mt_goat

Start looking for other sources with one of these ($12 at NAPA):



I'd probably start with the fan bracket bearing (fake water pump). Probably easier to check with the fan blades removed first.

sb5walker

I question the wisdom of not replacing the lower idler - in my experience, especially lately, that goes quicker than the upper. It almost certainly will not last for two full changes of the belt (120-140k miles) And it's cheaper and very easy to replace (once you're in there at the belt). But, assuming the shop is not completely incompetent and did verify that the idler is (at the moment) okay, then, yes, a mechanics stethoscope is the tool which will enable you to identify what's squealing. Could be alternator or A/C idler, if not P/S pump or fan bracket.

BUT BE CAREFUL. Make absolutely sure you do not have any loose clothing or hair when you're working near the belts of a running motor. It's very easy for something loose to get caught up in the belts, and you don't want your face to be violently drawn into the fan or some such. I once saw a cat that got caught in a belt of my father's Suburban - the animal apparently was sleeping on the warm engine and when it was started, it tried to escape. Not a pretty sight.

Just carefully place the rod of the stethoscope against the non-moving portion of what you're checking, close to the bearing. You'll hear some bearing noise from everything, but if the bearing is bad the noise is loud and awful.

mt_goat

Yeah I have also seen a cat mauling by engine, not a pretty sight but the sound was even worse.

TNRabbit

GREAT advice on keeping clear of moving parts. I've seen cats skinned alive by running engines/belts. My Dad was a mechanic & had a finger run ALL THE WAY around a pulley when I was a kid...you only let that happen ONCE.

kinda like the first time I stuck my finger in a R/C plane prop-- @ 14,000 rpm, it'll hit you 500 times before you can even MOVE~

norcal707

I would like to see a pic of the truck we are talking about to see how much rust you have

Gravely_Man

Hello,
I appreciate the suggestion on the stethoscope. That is the way I determined the noise was coming from behind the timing belt cover. That and I unhooked the other belts to see if the noise went away and it didn’t.

I am just concerned that the noise was thought to be a timing belt idler or the water pump from three different shops and now find out that was not the cause. I have not a clue how to trouble shoot this issue any further as this is beyond my mechanical knowledge now. Driving a truck that has a loud whine to it is not very comforting. I keep wondering if I will make my destination each time I drive it now.

Thank you,
Gravely_Man

TNRabbit

GM: where are you? If nearby to one of us maybe we can assist.

Gravely_Man

TNRabbit,
That would be most welcomed if anyone could lend an ear to try and find out what the real issue is. I am located outside of Cleveland, OH.

Thank you,
Gravely_Man

Gravely_Man

Does anyone have any ideas on what else I can check to try and narrow this noise down? Any and all suggestions are greatly appreciated.



Have a great day,
Gravely_Man

TNRabbit

Is it possible to record the sound & post up here?

sb5walker

Also check out the base of the distrib with that stetho. Sometimes the fuel pressure regulator will make a noise, tho not exactly like a squeal. That's the little can on the front of the drivers side fuel rail, with a short hose attached to the side and a little vac tube on top.

You did check the alternator with the stetho?

TNRabbit

Yep, they TICK like crazy

JBurt

I think it would help alot if you had something to record the noise (i.e. a voice recorder or a phone with that capability, or a digital camera with a mic) and post it up here. It's amazing how people really familiar with the engine can tell what wrong by the type of squeal. Good luck.

greaseball

i rebuilt mine in my man cave in the middle of winter and put bit together and in the truck myself with nuthing but the peanut gallery(wife and cats) helping next time i will use a cherry picker and wait awhile after carpel tunnel surgery i'm to old and stubburn just ask my wife.

greaseball

i rebuilt mine in my man cave in the winter the only help i had was the peanut gallery(wife and cats) next time i will wait for my carpel tunnel surgury to heal.i'm just to old and stubbern i guess but the truck runs and my wrist only hurts when it is cold out.