4.3 Vortec Serpentine Belt Diagram (With And Without AC)

Imagine this: strange, squealing noises are coming from your vehicle’s engine area, and you somehow figure out that it’s due to the damaged serpentine belt.

So, you remove it and get a new belt as a replacement.

But as you stand there, with the new belt in your hands, there’s a problem: you’re not quite sure of the routing path.

Sounds familiar, right?

Well, you’re not alone, as it’s a common issue even among experienced DIY enthusiasts – mainly because each vehicle is different.

To help you out, you’ll discuss serpentine belt diagrams for 4.3 Vortec engines – with and without AC.

4.3 Vortec Serpentine Belt Diagram

This is the standard belt routing diagram for 4.3 Vortec engines.

Put the new serpentine belt around the crankshaft pulley. Then, route it first around the water pump pulley and then around the power steering pump pulley.

After that, route one side of the belt around the AC compressor pulley and the other end around the tensioner and alternator pulley.

As the last step, remove the tension from the tensioner using a ratchet, place the belt under the idler pulley, and re-adjust the tensioner.

For more info, you can watch this video:

4.3 Vortec Serpentine Belt Diagram (No AC)

There are some 4.3 Vortec owners who want to know the belt diagrams for their vehicles that bypass the A/C compressor pulley.

There can be many reasons to do so, but the biggest one is that the A/C compressor pulley in their vehicle is malfunctioning (creating issues for the belt, such as excessive wear or slippage), and they don’t have the budget to have it repaired right now.

So, they try to bypass the A/C compressor pulley from the belt route as a quick fix – until they have the budget to fix the issue.

If you fall into that category, you need to follow this diagram.

As you can see from the above image, the belt will be routed from the power steering pump pulley to the alternator pulley (through the idler pulley), bypassing the AC compressor pulley.

You need to make sure that the belt you’re using is shorter, as it won’t need to loop around the compressor.

4.3 Vortec Belt System Components

So now that we’ve discussed the 4.3 Vortec serpentine belt diagram, with and without AC compressor pulley, it’s time to talk about different components of the vehicle’s belt system.

Serpentine Belt

The main component of the belt system is the serpentine belt itself.

As we’ve discussed above, this belt is routed around several pulleys and drives different accessories connected to the engine.

When the engine is running, the crankshaft rotates, which causes the crankshaft pulley and the serpentine belt to rotate.

Different Pulleys

Once rotating, the serpentine belt starts to drive other pulleys, such as:

Alternator Pulley

The alternator pulley is connected to the alternator.

Therefore, when the pulley starts to rotate, the alternator starts running and powers all electrical systems in your vehicle.

Power Steering Pump Pulley

The power steering pump pulley is connected to the power steering pump, which uses hydraulic pressure to assist in steering the vehicle.

AC Compressor Pulley

The AC compressor pulley is part of the air conditioning system. When the AC is turned on, the clutch in the pulley engages, allowing the belt to drive the compressor.

Idler Pulley

The Idler pully does not drive any accessory but is used to guide the serpentine belt and maintain its path.

Belt Tensioner

Apart from the ones mentioned above, there’s another pulley called the belt tensioner.

Its job is to apply the correct amount of tension to the belt, preventing it from slipping off the pulleys or becoming too tight.

Frequently Asked Questions

What Pulleys Does The Serpentine Belt Go On?

The pulleys a serpentine belt loops around usually include crankshaft pulley, alternator pulley, power steering pump pulley, AC compressor pulley, water pump pulley, tensioner, and idler pulley.

Does Serpentine Belt Direction Matter?

The direction of installation for a new serpentine belt doesn’t matter as it has yet to develop a wear pattern.

In such a situation, you only need to make sure that the grooved side of the belt sits on the pulleys’ grooves.

However, as a serpentine belt gets older, it begins to conform to the shape of the pulleys it runs on.

Therefore, if a used belt is reinstalled in the opposite direction, it may not sit properly on the pulleys, leading to increased wear or noise.

The serpentine belt replacement should take less than one hour if it’s being done by a professional mechanic.

How Much Is The Labor To Put On A Serpentine Belt?

It usually takes $75-$125 to put on a new serpentine belt, depending on your area and the complexity of your vehicle.

Will AutoZone Replace Serpentine Belt?

Yes, AutoZone offers serpentine belt replacement services.

Since the serpentine belt is not directly connected to the internal components of your engine, it will not do any direct damage to it.

However, the engine will overheat if the belt is not working (as it drives the water pump), and this overheating can severely damage the engine.

How Long Do OEM Serpentine Belts Last?

The OEM serpentine belts usually last 50,000-100,00 miles before showing any aging signs.