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Serpantine belt conversion

twoslo4five0

twoslo4five0

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I have a chance to get a good deal on a complete serp conversion for my TBI 350. I just keep asking myself do I really need this? Other than running one belt what are the advantages of running a serpentine setup? Belt doesn't slip at all? One disadvantage I see it if you break a belt you cant do anything...
 
Do it, it reduces the load on your engine and frees up horsepower.
It gets rid of that little bit of V-belt slip that you don't notice, everything lasts longer because the tension is constant, and it looks better.
 
No squeal, clean, carry 2 extra belts instead of 4. (I say 2 because it's easy to carry 2!)

Also, better alternator choices.
 
It's that little bit of slip that V-belts do even if you don't notice that causes a little jerk jerk jerk on the motor, thus increasing the load as your accessories get pulled back up to speed. And you are powering 1 belt instead of multiple belts.

In reality you probably won't notice a big HP gain, but you might notice it in your MPG.
 
Also there is what's known as friction loss as the thicker v-belt has to wedge into and back out of the pulleys as it goes around. The wide but thin serp belts don't have that issue.

And over all we are talking in the 5-10 hp range so like I said you probably won't notice it on take off, but you might save some gas.

Plus if you throw a belt you don't have to take everything apart, then pry and tighten, you just crank the tensioner over slap on your spare and go.

Others mentioned driving after throwing a v-belt, but what if you break the water pump belt and don't notice? With a serp, when you loose your power steering that is your warning that it's about to overheat.

1 spare under the seat instead of 3 or 4.

I fail to see the down side, other than the kids behind the parts counter that don't know what to do when your answer isn't an option on their computer.
 
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I have heard the HP thing, do I believe it.... meh, maybe. But the convenience of the serp conversion is its huge benefit. Anyone who can honestly come up with a single advantage of a v-belt system over the serp is lost in space. Yes you lose everything when the belt tosses, but honestly how often do you hear of that even happening to begin with? And if that is your main concern, then carry an extra. You only need a 15mm wrench or a prybar to put the belt back on. And serp will never toss the belt unless the belt is bad or a component is bad, which a v-belt will do anyways.
 
I did lose a serpentine belt on a car once because the water pump seized. The car couldn't have been driven if it had V-belts either and it seems to me the water pump is the accessory most likely to lock up.

I like how much easier it is to swap parts with serpentine. You can use alternators and stuff from late 80s to current and all you have to do is mount them. You can also add idlers to either side of the belt to route it wherever you want - even around obstacles that would make V-belt routing impossible. My truck came with triple V-belt and changing out the innermost one was about 1/2-hour, where the serpentine is a couple of minutes. That time applies not only for replacing a belt, but also for working on any of the accessories.
 
I'm not a big fan of serpentine belts,mostly because the idler pulleys often fail with little to no warning and are made of cheap plastic with china ball bearings in them--and you lose ALL accessories when the belt fails or the idler craps out..

But I will admit its nice not having to take off two V belts to replace the innermost one on a v-belt setup (usually the power steering or A/C belt),which can suck if its been a long time since the bolts were last loosened..often there are welded nuts on brackets that bolts like to rust solid into and snap,adding 3 hours to your 15 minute belt replacement job..:mad:...on a truck like mine that has an additional belt in the front to power a plow pump,its an additional hemmeroid to deal with too...

I usually put all new belts on everything and have had good luck not having one fail on the road somewhere ..and at least if one did,I can change it myself...on my Ford Contour,replacing the serp belt involved taking the motor mount off,one of the pulleys,and required a lift and an hour to do it...given the choice I'd rather have to replace a V-belt on my truck...maybe GM trucks are not as bad,I never had to replace one myself,but I did one on a '93 Caravan and it was a job you needed 4 hands to do--two to release the tension on the idler,and two more to put the 90 something inch belt around all the pulleys..I had to get someone to help me...FWD vehickes suck worse,having no good access to the belt and pulleys..
 
I like the serpentine design idea, not sure I like the single belt idea though after running several years with a couple of vehicles running them now.

Not so much of losing a belt issue, my issues have been single accessory problems. Had a couple of alternator issues and power steering pump issues that I most likely could have made it home, if I had the option to remove that single belt.

I kind of like the '87 style of using individual serpentine belts, but sadly they still used a v-belt to run the AC compressor, which I thought was weird, one of the worst belts to slip.
 
Best way is find something in a junkyard or CList. I pulled my stuff from an early 90s V6 1500 truck, even had the needed smog pump for me. They are tricky getting off, you will need deep sockets/ Allen sockets/ and female Torx sockets (reverse of torx wrenches) I used everything but the water pump from that truck (buying a new water pump makes sense) and still using. :waytogo:

I went serp because it's cleaner, holds my Alt and PS pump pulles better, and easier to work on. When you ask more of your Alt and PS pump, you hear the V belt complaining. If it's cold and early, you hear your neighbors complaining.

I have thrown a serpentine belt once, after going through a deep puddle, smog pump ingested water, seized, melted/shredded the belt, and then threw it. Between S10 and K5 serpentine set ups...I have 140k miles of trouble less belt driving. :D
 
I will argue the fact of never throwing the belt. Last year myself and 79pen on here were wheeling at night. He threw the serp. belt many times just trying to get back to camp, overheated, went through a ton of water and PS fluid on the process. Next morning we find out that the brand new PS pulley was wobbiling throwing the serpt belt.

Not saying it was related but his motor didn't live much longer. He could have made it back to camp if it hadn't been for the serpt belt.

He is full hydro without power beyond so there was no way to steer it with the motor off. Took about 5 hours to get back to camp.
 
I don't mean to pick nits but apparently the serpentine belt wasn't the problem, it was the lose power steering pulley.

Most steering control valves will act as a pump to give you at least some control of the steering in the even of belt loss. It's a common safety feature for in case it happens on road.
 
You are correct in the pump was the issue, I was more pointing out a what if this happened sernerio...

Must have some huge muscles to steer a non power beyond valve with 39s off road not under power...
 
Ya, I can't imagine it would be easy, then again I've never had the misfortune of having to try (on a full hydraulic setup) so I don't know. I know I used to drive a 72 international hay truck with a 22' bed, and a working 5th, and it didn't have power steering. The trick is to be rolling or at least rocking while you tug on the wheel. Trying to turn at a dead stop was nearly impossible.

I miss that old truck, that what I learned how to drive in.
 
I did the conversion a few years ago on my old K5. Used the entire setup from a 94 S10 Blazer with a 4.3. Lucked out because it was one without AC so I didn't have to buy a delete pulley. Used the waterpump from that same motor. Upgraded to a higher amp alternator at the same time. The serpentine setup was the only thing I kept from that motor when I parted the truck out.

The only problem I had was when the water pump pulley nuts came off of the front of the water pump and threw off the pulley. Shortly after that the front bearing sheared off of the pump (had some play in it when I re-installed the pulley...which may have been the cause of the nuts loosening). The first time I was lucky and found the pulley and had some nuts in the truck that fit the belt even stayed in the engine compartment. The second time I thought I lost the pulley so I put one on from a different setup I had. I did find it later when the snow melted completely by accident. I was going through the same area on my motorcycle and spotted it out of the corner of my eye.

I carry two spare belts and two spare idler pulleys. Along with the old tensioner from when I replaced it.

I've collected a few complete setups from parting out vehicles. Some off vans, trucks, cars. For the most part, most parts swap between assemblies. You can even mix/match parts. I've got dual alternators because of this.

I say if you are thinking about it, go ahead and do it. But save your old parts for a little while. If you don't like it, swap back and sell the serpentine stuff....someone will want it.

If you do decide to go for it....you don't need to use the studs that the factory did. I use regular bolts. The studs do help with installing the brackets though.
 
currently im running a serp. belt on the alternator, and debateing just adding a serp kit for the power steering or going with a one belt system.
 
Serpentine is the only way to go if you ask me and there are several different factory GM options to choose from. Here is a thread from a few years ago that I contributed several pictures of the various designs used on small blocks and 4.3L’s over the years (there are about 4 different factory serpenite designs for big blocks too) . Some are better than others. My preference is 1996-2000 L31 5.7L brackets mainly because I like the HT6 A/C compressor vs. the R4 that was used on older versions.

Way back in 1996 I swapped my old 350 over to serpentine. I pirated the brackets off of a wrecked brand new truck at the time. There were no forums back then and nobody that know of had done this swap before so I had no idea if it would work or not. In the end it worked great! I did have to drill one hole in the passenger’s side head though. That was the scary part! I reused my p/s pump too and just swapped on a serpentine pulley. If you go with a serp set up I suggest grabbing the fasteners from the donor as well because you will want studs in the block on the main fasteners then use constant prevailing torque nuts to secure brackets. The nice thing about going to serpentine is the fact you can more easily run a higher amperage alternator. I went from a factory 63 AMP alternator to 105 AMP, what was HUGE back in 1996 :haha:

I’ve been running serpentine on this thing now for 18 years on all of the engines that have been in it (350, 454HO, and 8.1L) and have always carried an extra belt, idlers and tensioner. Not once have I needed to replace any of those pieces on the trail but I did have to replace a water pump on my old 454HO on top of Mount Antero which the serpentine brackets sure made for a quick an easy WP swap.

My old serpentine converted 350 with 1995 C/K 4.3/5.0/5.7L brackets. I ran this little contraption from 1996 to 2003 when it got a 454HO, which I ran that engine on L29 7.4L serpentine brackets.

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These brackets used the R4 a/c compressor which is a turd....all 4 of them! :haha:
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These are the best small block brackets in my opinion. 1996-2000 5.0/5.7L. Same brackets used on 4.3L all the way to present day on GM Express and Savanna vans.
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