Mechanics stethoscope... solving a decades old mystery

[454cid]

Out of all my vehicles I've owned I've had my 69 Buick LeSabre the longest. It hasn't really been on the road much in the last few decades as it really needs work. I noticed early on, when I bought it, that while idling it had a sound that reminded me of water running through pipes, and I always figured it was the power steering system.... made sense to my early 20's self. A couple of days ago I was running the engine, and noticed how loud that water sound was again. The 430 in my Electra would purr (before it spun a bearing) so I was a bit disappointed on how loud the 350 in the LeSabre was sounding. That's when I realized I'm older, wiser (LOL, I know) and have many more tools inclusing a mechanics stethoscope. I actually have two, somehow, both from Harbor Freight.... They're great, go buy one if you don't have one.

So I start poking around the power steering pump, and it's making noise, but nothing that stood out as unusual. THEN, I checked the alternator..... it was so LOUD, it almost hurt my ears. Remember that "older, wiser" statement? Maybe it's just older... I can't believe it never occurred to me that the bearings had gone out in the alternator. So I've ordered a new rebuilt ACDelco alternator from Amazon, because I'm impatient, and also bearings for the original.

I considered going to an internally regulated alternator, but I already have a new electronic external regulator, and I like it mounted on the inner fender, where GM put it. I'd also rather not have the long wire running to it sitting unplugged.

 

[grampadirt]

Cool! Always nice to find an annoying noise.I have one of those stethoscopes and it has found a few annoying squeals and whurrs...handy tool to have.

You mentioned a 430....My first muscle car was '66 Buick Skylark GS,eventually I blew up the 401 in it and thought I'd just buy another one and replace it.Well while at the junk yard I came across a '67 Riviera with a 430 in it,car was totalled but the engine was fine.So with a little help I stuffed that 430 into that GS and had a very fast hot rod.....never lost a street drag again

 

[Scooterwrench]

Yeah man,that's a must have tool. I even use mine to listen to pocket watch escapements(ticks).

 

[someotherguy]

Give your new/rebuilt alternator a listen. They're loud, too! But it does sound like your old one probably needs bearings.

Richard