Whine

Never having owned a supercharged car before, is it normal for the blower to sound like a mildly grumbling P/S pump at idle?

If it sounds like marbles in a can, it's a worn coupler. Fairly easy to replace on the 96-99.

No marbles yet, but is a low level whine normal at idle?

Are you sure it's the blower? I had a failing alternator make a whining sound when the car had around 35k miles.

Check the oil level in the blower - should be at thread level.

skatterbrane wrote:

No marbles yet, but is a low level whine normal at idle?

It depends. The way the Riv intake is set up, probably not. You might want to open you airbox and see if somebody removed or filled the intake muffler. You might simply have an air horn mis-installed and leaking. The air cleaner box might not be closed right; I've seen people not put the tabs in the slots before closing the wire latches (look real careful you'll get it no prob). Sound control would be one reason to make that airbox out of filled plastic instead of stamped metal.

One other thing -- when I installed Gatorback belts I got a discernible whine at idle. You got Gatorbacks or Polycogs? They whine all by themselves.

A little old-school checking might find your whine; a rubber hose (one end at your ear) might help pinpoint it, just be real real careful around the hot, rotating or otherwise hazardous parts. (it's all about the whine, 'bout the whine, no neckties...)

Albertj

I installed a new air filter and the box is stock and well secured. I will check the belts. If it is not the S/C then I am pretty sure it must be the P/S. I actually have an automotive stethoscope. I will investigate further tomorrow. By the answers I am getting, it seems that S/C don't whine at idle, so that really answers my question. I wanted to establish that first before I started a wild goose chase.

Gutting the air box is a popular mod with no downside unless you object to the supercharger whine. It's one of the first things I did, and I love the sound, but I only hear it when the engine is in boost, otherwise it is quiet. I agree with Aaron, and Albert, you might be hearing the alternator or belts.

It shouldn't whine at idle, but check that SC oil.

I will check the oil, but it was just changed by the person I bought it from about a month ago. (but based on the other work that shop has done it could be olive oil for all I know).

skatterbrane wrote:

I will check the oil, but it was just changed by the person I bought it from about a month ago. (but based on the other work that shop has done it could be olive oil for all I know).

Close... people jokingly call it whale oil, because of the marvelous (ahem) aroma.  However, according to Eaton, it's NYE 605, a proprietary synthetic.  See [THIS LINK] for the Rivperformance discussion on the topic and type "NYE 605" in the search box at [THIS LINK]  to see MSDS details.  A datasheet is [HERE]. The GM fluid/NYE 605 is a phosphate ester.  See [THIS OTHER LINK] for a nice description of what a phosphate ester is. One thing you'll learn there is why you should change and not just top up your SC oil (spoiler: the phosphate ester lubes have high detergency so abrasive particles don't settle out in the sump, rather they stay in suspension and hack at the components).  It's a good, quick read.

Albertj

Used SC oil is quite likely the worst thing I have ever smelled, other than decomposition.

Yeah it smells like CAB plastic, but STRONGER. I am leaning towards the alternator.

If the alternator bearings are failing, the unit may run hotter than parts of the engine surrounding it. Use an IR thermometer or just feel the alternator after running a while. Using the solid probe on your stethoscope should isolate the noise.

There's plenty of noises be it whine, grumble or rattle. These power plants are mature. Take a board and place it on components with a bearing. Put your ear to the board and listen.

Thanks Aaron, it WAS the alternator! I am just 500 miles shy of 50K. I went to the junk yard and pulled a weathered looking alternator from a junked out 96 and installed it, no more whine.

My original one looks like new so my engine compartment aesthetics went down a notch or two.

Although it was the alternator I've heard many 3800's with whiny power steering pumps, including my own. I've even tried a Lucas additive after flushing much of the fluid and never solved it, after hearing so many others do it (certainly they ALL can't be low on ps fluid) I've learned to live with it.

Well power steering pumps need to be replaced every once in a while. I thought it was P/S pump at first, but never having a supercharger before, I wanted to make sure it wasn't normal for a SC car first.

skatterbrane wrote:

Thanks Aaron, it WAS the alternator!  I am just 500 miles shy of 50K.  I went to the junk yard and pulled a weathered looking alternator from a junked out 96 and installed it, no more whine.

My original one looks like new so my engine compartment aesthetics went down a notch or two.

Scotchbrite wheel and compressed air cleanup... !!