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93 Geo Metro belt Squeal

06-09-2004, 12:42 PM
I have a 93 Geo Metro. I have replaced the alternator and belt but still receive a squealing sound when the car starts up. The Squeal will go away after the car has ran for a minute but will come back if I turn on too much electrical devices. Is there a censor that can go, making the alternator hard to turn, causing the belt to squeal.

06-09-2004, 03:48 PM
Sounds like it's not tight enough. That, or your alternator bearing is shot.

06-10-2004, 04:59 AM
i would agree with geizukigti. belt may not be tight enough. i have also noticed that metros (specifically 1993 1.0 liter) seem to loose the head gasket on the number one piston corner on the bottom left side. oil and antifreeze will come out but it usually doesnt effect engine performance. fluids will fall straight on to your main pulley. check for that too.

06-10-2004, 06:05 AM
Check any other of the pulleys the belt rides on for looseness. Including the balancer. If all seems OK, the the belt may be loose. If it seems tight, replace the belt with a quality manufacturer like Gates, Dayco or Goodyear even though it was replaced already.

04-13-2009, 11:31 PM
I have the same problem with belt squeal on a 91 Geo Metro. A shop tightened the belt so much I was afraid it would knock out either the water pump or the alternator. All pulleys have been cleaned. I have replaced the belt several times. I have replaced the alternator three times. I have tried three different batteries. I have cleaned all ground connectections under the hood. I even added an extra ground to the alternator. And ran a hot straight to the battery from the alternator. My sqeal happens after start up. Then it stops. Also if the alternator is under a heavy load. ( headlights,brakelights and turn signals all at once.) The alternator was tested off the car and tested good. When they test it they do not put it under a load. This is definitely an electrical problem. Finding the source of the problem is very difficult

04-13-2009, 11:51 PM
The problem may be in the smaller wire that plugs into the voltage regulator in the back of the alternator.

04-14-2009, 07:46 AM
always an interesting question .... since mine has done this for years too. i'm from the older school that suggests it's better to have the belts too loose than wear out the bearings. it's always worth looking for problems or changes but having tried most of the same fixes including 'belt dressing', i'm pretty convinced that the electrical system is doing just exactly what it was designed to do and i'm simply unwilling to tighten the belt enough. i have not broken any belts and when i do replace them occasionally they are less squealy for a while. at 326k it is distracting but everything seems to keep working. i remember it was worst when the main oil seal was weeping but that went away after a timing belt / seal change.

04-14-2009, 08:48 AM
I have a rebuilt engine. There are no oil leaks. I will try cleaning the connecter to the voltage regulator after work today.

04-14-2009, 09:12 AM
I have been fighting the same problem for 100,000 miles on my 93 1.0L. My car destroys a waterpump and two belts every year due to the tightness of the belt needed to stop the squeeling. Right now my pump sounds like a meat grinder.

I have changed EVERY pully, alternator, brackets and tried every belt I could find and they are only a temporary fix. Once it starts squeeling the belt gets glazed and the problem gets worse.

I have wondered about putting a larger pully on the alternator but have not lookrd into the details of such a change.

I have loved my Geo 245,000 miles and still running strong with no engine or tranny work. Even has the original clutch. But this belt problem has been a major PITA!

04-14-2009, 09:49 AM
I have a '93 Metro 3 cyl 5 speed.

I have never had any problem - EXCEPT....

When I run all the electrical crap like Headlights, Heater Fan, Radio, Rear Window Defogger, etc all at once.


If I leave the lights on for even a few minutes after killing the engine.

Also - if your battery is old and won't hold a full charge.

My Metro leaks oil all over the engine and Alternator Belt and still doesn't squeal except as mentioned above.

If it starts squealing after I start the engine, I turn everything off and the squealing stops.

I let the engine run fast for a while to get the Belt to stop squealing and it usually stops squealing permanently.

Do you have a power "Leak" ?....This could be your main problem - disconnect a cable and put an ammeter between
the battery and the cable when the engine is off.
If you see any drain, you have a leak draining your battery.

As someone said, the Metro Alternator and Belt setup are not made to put out a lot of power for dead batteries and accessories.

If your Belt squeals after starting the engine and nothing electrical is turned on, then it is fairly obvious
that you have a bad battery or an electrical drain on the battery and the Alternator is running
under a heavy load charging the Battery.

Also, my water pump has not been changed since I purchased the car maybe 4 years or more ago....

I use the Flat Belt with several ridges running along the length...Schuck's.

If my battery is down at all - I put a battery charger on it overnight so that my Alternator is not taxed.

Perhaps your problem is:

A. Bad Battery
B. Bad Alternator
C. Using excessive (for a Metro) electrical power.
D. Glazed pulleys and/or Alternator Belt.
E. Some drain on the Battery that runs it down when the engine is not running...
D. All of the above together.

The Belt would not be squealing were the Alternator not loaded up.....maybe it is time to install an "ammeter"
to keep track of what is going on....

? ? ? ? ? ? ? ?


"TEA" - Taxed Enough Already !

04-14-2009, 10:48 AM
Glass or sand blasting the alternator pulley will solve your problem. Or a new pulley.

04-14-2009, 01:01 PM

I wish mine was that easy. My battery is new as are ALL of the pulliesand alternator.

We have checked current drain but that is not the problem.

I have used ribbed, flat and every other belt made with same results. I have to get the belt os tight as a banjo string to get it to stop,even right after putting on a new belt. Because it is sooooo tight it destroys water pump bearings on about a year. I have no oil leaks and theengine is spotless.

We have checke pully alignment and still no luck. I like the idea of sandblasting the alternator pully and maybe all the rest to give them more bite.

I guess with 240,000 plus miles on it I should just forget about it as something worse will probaly happen soon.

04-14-2009, 04:06 PM
240,000 miles.

Probably time for a Head rebuild and Rings.....

Does yours get 45 to 50 mpg ?

It will be worth rebuilding !

Gas is already at $2.20 per gallon here in Eastern Washington - probably back to
$3.50 a gallon soon.

If you have an air compressor, buy a sand blasting attachment for $10.

Someone said that toothpaste (the white thick kind) will stop belt squealing.
A blob on each part of the belt between Alternator, Water pump and the main pulley.

? ? ? ?


04-15-2009, 12:57 AM

You might not believe this but at 240,000 miles my Geo runs as good as ever. It starts, idles and runs strong. I average 45 mpg. It has been the best car I ever owned and I bought it new in 93. It really has the original clutch and I see no problems with it.

I often wonder if it lasted so long because I never babied it. I have pushed it hard and for years living in the NC Mountains it was climbing 5000 foot mountains all the time. Maybe that hard use kept the carbon blown out of her. Of course 3000 mile oil/filter changes since new couldn't hurt either.

04-15-2009, 07:38 AM
congrats mowfixer. i have the same good experience with my 91 though i've put in 2 clutches at 326k ..... and now a full rebuild after a blown head gasket and diminishing compression for 50k.

i have not had the water pump and belt change issues though .... just changed the original wp and only 2 belt changes overall. i agree with the 'glazing' analysis as contributing. try roughening of the pulley surface and anything else that does not do too much damage to the original parts. try some 'belt dressing' ... not sure what it's made with. i clean my engine regularly and always finished with armorall for all the rubber and plastic. i wondered if the slippery armorall affected the belt friction for long.

my squeals happened at startup and i always figured it was replacing the energy used to start the engine because it stopped in less than 20-30 seconds or with simple acceleration. i think every system in the metro was designed well for minimum energy cycling and compensation.

04-16-2009, 12:46 AM
I am having a problem with all this...

Why is mine - a normal '93 Metro - not squealing then ?

Normal Alternator and Water Pump. Never changed in about 4 years...

Oil all over everything...messy, but stops the normal Metro rust out death.
Oil on the belt...

Yet you folks are having problems...

What is the difference then ?

Does all this boil down to Pulley Glaze ? The more it squeals, the worse the glaze ?

If you use the Flat Belt with ridges, then deglazing shouldn't be very difficult.

If you have a "V" belt, well.....hmmm? Wire Brush on a drill ?

I'd imagine the direction you rub the glaze off matters - 90 across the Pulley, not along the belt travel direction - which makes it difficult to do.

The Belt will probably be glazed also. Does the Belt Manufacturer matter ?

Any of you who try deglazing, please let us know what happened.

A puzzlement !

DoctorBill over the Hill

Some Web Sites concerning "Deglazing" from a Google Search: read.php%3Fp%3D1372472&ei=6MLmSc6tG5SMtgeQ5rTFBQ&usg=AFQjCNGqZtCjPuxT1_xHWRBbQb6C41hb3g&sig2=wa1wAxx_A5_aY6-pIrxJTw oise.html&ei=6MLmSc6tG5SMtgeQ5rTFBQ&usg=AFQjCNGvq0_ZfFwc33T53mWZud_MNqrIgQ&sig2=h2L0aaTRKBZg62Fuok0KSA

04-16-2009, 04:49 AM
I don't know Doc, I'm in the same boat as you. You need a good belt, Goodyear Gatorback is probably the best. It needs to be very tight, then retightened after 100 miles. Water pumps only last about 90K miles, but then again, so do timing belts, so who cares? Never had any trouble with alternator bearings, my alternators blow a diode around 120K without making a noise.

04-16-2009, 07:23 AM
i don't have the answers but i share similar experience .... and curiosity since i've tried a bunch of fixes unsuccessfully.

drbill, you say you don't have the problem but then you say:


I have never had any problem - EXCEPT....

When I run all the electrical crap like Headlights, Heater Fan, Radio, Rear Window Defogger, etc all at once.


If I leave the lights on for even a few minutes after killing the engine.

Also - if your battery is old and won't hold a full charge.

My Metro leaks oil all over the engine and Alternator Belt and still doesn't squeal except as mentioned above.

If it starts squealing after I start the engine, I turn everything off and the squealing stops.

I let the engine run fast for a while to get the Belt to stop squealing and it usually stops squealing permanently.


.... so evidently yours does sometimes squeal. mine is intermittent too but it sounds like mowfixer and others have a steady problem. all the variables mentioned could contribute i think and he says he's going through water pumps and belts unlike most of the rest of us.

i also noticed that squealing was more consistent in wet weather here in so cal.

04-16-2009, 03:04 PM
Oh yes...I don't have a consistent problem !

Mine will squeal if I run thru a deep puddle and water splashes up into the Belt or if I leave
my parking lights on when I go into a store.

The battery goes down and then on startup the Alternator is heavily tasked and the belt

BUT - If I turn everything off, it usually quiets right down - then a few minutes of charging the battery
all by itself, and I can go.

That is why I asked about a battery drain.

Just a small drain and the Alternator is working hard for maybe a minute.

Heavy fog will condense on the Belt and make it squeal until it dries off.

I think that once a Glaze forms, you are screwed royally.

The WD-40 thing does seem to work in some instances.

I saw somewhere that the Glaze is "water soluble". Strange if true.

I have never tried washing with Windex, or 401, or maybe Comet Powder, or Babo, Kleen King for Stainless Steel would abrade
the Glaze off - acting as an abrasive in water - use with a toothbrush!

Hey - maybe sprinkle some Comet Cleanser, Babo, or "Kleen King" Stainless Steel powdered cleaner
right onto the pulley and let the belt clean the pulley just by spinning...
Then spray some water on it to wash the powder off while the engine idles.
Might work. I'll try almost anything once....except Russian Roulette.

If one could change all the pulleys for twice the width, this problem would disappear, in my Humble Opinion.

The Belt chosen by the designers is a marginal one.

DoctorBill over the Hill

04-16-2009, 10:55 PM
right you are drbill. marginal indeed but optimal for economy.

some thoughts re belts. friction is partly a matter of surface contact area but with the old v belts 'friction' was also increased in the groove by the bending of the flexible belt. the inner part of the v necessarily expanded laterally as the belt wrapped around the sheeve. the expansion locked the belt into the groove. i'm not sure if the same action is at work with the multi groove belts but it should be. once the belt is worn by enough slippage though, the expansion can never be sufficient to lock into the groove .... and the new style belt is limited for the depth that it can be 'adjusted' further down into the groove. the real advantage of the flat, multi groove belts is their flexibility and the consequent reduced power requirements to drive them.

water is the natural lubricant for rubber. anything that holds water to the belt would make it slippery. if wd40 displaces water it might have an advantage. counterintuitive 'slippery logic' but i'll try it sometime.

04-18-2009, 03:58 AM
My 91 3cyl only squeals when it gets a good splash on a rainy day but my 98 4cyl is a pain in the ass. It just gets a little bit worse over time then I have to tighten the crap out of it and it's fine for a few months. Be sure to tighten top and bottom bolts. You can't just get by with the top bolt on these thin belts. You do have to get them VERY tight.:smokin:

05-02-2009, 05:48 PM
I totally agree with Woodie83. A Good Year gatorback belt solved my squealing problem. My car used to squeal very loud after morning startup especially in the winter time, but the squeal would only last about 30 seconds then go away. I replaced the serpentine belt with a good year gatorback belt about a year ago and it hasn't squealed at all since then.

05-03-2009, 08:37 PM
I think you guys are overdoing the tight belt thing. My belts are loose
and they don't squeal. Try loosening.

05-09-2009, 12:31 AM
Have you cleaned and tightened all the electrical wire connections on the alternator? This solved a belt eating problem on another vehicle.

05-27-2009, 11:21 PM
I've had the same problem and what I've found is the rebuilt alternator is the bad guy. On the side of the alternator with 2 legs, one is bolted down solid and the rear (towards the drivers side) has a sliding bushing that is supposed to slip and make contact with the support bracket. Problem is that when this bolt is tightened, the bushing doesn't slip and a bending force is applied to the leg. This contorts the rear frame of the alternator and causes the rear bearing to lock up or drag heavily. This adds to the drag of the alternator and causes belt slip even if the belt is tight. This also causes a noticable whine from the alternator even when the belt isn't slipping and squealing.

Quick fix:
Loosen the lower bolt on the alternator that's toward the drivers side (away from the belt). If all gets better instantly, that's your problem. I used an Autozone rebuild and 2 in a row did the same thing. Get a warranty replacement and make sure that the slip bushing in fact will slip when the bolt/nut is tightened. (a hammer helps) (a knowledgeable rebuilder is better) I intend to be a pest until they get it right.

11-11-2011, 04:17 PM
So I found to day that what is causing my squeal is that the alternator pulley is not properly aligned with the water pump and crankshaft pulleys. It's also causing my car to eat through belts every couple of weeks. So that is also something to check.

11-16-2011, 12:29 AM
I'm like the "doc", My wifes 91 metro has no belt squeal. I just run ordinary NAPA belts 255k miles. 1.0 automatic, 41.5 highway traveling over 5,600 foot pass between Republic & Colville in East. WA.

04-11-2015, 02:42 PM
It is now 2015 Spring ! wow anyway the post by torqued explained the whole issue your belt should have a 1/4" deflection at the widest point if that one bolt as mention on that post by Torqued stated is to tight it won't allow the alternator to line it's self up with the other pulleys think in those terms rather than putting on due load on all your other bearing and bushing by having the belt to tight.

Regards, Paul

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