Here's a serpentine accessory drive installed on our 383ci small-block Chevy. We used new
Car crafting is all about adapting late-model factory pieces to our older muscle cars. The conversion has to be simple, easy to work on, and best of all-inexpensive. Our show car cousins love those all-billet serpentine beltdrive systems because they're so cool looking. But most of us don't have two grand to drop on a pile of billet aluminum parts. However, the idea of a serpentine beltdrive system has serious merit-not the least of which is the simple fact that one belt drives everything. And with a spring-loaded tensioner, you can remove that belt in about three seconds. No more wrestling with multiple adjusters, misaligned slots, and a pile of obscure stamped brackets to retain an alternator and power steering pump on a short water pump V-belt system. There's a much better way.
In the mid-'80s, GM shed its old V-belt accessory drive skin and adopted the much simpler serpentine beltdrive. This system uses a single ribbed belt to drive the water pump, alternator, power steering, and A/C pumps retained by a single spring-loaded tensioner. In older V-belt systems, belt tension was established by leveraging each driven component. The problem with fixed tension is that all rubber drive belts create a standing wave that travels its circumference at a much slower speed than the belt itself. When this standing wave arrives at a fixed pulley, belt tension is reduced and the belt slips. The beauty of a spring-loaded tensioner is that it instantly compensates for this wave, maintaining belt tension. Plus, a standardized belt tension (assuming proper belt length) minimizes the load on the components, improving bearing life.
This is what a stock factory system looks like on our daily driver '93 GMC 5.7L pickup. Al
When these serpentine systems first appeared in the mid-'80s, they were considered expensive and were not immediately embraced by enthusiasts. But now that these systems have been in service for almost 25 years, they are inexpensive and easy to find. The system we decided to adapt is easily found on late '80s through mid-'90s 1/2-ton GM pickup trucks like the C/K1500 as well as on all 4.3L V-6 engines used in S-10 pickups, S-15 Jimmys, and Astro vans. GM built millions of these vehicles, which makes them extremely popular junkyard donors. So if you have a short water pump small-block that throws the belts at the mere suggestion of rpm, follow our lead as we do a little junkyard hunting. The conversion requires a few simple parts that will not only update the charging system but also make your engine easier to service. Check it out.
Here's the drill. We went to the junkyard in search of a typical '80s or '90s serpentine beltdrive system. We know of at least two different drive arrangements, with either the truck system or the same-era Camaro/Firebird TPI accessory drive system. Don't try to mix the parts, as our sources tell us they don't interchange. We decided to go with the C/K1500/S-10 truck system because it is easier to find, which also makes it less expensive. We knew from prior experience that to remove the alternator and power steering pump bracket from the left (driver) side of the engine, we needed a simple power steering pulley puller. This tool is available at almost any auto parts store. We found a Powerbuilt tool (Amazon.com, less than $20.00), but it only removes the pulley. There's also a nice OTC tool for around $35.00 that removes and installs. You will need to press the pulley back on during reassembly. We like the Powerbuilt-style tool because it's shallow and fits in tight spaces.
Removing the serpentine system from the donor vehicle isn't difficult, but remember to get the driver-side alternator/power steering pump bracket, the passenger-side A/C bracket, and all the OE fasteners, as they are a mixed bag of metric and standard thread. Both large brackets bolt to the front of the engine but do not attach directly to the water pump. This is nice because it allows servicing the water pump without removing any brackets. Try that with a V-belt system. We also learned a couple of tricks when removing the cast-aluminum brackets. On the driver side, there's a small fuel line clip that is usually buried in grease and sits over a stud threaded into the block. The bracket won't come off the stud until that clip is removed. On the A/C side, you have to pry the bolts past the compressor to free it before the bracket can be removed. Remember to snag the crank and water pump pulleys along with the power steering pump brace and at least two of the through bolts you'll need for the A/C-delete pulley. We eventually did not reuse the P.S. brace, but that's your call.
If you're really confined by a tight budget, look for a system with fewer miles so you can purchase the alternator and power steering pump along with the brackets and pulleys. We priced all the replacement parts through Rock Auto for our system and learned the most expensive component is the power steering pump-mainly due to its $50.00 core charge. If you can find a used pump in decent condition, you can skip the whole core charge deal that includes the cost of shipping the pump back to Rock Auto.