Belt Squeak

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imjohnny

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Your A/C unit, not using a 6 rib is still going to throw you're belt in Florida.
That sucker gets very hot running all the time.

Here's one option:
https://www.amazon.com/dp/B01D0L81RE/

CVF Racing... The rest are double or more the price...
I have never used this kit, however look closely when shopping, most DO NOT COME WITH PULLEYS.
They sell separately...

Which side id your A/C on?
Does your a/c bracket have a mount on your exhaust manifold or not?
Lining this stuff up, without buying an engineered kit can get very difficult.
I'm not endorsing this kit either... it was in my research so I had the link for you...
You should contact them with your application and verify it will bolt up at all.
I have thought about the serp conversion so I will look into it. My ac is on the driver side. AC brackets aren't on the exhaust. The front mount is up above the PS and the rear mounts are integrated with the carb mounts. There is absolutely no flex to them.
 

RanchWelder

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Mine is the 77 though, not an 87. No serp belts, no ribbed belts. I have the 3 v belt set up. Can't get rid of ac. I am in Florida and with the kids in the car that is not a recipe for success with no air. Haha. Everything is stock on mine including ac and I am not off roading her. So I think the best option for me is to go with the crank pulley that has all 3 grooves the same height (that is a super easy pulley to get from good manufacturers), and see how it affects the power. Luckily, it is a 77, so there isn't much of power being pulled or needed other than the blower motor and lights at night. If the power isn't what I need, I can always swap to a smaller alternator pulley, or better yet, get mine rebuilt to a higher output and put the smaller pulley on it at the same time.
You may be correct, get the information from March Performance directly.
They will KNOW what pulley you need and what changes to the alternator diameter your adjustment at the crank, will cause you at the alternator.

When I spoke with their engineering dept, I asked them to consider making a low dollar kit for our rigs and they did create one... Do not recall it included A/C because that is where the liability and the extra engineering gets spendy... I completed my mod, before their low dollar system came to market...

They are very easy to deal with. Call them yourself.
 
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RanchWelder

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I have thought about the serp conversion so I will look into it. My ac is on the driver side. AC brackets aren't on the exhaust. The front mount is up above the PS and the rear mounts are integrated with the carb mounts. There is absolutely no flex to them.
My system is only partial serp, and leaves your A/C on a v-belt.
It would upgrade your alt to a better belt.

Send me a picture of your engine with your A/C mod and let me think...
See if you can borrow a set of 87 pulleys so you can see where it improves your system and what the diameter differences are... The smaller alt pulleys are available...

Upgrading the alternator to 6 rib would help you out. the 5/16" belts are bad, unless your running low load/low amp alternator...
 
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fast 99

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Look people this is easy. No need to spend $600. Spent a total of 30 seconds. This may be the correct pully if it was on a long later water pump. Being 2 grove, it probably was. Contact the seller for more information [what it is specifically from] and get a depth measurement. These pulleys aren't rare. There is likely 2-3 at the local pull and save yard.

 
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imjohnny

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Look people this is easy. No need to spend $600. Spent a total of 30 seconds. This may be the correct pully if it was on a long later water pump. Being 2 grove, it probably was. Contact the seller for more information [what it is specifically from] and get a depth measurement. These pulleys aren't rare. There is likely 2-3 at the local pull and save yard.

I can understand that. They aren't rare in the wild in some places. My local yards didn't have them. Can't find them new easily. I am still unsure how it would have 2 different size pulleys going to the same waterpump and not cause an issue. I ended up going to a new pulley that is all the same size. They are all the larger size that used to just go to the alternator. Had to upsize the ac belt a little, but the rest of them worked stock. New harmonic balancer, new front main seal, new crank and water pump pulley, and new belts. Squeak is gone. Runs good. Still has a little bit of a wobble on the crank pulley. Not sure if this is normal. The harmonic balancer is steady and not wobbling at all. Just the pulley. Not as bad as the last one. This is a new pulley too. Here is a video of the wobble:
xc_hide_links_from_guests_guests_error_hide_media

Let me know if that looks normal.
You must be registered for see images attach
 

fast 99

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The 2 different diameters have the same overdrive/underdrive.

As long as you got it fixed to your satisfaction that all that matters.

Reason I got a little short was no reason to spend a bunch of money on a complete drive/bracket/pully system when all you need is one pully.

Doubt the alt will be spinning as fast as before. If battery drain become an issue some other GM brands had very small alt pulleys, such as Olds and Buick. Think they were around 2".

Glad you got it fixed, have fun.
 

imjohnny

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The 2 different diameters have the same overdrive/underdrive.

As long as you got it fixed to your satisfaction that all that matters.

Reason I got a little short was no reason to spend a bunch of money on a complete drive/bracket/pully system when all you need is one pully.

Doubt the alt will be spinning as fast as before. If battery drain become an issue some other GM brands had very small alt pulleys, such as Olds and Buick. Think they were around 2".

Glad you got it fixed, have fun.
I don't think the alt will have a problem. It is on the same size pulley as it was before. It is the same. The other two got bigger instead of making the one smaller. If I do have an issue, I'll be asking for advice on a small pulley alt to grab from the yard. I am glad it is fixed. Just don't want that wobble to be an issue long term.
 

fast 99

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This isn't the first time I have seen the issue you had. May go out and grab a few pulleys just cause.

First thing you may notice on the pulley wobble is belt wear and frequent adjustment.
 

RanchWelder

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Wobble means something is wrong...
The balance matters, buy a good pulley from March...
Junk yard parts could ruin your engine if they are not balanced.
DO NOT RUIN YOUR ENGINE USING **** PARTS.
 
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imjohnny

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Wobble means something is wrong...
The balance matters, buy a good pulley from March...
Junk yard parts could ruin your engine if they are not balanced.
DO NOT RUIN YOUR ENGINE USING **** PARTS.
I didn’t buy from junkyard. Put in a brand new balancer and pulley yesterday. Wobble is still there. Not in the balancer. Just the pulley.
 

RanchWelder

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That sucks... exactly what my statement regarding Dman or used parts...
So many engines get pulled and dropped on the crank and balancer, if the engines was hit in an accident or pulled and dropped on the ground, the bottom pulleys get bent.
The stuff from Dman has been bad, even though it's brand new...
Do you have a bad bearing in you alternator? The shaft play should be minimal...
I have had to throw away an aftermarket alternator which was rebuilt with crap bearings...

My new alt was $360.00 made in USA.

Is there damge to your ring gear or flywheel and did you buy the correct balancer?

My 1987 and 1994 engine's are internally balanced, use a neutral snout balancer and externally balanced on the ring gear...

1986 and earlier, which came with carburators and old pattern head bolts are External ballanced with a different snout balancer... If you look inside the 86 and older balancer's, there's a chunk of steel behind the rubber or steel ring, with the timing marks... If it is not there, you found your issue...

The 87' and newer balancer's will NOT have the steel chunk behind the rubber/steel outer chunk with timing notches.
They will have anywhere from 3-7 drilled 3/8" holes into the rubber/steel, where they were balanced by the manufacturer. Usually behind the back side...
That said, my research on crap aftermarket parts, taught me to by genuine GM Balancer or the $380-$460 race version and nothing in between...

Not one aftermarket balancer company's parts were found within tolerance... at 6K RPM...

This is why you'll find my posts very demanding regarding where you source parts and what you bolt on... Strict

When I asked for a Long Water Pump, and provide a Chevrolet Performance number, so I knew it was correct rotation and the same one installed in the 355HO or Stage 4 and stage 6 TPI GM Performance engines, my local parts store told me off and said, "You'll use what I sell you, off the shelf"...

I tried to pay $150.00 and he insisted I use the cheap $75.00 unit or the $35.00 unit he bought from China aftermarket with substandard bearings... so I had to buy online...

My point is: Every part you select, may cause additional issues...

I have 4 brand new bad from the seller ignition modules...
Bad Lifters, brand new with poor machining, Bad timing set, with sub standard cheapo chain on poor cast iron gears... (from a previously good brand name) Brand new wires, which cause bad timing... (Same store as the pump)...

Pardon me for sounding so pushy, when I make remarks... It's for the best or you'll have a bunch of worthless crap on your shelf as well.

The only thing worse, is somebody learning the hard way what is poor quality, and then find them selling known bad parts to others... so they can get their money back... Ruthless... in my opinion.

Stay alert... add some pics of your balancer... verify your ring gear is not bad / aka missing teeth, cracked or the weight flew off, if you have one... It can happen... and double check your alignment of your belts... Aftermarket ring gears have ruined engines...

You may need a shim somewhere...

If you zoom in on the pictures I showed you, you'll see 1 washer is stacked against the engine spacer at the block and at the alternator bracket pivot... and 2 behind the pivot nut... It must be very well aligned... or you'll eat a belt... vibrate...

The last thing it could be is the centrifugal clutch weights on the A/C or a bad converter bearing / pump bearing at the trans... Bad water pump bearing... bent fan or broken clutch on the fan...

I have seen the fan swapped out and the wrong rotation reverse fan put on the wrong direction assembly as well. The fan will be running backwards if somebody pulled one from a serpentine system. I had a parts store sell me the wrong rotation fan for my serpentine 4.3L...

Same will happen at the water pump... wrong junk yard parts will blow your build. Reverse rotation fan will come through your hood, when it breaks... scare the heck outta yah... NO BS. Could kill someone.

Just keep saying to your self: "Everything Matters, All the Time..."
You'll find it, just hang in there... add some pics...

Do not drive it with a balance issue. You'll break something else...
A worn idler bearing on a serpentine system eats the rear tail shaft bearing at the transmission... believe it or NOT...
 
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Albrigap

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If the PS pump pulley has been removed in the past, make sure it is lined up with the rest of the pulleys or it will wear on one side and chirp. This is especially true with serpentine belts. The pulley is usually flush with the end of the shaft. Dayco makes a laser tool to check this.
 

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If the PS pump pulley has been removed in the past, make sure it is lined up with the rest of the pulleys or it will wear on one side and chirp. This is especially true with serpentine belts. The pulley is usually flush with the end of the shaft. Dayco makes a laser tool to check this.
Use an aluminum yard stick straight edge. HF sells cheap ones that do the job...
You'll need a hand. Most of my alignment was done with the fan removed.
Just nut the water pump pulley on and straight edge away.

When you finally get all the spacing just right and the washers set up perfectly, it's very rewarding. If you have a bad back, you'll want an extra set of hands...

I have encountered bent brackets from previous work, not done by me...
 

Ricko1966

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@RanchWelder I'm so with you on what you were saying about aftermarket parts. It's real hard to convince people that the cheap aftermarket parts aren't the same as OEM parts. Some people think because fits a Chevrolet it's a Chevrolet part.
 
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