Engine noise - sort of like belt whine
 

Hello all - hope you can help. Have an '86 CC Stinger. Port side engine when started cold/warm makes a sort of squealing sound. It sounds a lot like a belt whine. There is one belt on this engine going to the alternator. I've soaped the belt to see if it was the cause of the problem, but it did not change the squealing at all. Once the engine has warmed up, the noise goes away and everything else seems fine. I've tried to listen to where the sound is coming from, and it sounds like in the engine itself, i.e. not the alternator or belt. Any ideas as to what this might be? With the end of the season coming, I want to get my winter plans lined up r.e. work on the boat.

thanks!

Its hard to tell from here. But take a look to see if that side circ pump has been dripping water from the weep hole on its snout. That noise I think is different from a whine but if bearings been getting wet it will make some type of noise. Also alt belts will wear out the side surface and ride deeper in the groove and will whine like your describing. You could try to put a small hose to your ear and can focus on different parts of motor.
Jim

do you have blowers?:party-smiley-048:

NEVER SOAP YOUR BELTS!!!

Not even for a test! The other guy said they ride deeper and that is correct. Look at the side of the belt and see if it is shiny and check for small cracks. Do this by bending the belt a bit in the centre section somewhere.

There are sprays available from Auto Jobbers that will stop squeal but it is just better to change it. The squeeling is an indication of wear and it is telling you "I need changing" , not soap on it or fancy sprays, as this only belabours the problem, and you don't want to be five miles offshore and the thing breaks on you!

Thanks for all of the advice. I do not have blowers on the motor. I only soaped the belts a tiny bit to see if it made any difference in the sound itself - but it did not. Next, I think I will take the belt off and replace it to see if it makes a difference. Probably this next weekend coming up.

It was mentioned to me that this might be a bearing inside the engine. Not sure what that would sound like, but after researching on the internet I don't think that would be it. Wondered what exactly a bearing going in the engine might sound like.

thanks again.

Try running momentarily without the belts installed. If the noise does not occur in this configuration, then something belt driven is the source. Water pump bearing, alternator bearing, tensioner, etc.

Greg

It might be a water pump??? At cold start the bushing inside the pump my have a bit of play. When it warms up it may expand just enough to stop squeeling??? This is only a thought.
I also agree with the person who said to remove the belts for a short test. That would help isolate the problem.
If you have a mechanics stethoscope, that would also help. It looks just like a doctors, just that is has a long probe on the end to touch to parts on the engine. They work GREAT!!!!
Costs only a few bucks at any auto parts store.

Well, it turns out it was the belt - whew! The old belt looked ok, but it was a lot thinner than the new belt I got to replace it (same number.) Thanks for the help.