High Pitched Noise

[Alan]

I have a 89 Senator with a 330hp 454, Bravo 1, thru hull exhaust. At mid range speeds I hear a high pitched noise, almost like a slipping fan belt. Any one have any idea as what it could be?

[Alan]

I have a 89 Senator with a 330hp 454, Bravo 1, thru hull exhaust. At mid range speeds I hear a high pitched noise, almost like a slipping fan belt. Any one have any idea as what it could be?

[vinny p.]

Do you notice a change of pitch when you turn the wheel? If so, the noise would most likely be caused by a bad gimbal bearing.

[fastskipper]

Had a noise like that once....The regulator on the alt. went nuts and was over charging.

[Eriktheviking]

My 87 454 Senator did the same thing and it was the belts.I replaced them with heavy duty versions ,adjusted to the proper tension and I was all set. http://checkmate-boats.com/6/ws/,s,8626072361/Graemlins/biggthumpup.gifI'll bet there is a bunch of rubber filings all over your engine compartment. Make sure you clean out your spark arrestor, I'll bet it's clogged up with filings too.

[Alan]

Thanks for the reply.I did change all the belts, no difference in the noise. I thought it might be a resonance from the exhaust. It had 3" went to 4" no change. The gimbal was my last guess. You do not notice it at slow speeds or at hight speeds just at mid range. When I get it in the water this summer, I will see if it makes a difference when turning. How about gear wine or motor alignment issue?

[Eriktheviking]

When my gimble went you could hear a rumbly sound that would get more pronounced when I would turn.I didn't hear at mid or high end ,only at low speeds.Its certainly possible that it could be that but I don't think the noise would go away at high speeds.Do you smell anything burning after your stop? Heres Something that happened on my Enforcer when I first bought it. The steering cable was so stiff (hard to turn) that it kept the actuator for the power steering on most of the time and it would chew up steering belts because the pump was having to work most of the time http://checkmate-boats.com/6/ws/,s,8626072361/Graemlins/jpshakehead.gif.Good Luck

[Redboat]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Alan:
I have a 89 Senator with a 330hp 454, Bravo 1, thru hull exhaust. At mid range speeds I hear a high pitched noise, almost like a slipping fan belt. Any one have any idea as what it could be? <HR></BLOCKQUOTE>
I have the same boat with the same problem , did you find out what it is ? I replaced the gimbell bearing with no change .

[Alan]

No I haven't. I was planing on doing the gimbal but will wait. What prop are you using? I have a mirage 23, could it be possible it's the prop? I thought it could be the air rushing over the hull creating the noise! It may be going on at high speeds but my exhaust might be drowning it out. Alan

[Redboat]

I run a Mirage Plus 14.25x26 . Ditto on the exhaust drowning it out .

[Alan]

Redboat, I had a mirage 25" and could only turn it 42, 4400 rpm then went to the 23 mirage. It runs about 4600 rpm 64 mph on gps. I was thinking about trying a Bravo 1 22 pitch only because I would like a better hole shot. Have you have any other experiences with props?

[Redboat]

Alan , I tried a bunch of props , 3 blades , choppers , even the 5 blade ( this one will snap your neck on takeoff , but no top end ) . I have the mirage plus on most of the time , runs 4400 to 4800 rpm at 68 mph gps and a mirage 14.25x19 for waterskiing and pull toys .Really have to watch rpms with the 19 .