Automotive Stethoscope?

I bought one from NAPA for almost $40, but in all honesty, it realy doesnt work any better than attaching a metal rod to a 1/4-5/16" hose, and placing the hose in your ear, other than the fact you get to hear through both ears.

 

I got one for around $10 at the local AutoZone. It has a diaphram where the test rod attaches which I think gives some amplification to the sound. It seems to do a good job.

 

Yup, mines has that diaphram bulb too, but its still no better than the hose in your ear trick.

 

We used to just use a broom handle. Place the wooden end on any part of the engine and hold handle with your right hand. Press the knuckle of your thumb hard on the tragus (flap over the ear canal) and listen. Don't laugh...try it.