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View Full Version : Out with the rubber-hose-to-the-ear trick.....



09-12-2006, 06:42 AM
For years I have been using a rubber hose pressed to my ear to listen to engine noises, thinking I could listen for potential problems or unusual sounds to help me diagnose engine malfunctions. That is, till I broke down and purchased a NAPA Mechanic's Stethoscope . Whoa! Was I listening in the wind. This little jewel picks up sounds that I never heard before! I can hear valves opening and closing, rockers rocking, water pumps pumping, and all kinds of other music to my ears. The loudest part of my engine is my darn Delco-style alternator. What a racket! Gotta be some bearings trying to go out. Grinding noise that don't sound good. Back to Autozone. (Is there a better quality alternator out there?)

My wife thinks I am nuts, scrunched over the engine with this thing stuck in my ears, playing doctor....


Bill

Tomster
09-12-2006, 08:53 AM
Playing ??????

bobh
09-12-2006, 08:58 AM
Bill,
No wonder you have had so many problems with your engine! The rubber hose is for listening to carburetors. An old method to try and syncronize multi carbs by comparing the sound of the incoming air.
I use a hardwood dowel to listen to the inside of the engine. Same principle, touch the dowel on the valve cover, hold it tight in your hand and either push one of your knuckles against the area behind your ear (where the temple of your glasses sit) or hold it up close to your ear.
The stethoscope is definitely uptown. With all the gadgets you've concocted to work on your car I expected you to have a home made stethoscope. Maybe some vaccuum tubing attached to an old pushrod. Or a set of dentures clamped to a stud with surgical tubing running to your ear?

Musicman
09-12-2006, 09:03 AM
A nice long hefty screwdriver works good, too.

Geo Hahn
09-12-2006, 09:15 AM
I have a stethoscope I use to listen in on things... a lot of racket from the distributor is pretty normal I think.

Even at idle those points are opening up and slamming shut 30 times per second.

martx-5
09-12-2006, 09:21 AM
[ QUOTE ]
... The loudest part of my engine is my darn Delco-style alternator. What a racket! Gotta be some bearings trying to go out. Grinding noise that don't sound good. Back to Autozone. (Is there a better quality alternator out there?)


Bill

[/ QUOTE ]

The Delco 10 SI is a very good alternator...pretty much bullet proof. Everything depends on the rebuilder. If they don't put quality bearings in there, they won't last. There's alot of suspect Chinese 6203 bearings out there. Some of them make noise right out of the box. The difference between a cheap 6203 bearing and a good one is about 25 cents. It may not sound like alot, but if you're using thousands a day, it adds up quickly. At our place, we've been burned once, and now just suck up the extra cost.


/ubbthreads/images/graemlins/driving.gif

swift6
09-12-2006, 09:25 AM
[ QUOTE ]
Maybe some vaccuum tubing attached to an old pushrod. Or a set of dentures clamped to a stud with surgical tubing running to your ear?

[/ QUOTE ]

/ubbthreads/images/graemlins/lol.gif That would be awesome.

/ubbthreads/images/graemlins/cheers.gif

R6MGS
09-12-2006, 02:34 PM
[ QUOTE ]
Bill,
No wonder you have had so many problems with your engine! The rubber hose is for listening to carburetors. An old method to try and syncronize multi carbs by comparing the sound of the incoming air.
I use a hardwood dowel to listen to the inside of the engine. Same principle, touch the dowel on the valve cover, hold it tight in your hand and either push one of your knuckles against the area behind your ear (where the temple of your glasses sit) or hold it up close to your ear.
The stethoscope is definitely uptown. With all the gadgets you've concocted to work on your car I expected you to have a home made stethoscope. Maybe some vaccuum tubing attached to an old pushrod. Or a set of dentures clamped to a stud with surgical tubing running to your ear?

[/ QUOTE ]

I bought a proper S.U carb syncronizer a year ago....It works great...but I still fall back on the old hose to the ear as well...It's good to get two opinions /ubbthreads/images/graemlins/jester.gif

kc_doyle
09-12-2006, 03:42 PM
"a second opinion" That's what my Dr said when he used two fingers for my procto exam.

Musicman
09-12-2006, 05:05 PM
OUCH!!!

Banjo
09-12-2006, 07:19 PM
I always used my big Craftsman screwdriver. It's long, and has a ball that rests agenst my ear nicely. But I also have a stethoscope, and I have to say it works wonders.
Another really neat device we have at work is what they call "chassis ears" YOu have long wire leads with spring clips on the end that you can clip to various parts of the car. I.E. a hub of a suspect wheel bearing. and they connect to a box that has a switch to let you listen to each "channel" sepratly through a set of headphones. That way you can drive down the road and it sounds just like you have your stethoscope on wherever you clipped the leads.
Extremely handy for isolating a bad wheel bearings, squeaks, or other drivetrain noises that only occour at speed.
They are available through tool catalogs for around $150, but I've been meaning to see if I can build one. If I do, I'll post the plans for you guys.