumble, tank, tank...:eek::eek::eek:
Quite the contrary Stu. The quieter engine does a great job feeding my paranoia... It leaves my ears to hear all sorts of disastrous noises that really arent anything!
 
Feb 26, 2008
600
Catalina 30 Marathon, FL
Aaron,
Just circling back to this as I ponder winter projects. This one definitely made the list.

Thanks for posting it.

Jim
 
Aug 26, 2013
24
Catalina 30 MKII Horseshoe Bay
Aaron,
Just circling back to this as I ponder winter projects. This one definitely made the list.

Thanks for posting it.

Jim
I would have done a video clip trying to show the noise difference, but I don't think it would do justice. I am sure you won't be disappointed! Having already had sound deadening put in and soft engine mounts, there would only be one place left for noise. The engine is now so much quieter, during cruise speed especially (2500rpm) that if I go inside I can hear the electric lift pump ticking away... :)
 
Oct 13, 2011
13
Catalina 30 MkII Lake Murray, SC
So you just took a section of hose and attached it to the engine where the air filter is normally attached. Then you hooked the new air filter to the other end of hose and routed it out of the way. So the new air filter is some distance 18" to 25" from the engine. My air filter has nothing inside of it. Let me know if this is correct. Thanks for the idea !
 
Aug 26, 2013
24
Catalina 30 MKII Horseshoe Bay
So you just took a section of hose and attached it to the engine where the air filter is normally attached. Then you hooked the new air filter to the other end of hose and routed it out of the way. So the new air filter is some distance 18" to 25" from the engine. My air filter has nothing inside of it. Let me know if this is correct. Thanks for the idea !
That's exactly what I did. The air cleaner from the kubota L245 is fairly compact and quiet.