how to locate whining sound?

[natwales]

There is a whine that seems to be coming from the pulley system on the forward part of my engine. I only really hear it at idle but I suspect thats due to reduced engine noise. It's not the sound of a slipping belt - I don't think. It really sounds more like a corroded bearing of some sort either in my circulation pump or else where. There is no play or movement in any of the pulleys. I've tried listening with the engine running and it's impossible to tell where it's coming from. What's the best way to go about this?

After double checking proper belt tension My plan is to...

1) remove the power steering pump belt and see if sound goes away Otherwise...

2) remove the altenator belt (this won't hurt anything right?) and see if sound goes away. Otherwise...

3) replace circulation pump (< year old) and see if sound goes away..

Otherwise??

Is there somthing here maybe that I am overlooking that could make this sort of sound? It's definitely a reciporical sort of squeaky whinning. I really do suspect that it's my circulation pump. If so, could water intrusion really have corrode out the bearings in less than a year? Would over tension to the belts cause this issue?

Appreciate any help available.

 

[natwales]

Re: how to locate whining sound?

I don't know if it matters, but I should also add:

5.7L merc. 1988.

 

[Bondo]

Re: how to locate whining sound?

Remove the Belts,+ Spin the pullies by Hand......

You should be able to Feel/ Hear the 1 that has an Issue.......

My 1st Guess would be the Alt. Bearings..............

 

[bjcsc]

Re: how to locate whining sound?

I was thinking I usually find her in the kitchen... But then I realized this thread was about something else...

 

[NoWorries]

Re: how to locate whining sound?

You replaced the circulating pump a year ago....did you replace with automotive pump or a marine pump? If you have a raw water cooled engine and an automotive pump, then yes it could very well be shot in less than a year.

After noticing occasional sqeaky belts, I found my problem was a leaking hose from the circulating pump to the thermostat housing that was dripping on the belts. I checked belt tension repeatedly, but until I ran the boat while looking at the engine, I never noticed the small, small leak.

 

[Scaaty]

Re: how to locate whining sound?

8)8)8)

quote time=1152983647 user=bjcsc uid=76236 fid=24 tid= rid=3]I was thinking I usually find her in the kitchen... But then I realized this thread was about something else...[/quote]

 

[Boomyal]

Re: how to locate whining sound?

I was thinking I usually find her in the kitchen... But then I realized this thread was about something else...

 

[natwales]

Re: how to locate whining sound?

So I took off all belts and spun each pulley by hand. The circ pump (yes, marine and yes raw water), altenator, and power steering all spun very freely with no play or binding of any sort.

I double checked the tightness on all belts and they seem fine. I have noticed that sometimes during the first 30 seconds or so on a cold start the squeaking is absent, otherwise it's relentless. I have observed very carefully and there is no water leaking on to the belts. The condition of the belts is fine. I tried listening with a flexible hose and I feel like there really is a constant reciporical sqeaking coming from the drive pulley, but it's really hard to tell. Haven't I ruled out all of the other components anyway?

I'm Not sure where to go next, and I'd really appreciate any suggestions.

 

[wvit1001]

Re: how to locate whining sound?

While your idling the engine and you can hear the whining take a large screwdriver of a wooden dowl and hold one end firmly against the various parts you think might be making the noise. Put the other end firmly against your ear. You should be able to clearly hear if a bearing or other noise is coming from that part.

Watch out for loose clothing or other parts of your body getting caught up in the belts.

 

[Reel Poor]

Re: how to locate whining sound?

One of these is a necessary tool to add to your tool box.

Mechanics Stethoscope

 

[natwales]

Re: how to locate whining sound?

Well, I think I have eliminated the whine coming from altenator, circ pump, and power steering pump. If the belts are tight, then aren't I looking at somthing in the crank shaft pulley? Does that have a bearing that can rust out?