Idler Pulley On V-belt Set-up

Hi guy, i need some input on Idler Pulley on a V-Belt set-up.

I have issu with slipping belt on the alternator. I did put a high output Cs144 last year and sometime v-belt is slipping.

I started to look over idler pulley, i know these are use almost only on serpentine system but don't know if it's a good thing on a v-belt. I don't want to buy an expensive serpentine system for the amc 360.

I took a picture and draw where i would like to put the idler pulley.

RED Circle is the idler, and yellow line is where the v-belt will pass.

Give me you're impression

 

I am not sure you would be able to get a V belt to ride true from the outside. Seems lk sit could cause premature wear and possible belt derailment. How bout get it tight and spry some belt dressing on it?

 

It's very thight by now, i could give some belt dressing spray a try, but i'm really looking throught this sollution, i read somewhere that waggy had a recall about that problem and they add a idler...

 

Belt dressing just makes a mess either a larger pulley on the alt. To give more purchase (the slight slow down will help as well). Or you have to move the alt. farther away from the water pump to also increase the purchase. The alt. pulley may also be worn and a new one would help.

 

Common Problem with factory belt drive systems , when the folks install high amperage alternators or even more problematic when they install high volume power steering pumps designed for off road use.............both of which can put enormous loads on that little belt which gets hot and slips..................It all boils down to how much contact area can you get the belt to wrap around the pulley?..........most good aftermarket systems are using idlers and try and wrap these driven pulleys about 240 degrees.............much easier with a serpentine system whereby the idler can run on the back side of the belt with no issue...............A larger v-belt and wider groove when running V-belts is the only answer to increase contact area.

 

i like to wrap to pulley more than oem, and that's why i'm looking to a idler pulley , using the
back side of the belt.

As using a wider v belts...it will bring the initial problem, i don't want to put big buck into bigger groove pulley or serpentine system.

 

You're a pretty innovative person. Why not just make a serpentine system of your own? Idler pulleys for that are everywhere. Maybe retrofit an idler pulley from a serpentine system? What I would be worried is how to keep the top part of the belt from riding off the idler and then how to keep the top part of the V belt from scuff off too much of the sides and making the belt narrower, thus making your issues worse over time.

 

Or get the pulleys to run two V-belts. Common on lots of older vehicles to prevent this problem.

 

Finding a pulley for what i'm going to do it's pretty easy, on napa i can buy different size pulley from serpentine system, as for braket it's pretty easy for me to built one.

For the pulley i was planning using a flat one like this picture.



Or i can use a pulley with side, so it will keep the belt over the pulley....



As for the v-belt i could use a serated type belt that will be less stressed with negative wrap....

 

I know....that would be the best sollution, but old cherokee in my area are very rare.....

 

Take a look on ebay and price it out for the double pulleys. As Nickmil says, the double V belt system may be the answer. Might be cheaper too? If I were to do the serpentine system, I would get the spring loaded arm too. Junkyard?

 

So is the picture your motor or not? It looks like it's set up for a dual belt system.

 

not mine, but same as that bt don,t have the set-up for double pulley....

 

My J20 runs dual belts on the air conditioning compressor. I'm sure your alternator is available with a dual pulley. One possibility is to find a set of pulleys for a Wagoneer or J-truck with air conditioning and take over the compressor position for your alternator. You'd have to offset the alternator, but that should be straight forward. Only hangup might be the pulley spacing not being the same for the compressor and the dual-belt alternator. I can measure the pulley spacing and take a picture later, if you are interested.

 

Cs144, 10si and 12si pulley interchange so that's not a worry.

i starter to look on ebay for the right pulley and there is not all of them, just send a email to some guy who fab aluminium pulley....

But Tim, what you opinion about the idler pulley thing?

 

Just my intuition - you need more surface, not more tension. The extra wrap gives you more surface, but not as much as two pulleys would. I would worry that the V-belts are not meant to ride on their back side, that they would deteriorate from being bent backwards and would not be true enough to run smoothly on an idler pulley like that. Don't know - maybe they are ok that way, but I've never seen v-belts used that way.

 

I've been running for two year with my cs144 using only 1 belt and never been a major problem, some squeal sometime but not as much since i change the v-belt two weeks ago. Maybe a bad brand....

 

Interesting question. A larger alternator pulley could help but then you sacrifice the effectiveness of the alternator by reducing it's speed. I believe 2 belts is the better option. As for an idler used with a v-belt we see that regularly with things such as lawnmower decks with v-belt drives. I believe if I were you I would contact a belt manufacture such as Gates and discuss your options. Their website allows to both email a question or use their cyber chat feature to discuss with an engineer.

 

If you do go with a serp system you might want to look into Bulltear.com or for your billet pulleys