Whining sound from motor

[Gene Fiore]

My motor is making a growling/whining sound. I do not have a/c or p/s so it's either the water pump or alternator...I think. If I disconnect the fan belt the sound goes away. Is it likely to be the water pump or alternator?

 

[Bort62]

Use the stethoscope trick and find out.

 

[64falconsix]

have the alternator bench tested at the auto parts place. if its the problem it will make noise when they test it.

 

[CobraSix]

It's usually the alternator, but like quicker said, take it to a parts store for a free bench test. It'll solve the mystery usually right up.

 

[Bort62]

Stehoscope will solve it in 5 seconds w/o taking anything apart.

 

[Gene Fiore]

Stehoscope will solve it in 5 seconds w/o taking anything apart.

Please edumacate me...how do you do the stethoscope thing?

 

[fordconvert]

There are real things called mechanics stethoscopes, they pretty much look just a doctors except there is a rod on the end of the pad thing they normally put on your skin. It works the same way, sound goes through the rod into the pickup thing and then is transmitted through hoses to your ears. You can often do the same thing with a long screwdriver or a broom stick. You touch one end to the thing you suspect is the problem then check other things in the area to get an idea what is normal and what is a problem. You stick the other (big) end on your ear. Also something like a hose or piece of pipe sometimes helps to narrow down where a sound is coming from. Always think and plan your moves before you use any of those tools on a running engine, you will be close to lots of moving parts and can get into serious trouble real quick! The real mechanics piece has an advantage for safety because you can be looking at the probe, the other methods require you to turn your head to point your ear in the right direction so you cant see where you are sticking things.

http://www.harborfreight.com/cpi/ctaf/d ... mber=41966

Should be a fairly common tool available in better parts stores.

 

[fordconvert]

Forgot to add, without the belt on you should be able to spin the fan (waterpump) and the alternator and listen for the same sort of noise. Without the rest of the noise of the motor running it may be easy to tell.

 

[wallaka]

I use a long screwdriver or extension for a stethoscope. One end on my ear, other end on the engine. Works pretty well.

 

[Bort62]

I have one of the special ones, but a bolt stuck in a peice of vac line works pretty well too.

Like stated above, listed around the area and it should allow you to pinpoint the noise.

 

[Gene Fiore]

Thanks guys...I'll try the stethoscope trick and see what I find.

 

[jamyers]

If you've got the fan belt off, see if the waterpump or alternator spins smoothly - if not, there's your culprit.

If you put the belt back on, the 'stethoscope' is your friend.

 

[Gene Fiore]

Used a long steel rod as a stethoscope...it's the alternator. I then took it down to Auto Zone for them to test...just to make sure. As soon as they spun it up it started squealing like a stuck pig. Replaced it already and I'm good to go! Thanks for the help.

 

[Bort62]

No prob bob.

Er, Gene.

 

[yodabiri]

Ah a happy ending!