OUTLAW EAGLE MANUFACTURING

DIGGINSWEATINSWEARIN · Joined: 02 Nov 2010 Posts: 47 Location: Deroche B.C.

I have a boat with a 240 SJ in it, its the only SJ that I have ever been around close enough to hear clearly. My question is regarding a high pitched noise it makes from about 3500 to 4000 rpm. Now I realize that SJ's are loud but in this narrow window of rpm it makes and ear bleeding howl, below 3500 its fine and above 4000 it sounds like every SJ i have heard in any posted video. Just wondering if anyone has had the same issue?
thanks, Darren

shallow draft · Posted: Sat May 12, 2012 10:27 am Post subject:

The are loud in stock form but the noise can be improved. Insulate the motor compartment for a start. The other success I had is to put a piece of rubber on the swim grid. This seemed to help a lot by absorbing some of the vibrations that translates to noise. I also opened up the brass water inlets to the exhaust to get more water in the exhaust system to also absorb the noise. I have reduced the noise to a level that is tolerable. It is still not as quiet as a 4 stroke but I can live with it now.

DIGGINSWEATINSWEARIN · Joined: 02 Nov 2010 Posts: 47 Location: Deroche B.C.

Thanks S.D. i wouldnt really be concerned if it was just loud all the time but it is just in a certain rpm range. I dont know maybe it is just a resonence (sp?) and there is no problem at all but when ever anyone hears that sound for the first time they look at me with very wide eyes, as if to say "what the hell was that?" Confused

shallowman · Joined: 03 Apr 2006 Posts: 199

Here is something that also can make a ton of noise ,
underneath the boat at the intake there is a piece of Aluim. which most people call a horse shoe it goes around the outside of the intake grate have a close look at it and make sure it is not making contact with the boat ( bottom )it must be be touching or you will get loud harmonics it is part of the pump assm. not the bottom of the boat
if it is touching just unscrew the bolts remove and grind back a 1/4 of a inche or until not touching the hull ,
you will be amazed at the noise that makes

let'er buck

Twisted Evil

sneddonrider · Joined: 05 Jul 2011 Posts: 31

My 05 bobcat with a 240 sport jet makes a high pitch electronic sound at certain rpm I was wondering if it was normal as well. I read that the 600 e tech sleds have voice coil injectors that make a high pitch sound and I think that the mercury two stroke motors are where skidoo got that technology.

mxracer68 · Joined: 19 Jun 2006 Posts: 38

Normal as far as I know. I had a 250 opti, same thing. I don't recall the RPM range, but there was a certain pitch that sounded similar to what you are explaining.