Screeching From Front Of Engine?

Would that be the water pump or alternator?

stock 35amp mototorla alt on a dauntless v6. Alt dummy light in speedo doesn’t light.

no leaks I’ve noticed. Belt is tight and the pulleys aren’t warm on either the pump or alt to indicate belt is slipping.

It’s intermittent but happens often when idling. Increases as RPM increases but still isn’t constant.

drove it all day yesterday with no issues. Started it up this afternoon after church and it started before I got out of the garage.

thoughts?

 

I would suspect the alternator bearings first. Usually the water pump starts leaking when it's bearing is bad.

 

At least that would be easier to replace

 

X2, check your water pump for leakage at the weep hole, and see if you can detect any loose movement in the brg by taking hold of the fan blades.
If the alternator is the problem, the bearings can be replaced. I bought bearings for my Ford truck alternator at napa. Went by the bearing number(timkin) rather than asking for a bearing for my alternator.

 

Run the engine without any belt for 20-30 seconds max. Rev it some during this period.
That way you can rule out any internal engine component...assuming it stays quiet.
Better yet, get a mechanics stethoscope. These are handy to have and inexpensive. You can probably find one at your FLAPS.
Performance Tool W80582 Performance Tool Automotive Stethoscopes | Summit Racing

 

Yes.

Or a wood dowel, or a long screwdriver. Put one end to your ear, and touch the other end to the various bearings and such. The source of the problem will be obvious.

Do NOT stick it into the fan or any other moving parts, or you'll have a worse problem.


Does this engine have a thermal fan clutch?

 

that’s funny you mentioned using the long dowel or screwdriver. My grandpa showed me that when I was looking for my first car as a kid. I had forgotten all about that!

the engine does not have a thermal fan clutch.

 

What are you trying to imply???

 

As above, the alternator is likely the prime suspect. If you aren't going 100% stock, time for a Delco 10SI or 12SI. Reminds me of an issue with one of the work trucks many moons ago. A 1988 Chevy 2500 that only had a few thousand miles on it at that time. The screech was a singular event, immediately followed by a large bang. Pulled over to find the alternator was literally in pieces, on fire, and no fan belt. Oh, and a dent in the hood. That was GM's small body alternator. We were a number of miles from any habitation so I ended up letting the engine cool, then driving a mile or two until it got too warm and sitting again. Repeated a number of times before we got to a bar where we hitched a ride to the next town for a replacement and hitched a ride back. Cell phones are kind of nice-------

 

did this with a long screwdriver

the sound was coming from the alternator.

then I did this to confirm there wasn’t an internal engine noise.

no noises.

after taking the belt off I can hear the noise in the alternator by manually spinning the pulley.

thanks for the suggestions on confirming the issue

-Dale

 

Living in Ft Worth Texas in the late eighties driving a local delivery truck. The truck had a noise coming from under the hood when driving but when raise the hood noise went away. I got back in the truck and headed to the next stop on a local two lane highway and boom and a dent popped up on the hood and dash went dim. Pulled over and opened the hood, and found one of the blades on the fan came off and sliced into the battery and hit the hood. Long before cell phones were common. Can’t remember how I got back to the shop. But was quite a noise.

 

Considering going the 10si route for the alternator replacement. Also considering having my Motorola 35amp rebuilt.

Been researching and I’ve seen that the 10si doesn’t charge at “low RPMs”. How low is low?

Had the Motorola tested and it still “passes” at the flaps, but the bearings are shot.

thoughts?

 

That’s what I’m thinking. I like original equipment.

 

Putting in alternator bearings is an easy task. Maybe $20 in bearings.

 

Do you have to have a press or anything special to install them?

 

The 10si doesn't kick in when you first start the engine until you rev up to about 1000-1200 on the dauntless. BUT After that it stays charging even when idling. It just needs and initial kick of rpm to wake it up, then it is good to go.

The 10si is a much better system than the motorola IMHO.

 

A small puller, a short piece of pipe and a hammer would do it. Make sure to apply pressure only on the inside of the bearing.