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Screaming alternator belt - 95 GSX

I have a problem that I'm hoping someone here can help out with.

My '95 GSX had a squeaking belt problem as soon as the weather started turning cold here in SW Pennsylvania. I decided that since I didn't know much about this vehicle's past maintenance history, I'd just put new belts on it. I heard lots of warnings about overtensioning the belts, so I put them on a bit sloppy. After some squealing started, I tightened the power steering and alternator belts (was squealing when I'd turn the wheel, and when there was a heavy load on the electrical system).

A week or so later, the squeal came back under electrical load. I checked the alternator belt, and it seemed loose again. I tightened it up some. Next week, same thing. Week after, same thing. I figured this was excessive for belt stretch.

A couple days ago, a loose rattle started coming from the engine compartment. I didn't know what this was, but I knew the squeal problem had gotten worse too. On a cold start, I'd have to keep lights and fan off, and on any return to idle, I'd have to turn the lights and fan back off to get the belt to catch again, and even that sometimes took a little while. While the belt squeal is happening, it is definately not charging at all.

I figured the alternator was probably going bad because the squealing stopped when the load was removed from it. However, I pulled the belt back off and spun the alternator - it spun freely, seemingly no resistance, no shaft freeplay. I then noticed where all of the belt residue was collecting - the motor mount. I spun the water pump, and it made a bit of a grinding sound, though it spun relatively freely with seemingly no shaft freeplay.

I have plans to pull the water pump this weekend (car has 122k on it, time for a new timing belt anyway). My concern is with the alternator. I can physically see the water pump pulley slowing down and running irregularly and can feel the grainding, but I couldn't tell with the alternator. Is the alternator also giong bad? Could the excess load from the water pump cause the belt not to drive the alternator enough to charge?

TIA,

JS

Reply to
JS
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The greater the load you place on the alternator, the harder it will be to turn the pulley attached to the alternator. That's why with the belt off (and the engine not running) the alternator pulley spins freely, no load, no pulley resistance. As the load increases, the belt has to work harder to maintain non slippage with the alternator pulley, any slippage and the belt squeals. In one way this is a good sign that the alternator is still working correctly. After you replace the water pump, try roughing up the pulleys with 120 grit sand paper, you've probably polished then quite nicely by now. On the other hand, drawing excessive current from the alternator will cause it to also offer more resistance.

Reply to
Nirodac Yar

From the way you desrcibe things, you have cooked the new set of belts buy having them too loose . Not to be a jerk but if you have to post a question regarding alternator belts, don't think about trying the waterpump. Go here to reserch:

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Reply to
simpleton

If they are not cooked, tighten them again and put a few drops of brake fluid on the inside of the belt. it won't slip, and stops the squeal.

Also check that your crank pulley is not separating into two parts. It's a not uncommon problem, and also causes squeal.

Stewart DIBBS

Reply to
Stewart DIBBS

Thanks to all for the assistance and suggestions.

I'm confident that I can do the water pump and timing belt swap. I've not had really any experience working with imports... most of my experience is teardowns and rebuilds on American iron (Mustangs, Camaros, etc). Not ever having to do a car that didn't have a spring loaded belt tensioner and a serpentine belt system, I erred on the side of caution with the belts, thinking that it would be better to have them loose, slip a little, and tighten them down to have them too tight and kill the bearings ni the water pump. Doing the swap wasn't much of an issue, determining the correct tension was. As it turns out, I guess it didn't matter anyway as it was the water pump giving me problems to begin with. The old belts looked fine - tensioned correctly, not excessively worn. This should have been a flag, but I figured maybe they could use changing anyway.

I'll replace that drive belt, check for crank pulley separation, and clean up the rest of the pulleys with some sandpaper to help grab the belt after doing the water pump.

Thanks again for you help...

JS

.....

Reply to
JS

Mitsu engines are very tight and complex. A f*cking belt problem can really screw over your car -- I learned, from experience. There is a belt (I know not which one) that squeals a bit when I start her up in the morning.

I have been having a good time driving the Jeep/Eagle version of the 1990 Eclipse (TSi, AWD, stick shift) in the bad weather we've been having the past couple of days here in Indy. [Yes, kids, one can do doughnuts on ice/snow in an AWD car...it takes some doing...]

I have determined that Pep Boys' shop a block or two away is not good for more than minor repairs on my 15 year old car. I'm taking her to the Mitsu dealer I trust...lawsuits may follow.

Best regards, Mark "still likes most of the techs he has met at Pep Boys" Gibson

Reply to
Mark Gibson

Your best bet for service on your aging DSM is a box of metric wrenches and

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You guys should consider shelling out for the manual on cd. It has the VFAQ pages, the archives from Todd Day's Talon Digest and the entire service manual for 1.8, 2.0 and 2.0 turbo 1990 through 1999. It will save you money and anguish. Get yours here:

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Reply to
simpleton

For anyone interested....

I picked up my parts this morning and was going to attempt the water pump and timing belt adventure. Remembering Stewart DIBBS' advice, I went for the crank pulley first. I pulled it off, and while inspecting it, noticed that the center of it was moving. It pulled completely out after pushing on it a little.

Time to go to the dealer and get another one.

I'm convinced that this is my problem. After closer inspection, the water pump grinding noise was just the belt laying next to it that I'd thought had fallen. After removing the belts completely, it was quiet. This could also explain the tensioning problem. The belt still looks ok, and the rubberish looking material was probably the center of the crank pulley separating.

I'll do a quick visual check of the timing belt before putting it back together... if it's ok, I'll be putting the belt on when it's warm enough to not have to wear three layers of clothing and stand in front of a turbo heater.

Thanks to everyone for their help, especially Stewart for the heads-up about the pulley separation.

JS

Reply to
JS

"I'll do a quick visual check of the timing belt before putting it back together... if it's ok, I'll be putting the belt on when it's warm enough to not have to wear three layers of clothing and stand in front of a turbo heater."

Man, I know what you're saying here. I once constructed a tent out of plastic tarps and used one of those heaters to survive a January clutch swap in my driveway. You did say though that the car had 122K on it: you "should" be on your third Tbelt. Be careful here....

Reply to
simpleton

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