[JeepsAreBuilt]

I've been working on a project of mine, and I'm swapping in a new radiator, and the lower outlet moved my radiator hose very close to the alternator v-belt, which runs off the crank pulley, around the water pump and alternator. So, I am trying to find a way to improve clearance. One idea that popped up was to install a idler pulley, that would move the v-belt up, but.. I've never seen anything like this. Is this possible ? Can you run a v-belt on its backside over a pulley of some kind ? Or am I dreaming and v-belts really aren't versatile like serpentine belts.

Thanks for any ideas.

[cobalt327]

Originally Posted by JeepsAreBuilt

I've been working on a project of mine, and I'm swapping in a new radiator, and the lower outlet moved my radiator hose very close to the alternator v-belt, which runs off the crank pulley, around the water pump and alternator. So, I am trying to find a way to improve clearance. One idea that popped up was to install a idler pulley, that would move the v-belt up, but.. I've never seen anything like this. Is this possible ? Can you run a v-belt on its backside over a pulley of some kind ? Or am I dreaming and v-belts really aren't versatile like serpentine belts.

Thanks for any ideas.

I would think that the v belt could be tensioned from the smooth side- it might shorten the life somewhat, though.

If the amount of deflection was kept to the minimum needed, and a spare belt was carried... I would try it, if a smaller pulley set wasn't an option.

The belt will bow outward when at speed. Possibly just having the "idler" pulley there in front of the hose, but set to barely touch the belt- or even NOT touch- until the engine was at high enough speed the the belt bowed outward, would be enough to prevent the belt from being able to contact the hose.

[ericnova72]

I have used a round piece of tubing as a "rubbing block" type of stop similar to what Cobalt is suggesting, to prevent belt growth from rubbing on something or climbing out of a pulley, but these didn't run against the belt full time.

Seems like I have seen v-belts with their backs run against idler pulleys, but I can't remember where I have seen it.

[cobalt327]

Originally Posted by ericnova72

Seems like I have seen v-belts with their backs run against idler pulleys, but I can't remember where I have seen it.

Me too- and I just remembered where.

It is on my mower deck! Big-A spring against a smooth, flat pulley that tensions the blade belt. The idler pulley is fairly large diameter, but the amount of deflection is considerable. Never had the blade belt fail, though. Yet... lol

[zbhover]

We use back side idlers to tension the belts on our hovercraft air drives. We are using banded V belts but have never had a problems. Here is a picture of a setup we used on one of them:



On the hovercraft we have now I actually have more deflection in the belt, its about 3 or 4 years old and we've had no problems.

Also I'm an industrial mechanic and while I was going to college for that in the power transmission classes I took I do remember reading that it ok to use a back side idler, but you want to put it on the slack side of the belt. Supposedly it reduces the life of the belt a little but I don't think you'll see a major difference.

I do it all the time and haven't had a problem

Have a good weekend!